CN102017553B - 用于多信道宽带通信系统中的基带预失真线性化的方法和系统 - Google Patents

用于多信道宽带通信系统中的基带预失真线性化的方法和系统 Download PDF

Info

Publication number
CN102017553B
CN102017553B CN200780051434.2A CN200780051434A CN102017553B CN 102017553 B CN102017553 B CN 102017553B CN 200780051434 A CN200780051434 A CN 200780051434A CN 102017553 B CN102017553 B CN 102017553B
Authority
CN
China
Prior art keywords
coefficient
preequalization
centerdot
input signal
communication system
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN200780051434.2A
Other languages
English (en)
Other versions
CN102017553A (zh
Inventor
金钟宪
赵庚浚
金完锺
S·P·斯特普尔顿
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dali Systems Co Ltd
Original Assignee
Dali Systems Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=39563020&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=CN102017553(B) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Dali Systems Co Ltd filed Critical Dali Systems Co Ltd
Publication of CN102017553A publication Critical patent/CN102017553A/zh
Application granted granted Critical
Publication of CN102017553B publication Critical patent/CN102017553B/zh
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03FAMPLIFIERS
    • H03F1/00Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/32Modifications of amplifiers to reduce non-linear distortion
    • H03F1/3241Modifications of amplifiers to reduce non-linear distortion using predistortion circuits
    • H03F1/3247Modifications of amplifiers to reduce non-linear distortion using predistortion circuits using feedback acting on predistortion circuits
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W40/00Communication routing or communication path finding
    • H04W40/02Communication route or path selection, e.g. power-based or shortest path routing
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03FAMPLIFIERS
    • H03F3/00Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/20Power amplifiers, e.g. Class B amplifiers, Class C amplifiers
    • H03F3/24Power amplifiers, e.g. Class B amplifiers, Class C amplifiers of transmitter output stages
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/02Transmitters
    • H04B1/04Circuits
    • H04B1/0475Circuits with means for limiting noise, interference or distortion
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/02Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/022Site diversity; Macro-diversity
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00Baseband systems
    • H04L25/02Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/03Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
    • H04L25/03006Arrangements for removing intersymbol interference
    • H04L25/03343Arrangements at the transmitter end
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00Baseband systems
    • H04L25/38Synchronous or start-stop systems, e.g. for Baudot code
    • H04L25/40Transmitting circuits; Receiving circuits
    • H04L25/49Transmitting circuits; Receiving circuits using code conversion at the transmitter; using predistortion; using insertion of idle bits for obtaining a desired frequency spectrum; using three or more amplitude levels ; Baseband coding techniques specific to data transmission systems
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2614Peak power aspects
    • H04L27/2618Reduction thereof using auxiliary subcarriers
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/32Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
    • H04L27/36Modulator circuits; Transmitter circuits
    • H04L27/362Modulation using more than one carrier, e.g. with quadrature carriers, separately amplitude modulated
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W24/00Supervisory, monitoring or testing arrangements
    • H04W24/02Arrangements for optimising operational condition
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W24/00Supervisory, monitoring or testing arrangements
    • H04W24/04Arrangements for maintaining operational condition
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W40/00Communication routing or communication path finding
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W72/00Local resource management
    • H04W72/04Wireless resource allocation
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W72/00Local resource management
    • H04W72/04Wireless resource allocation
    • H04W72/044Wireless resource allocation based on the type of the allocated resource
    • H04W72/0453Resources in frequency domain, e.g. a carrier in FDMA
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W88/00Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
    • H04W88/08Access point devices
    • H04W88/085Access point devices with remote components
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03FAMPLIFIERS
    • H03F2200/00Indexing scheme relating to amplifiers
    • H03F2200/336A I/Q, i.e. phase quadrature, modulator or demodulator being used in an amplifying circuit
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03FAMPLIFIERS
    • H03F2200/00Indexing scheme relating to amplifiers
    • H03F2200/57Separate feedback of real and complex signals being present
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03FAMPLIFIERS
    • H03F2201/00Indexing scheme relating to details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements covered by H03F1/00
    • H03F2201/32Indexing scheme relating to modifications of amplifiers to reduce non-linear distortion
    • H03F2201/3224Predistortion being done for compensating memory effects
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03FAMPLIFIERS
    • H03F2201/00Indexing scheme relating to details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements covered by H03F1/00
    • H03F2201/32Indexing scheme relating to modifications of amplifiers to reduce non-linear distortion
    • H03F2201/3233Adaptive predistortion using lookup table, e.g. memory, RAM, ROM, LUT, to generate the predistortion
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B1/00Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/02Transmitters
    • H04B1/04Circuits
    • H04B2001/0408Circuits with power amplifiers
    • H04B2001/0425Circuits with power amplifiers with linearisation using predistortion
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00Baseband systems
    • H04L25/02Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/03Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
    • H04L25/03006Arrangements for removing intersymbol interference
    • H04L2025/0335Arrangements for removing intersymbol interference characterised by the type of transmission
    • H04L2025/03375Passband transmission
    • H04L2025/03414Multicarrier

Abstract

公开了一种有效的基带预失真线性化方法,该方法用于在使用有效的多路复用调制技术的宽度通信系统中减少频谱再生并且补偿记忆效应,其中有效的复用调制技术诸如宽度码分多址以及正交频分复用。本发明基于使用分段预均衡的查找表的预失真方法,以利用针对宽度发射器系统的记忆效应补偿来针对所需线性性能降低计算复杂度和数值不稳定性,其中分段预均衡的查找表的预失真是查找表预失真和分段预均衡器的级联。因此,本发明可以在相邻信道功率比方面降低计算负载,这节省了实现中的硬件资源并且改进了性能。

Description

用于多信道宽带通信系统中的基带预失真线性化的方法和系统
相关申请
本申请要求与本申请具有相同发明人的、于2006年12月26日提交的美国临时专利申请S.N.60/877,035的优先权,并且还要求于2007年12月7日提交的美国临时专利申请S.N.61/012416的优先权,通过引用将以上二者合并于此。将美国临时专利申请S.N.61/012,416作为附录1包括进来。
技术领域
本发明一般地涉及使用多路复用调制技术的宽带通信系统。更具体地,本发明涉及用于基带预失真线性化以补偿多信道宽带无线发射器的非线性和记忆效应的方法和系统。
背景技术
由于无线通信系统中频谱效率的重要性增加,射频(RF)功率放大器(PA)的线性和效率对于非恒定包络数字调制方案而言已经成为关键的设计问题,其中非恒定包络数字调制方案具有高的峰值平均功率比(PAR)。RF PA具有非线性,该非线性在PA的输出处产生幅度调制-幅度调制(AM-AM)以及幅度调制-相位调制(AM-PM)失真。这些效应产生了使误差向量幅度(EVM)恶化的相邻信道中的频谱再生和带内失真。
线性和效率之间的关系是一种权衡,因为当放大器在其线性区域中操作时,功率效率非常低,而当驱使放大器进入其压缩区域时,功率效率增大。为了同时增强线性和效率,通常对RF PA应用线性化技术。已经提出了各种线性化技术,诸如反馈、前馈和预失真。
一个技术是基带数字预失真(PD),其通常使用数字信号处理器。与广泛使用的传统的前馈线性化技术相比,数字预失真可以实现改进的线性和改进的功率效率,同时降低了系统复杂度。软件实现为数字预失真器提供了适于多标准环境的重配置性。此外,使用效率增强技术的PA,例如Doherty功率放大器(DPA),能够以线性为代价实现比传统PA设计更高的效率。因此,将数字预失真与使用效率增强技术的PA组合具有改进系统线性和总效率的潜力。
然而,大部分数字PD预设PA没有记忆或具有弱记忆。这在记忆效应使得输出信号是当前以及过去的输入信号的函数的宽带应用中是不切实际的。PA中的记忆效应源包括有源设备的自加热(也称为长时恒定或热记忆效应)以及有源设备的频率依赖性(也称为短时恒定或电子记忆效应),这涉及匹配网络或偏置电路。随着信号带宽增大,PA的记忆效应也变得显著并且限制了无记忆数字PD的性能。
为了克服数字PD中的记忆效应,已经提出了各种方法。对于短期记忆效应,应用Volterra滤波器结构以使用间接学习算法补偿记忆效应,但是优化系数的数量随着阶的增大而非常大。该复杂度使得基于Volterra滤波器的PD在实际的硬件中极难实现。为了减少系数的数量,已经提出了作为Volterra滤波器简化版本的记忆多项式结构,但是就算是该简化版本也仍旧需要大的计算负载。此外,基于记忆多项式的PD在包括高阶多项式项时遭受了数值不稳定性,因为为了估计多项式系数而需要对矩阵取逆。已经利用同样基于正交多项式的复杂结构的备选方案来减轻与传统多项式相关联的数值不稳定性。为了以性能为代价进一步降低复杂度,已经提出了Hammerstein预失真器,其是有限冲激响应(FIR)滤波器或线性时变(LTI)系统,其后跟随有无记忆多项式PD。Hammerstein预失真器假设使用的PA模型遵守是无记忆非线性的Wiener模型结构,其后跟随有有限冲激响应(FIR)滤波器或线性时变(LTI)系统。
该实现意味着Hammerstein结构仅可以补偿来自于RF频率响应的记忆效应。因此,如果RF频率响应非常平坦,则Hammerstein PD不能修正任何其他类型的记忆效应,诸如偏置感应(bias-induced)以及热记忆效应。
最近,使用了与子带滤波块级联的静态查找表(LUT)数字基带PD,这不是为补偿电子记忆效应,而是为了解决由于在针对固定LUTPD进行了初始设置之后,PA的温度改变而引起的增益和相位变化。
因此,在多信道宽带无线发射器中,存在对不仅能够补偿RF频率响应记忆效应而且能够补偿偏置感应或热记忆效应的基带预失真方法的长期需要。
发明内容
因而,本发明基本上克服了现有技术的很多前述限制,并且提供了基带预失真线性化的系统和方法,其补偿了在多信道宽带无线发射器中发现的非线性以及记忆效应。通过使用利用查找表的分段(piecewise)预均衡PD实现了该结果。利用该方法,本发明能够补偿电子以及热记忆效应,而同时与使用记忆多项式PD算法的现有技术系统相比,降低了系统的计算复杂度以及数值不稳定性,同时本发明在得到的多带PA性能中的线性方面可与记忆多项式PD相媲美。
可以从结合附图的以下详细描述中更全面地理解本发明的其他目的和优势,在附图中:
附图说明
图1是示出了根据本发明的分段预均衡LUT预失真系统的示意图。
图2是示出了图1均衡器107的基于多项式的实施方式的示意图。
图3A是示出了复数增益调节器响应的图示。
图3B是示出了根据本发明的分段均衡器响应的图示。
图3C是示出了根据本发明的复数增益调节器和分段均衡器级联的响应的图示。
图3D是示出了功率放大器响应的图示。
图3E是示出了来自于复数增益调节器和分段均衡器级联的响应和复数增益调节器响应的详细响应的图示。
图4A是示出了表示利用使用具有500kHz间隔的八音测试信号的无记忆LUT PD的实施方式进行线性化之前以及之后的线性化结果的图示。
图4B是示出了表示利用使用具有500kHz间隔的八音测试信号的LUT Hammerstein PD进行线性化之前以及之后的线性化结果的图示。
图4C是示出了表示利用使用具有500kHz间隔的八音测试信号的本发明的分段预均衡PD进行线性化之前以及之后的线性化结果的图示。
图4D是示出了表示利用使用具有500kHz间隔的八音测试信号的记忆多项式PD进行线性化之前以及之后的线性化结果的图示。
图5是示出了表示四个类型PD分别使用单个W-CDMA载波的线性化结果的图示,这四种类型的PD包括无记忆LUT PD、LUTHammerstein PD、本发明的分段预均衡PD和记忆多项式PD。
图6是示出了四个类型PD分别使用单个W-CDMA载波的ACPR仿真结果分别性能比较的图示,这四种类型的PD包括无记忆LUTPD、LUT Hammerstein PD、本发明的分段预均衡PD和记忆多项式PD。
图7是示出了四个类型PD分别使用单个W-CDMA载波的测量的线性化结果的图示,这四种类型的PD包括无记忆LUT PD、LUTHammerstein PD、本发明的分段预均衡PD和记忆多项式PD。
图8是示出了四个类型PD分别使用单个W-CDMA载波的ACPR的测量结果的性能比较的图示,这四种类型的PD包括无记忆LUTPD、LUT Hammerstein PD、本发明的分段预均衡PD和记忆多项式PD。
图9是示出了本发明的分段预均衡的PD的复杂度估计的图示。
图10是示出了记忆多项式PD的复杂度估计的图示。
具体实施方式
为了克服在现有技术中发现的记忆多项式PD的计算复杂度和数值不稳定性,因此,本发明利用具有已经被预均衡来补偿记忆效应的LUT的基于LUT的自适应数字预失真系统,从而实现比现有技术更小的计算负载,而同时还将相邻信道功率比(ACPR)降低到基本上与记忆多项式PD已经实现的相同的程度。因此,本发明提供的系统在下文称为分段预均衡的、基于查找表的预失真(PELPD)系统。
现在,将参考附图详细描述根据本发明的PELPD系统的优选和备选实施方式。
图1是示出了根据本发明的PELPD系统的实施方式的示意图。如图所示,用于索引LUT 106的线性幅度寻址(addressing)方法使用如下:
m=round(|u(n)|·N)
其中,u(n)是输入信号101并且所述round函数返回作为索引(m)的最接近整数并且N是LUT 106的大小。
在进行预均衡107之前,将数字复数基带输入信号采样101与从LUT条目中抽取的复数系数102相乘,如下
x(n)=u(n)·Fm(|u(n)|)
其中Fm(|u(n)|)是对应于输入信号101幅度的复数系数102,用于补偿PA 110的AM到AM以及AM到PM失真。
分段预均衡器107的LUT中的N乘K-1个滤波器系数用于补偿记忆效应,其中N是LUT的深度并且FIR滤波器具有K个抽头。在某些实施方式中,由于稳定性问题,分段预均衡器107使用FIR滤波器而不是无限冲激响应(IIR)滤波器,尽管不是所有实施方式都需要FIR滤波器。预均衡器的输出104可以由以下方程描述
z ( n ) = Σ k = 0 K - 1 W k m ( | u ( n ) | ) · x ( n - k )
= Σ k = 0 K - 1 W k m ( | u ( n ) | ) · u ( n - k ) · F m ( | u ( n - k ) | )
其中Wk m(|u(n)|)是对应于所述输入信号u(n)101幅度的第k个抽头的第m个索引的系数。而且,Wk m(|u(n)|)是|u(n)|的函数并且Fm102是|u(n-k)|的函数。出于分析目的,可以由如下多项式模型替代无记忆LUT 106(Fm)结构:
F m ( | u ( n - k ) | ) = Σ p = 1 P b 2 p - 1 · | u ( n - k ) | 2 ( p - 1 )
其中2p-1是多项式阶并且b是对应于该多项式阶的复数系数。此外,注意,抽头系数和无记忆LUT系数(Fm)102分别取决于u(n)和u(n-k)。
因此,可以使用以下多项式方程表示每段均衡器:
z ( n ) = Σ k = 0 K - 1 W k m ( | u ( n ) | ) · Σ p = 1 P b 2 p - 1 · u ( n - k ) · | u ( n - k ) | 2 ( p - 1 )
其中Wk m(|u(n)|)是具有作为|u(n)|函数的第m个索引的第k个抽头系数。不失一般性地,分段预均衡器107可以使用一个I阶多项式进行类似地定义,
z ( n ) = Σ k = 0 K - 1 Σ l = 1 L w k , 2 l - 1 · | u ( n ) | 2 ( l - 1 )
× Σ p = 1 P b 2 p - 1 · u ( n - k ) · | u ( n - k ) | 2 ( p - 1 )
其中Wk,I是第k个抽头的第I阶系数。
在z(n)104的数模转换108之后,该信号上变频109至RF,由生成失真的PA 110放大、衰减113、下变频114至基带并且继而最终进行模数转换115并且应用于延迟116估计算法117。可以由以下方程描述反馈信号y(n-Δ)105,该反馈信号是具有延迟的、PA 110的输出,
y(n-Δ)=G(|z(n-Δ)|)·ej·Φ(|z(n-Δ)|)
其中G(·)和Φ(·)分别是PA 110的AM/AM和AM/PM失真,并且Δ是反馈环路延迟。为了估计Δ,相关技术应用如下:
R ( d ) = 1 N Σ n = 0 N - 1 z ( n ) · y * ( n + d )
其中d是延迟变量并且N是用于进行相关的块大小。
在延迟116估计之后,可以通过以下方程估计无记忆LUT 106系数,该方程是具有间接学习的最小均方(LMS)算法。
Fm(|u(n+1)|)=Fm(|u(n)|)+μ·u(n)·e(n)
其中n是迭代数量,μ是稳定性因子并且e(n)是x(n)-y(n)·Fm(|x(n)|)。
应该指出,已经生成的寻址可以重新用于对y(n)105进行索引,该y(n)105是失真信号,其能够因为不正确的索引而引起另一误差。在该过程期间,将通过分段预均衡器107旁路采样x(n)103。在该间接学习LMS算法收敛之后,激活均衡器107。已经将利用LMS算法的间接学习方法用于对分段滤波器系数进行自适应调整。以向量格式将反馈路径中的多个均衡器107的输入写为
yFI(n)=[yF(n)yF(n-1)…yF(n-K+1)]
其中yF(n)是过去的LUT输出,即,y(n)·Fm(|y(n)|)。
因此,多个FIR滤波器输出yFO(n)可以使用以下方程以向量的格式导出
yFO(n)=Wm·yFI(n)T
W n = W 0 m W 1 m . . . W K - 1 m
其中T是转置算子。
可以如下获得预均衡器107的抽头系数的自适应:
Wm(|u(n+1)|)=Wm(|u(n)|)+μ·(yFI(n)T)*·E(n)
其中E(n)是z(n)和yFO(n)之间的误差信号,并且μ是步长(*表示复数共轭)。自适应算法通过比较反馈信号和输入信号的延迟版本来确定系数值。
参考开始于输出111的反馈路径,应该理解,存在多个备选方案来使用此类反馈以更新LUT值或多项式系数。在某些实施方式中,将PA的输出转换到基带,并且将得到的基带信号与输入信号进行比较。将产生的误差用于修正LUT值和系数。在其他实施方式中,从频谱方面监视来自于PA的输出,并且使用下变频器、带通滤波器和功率检测器监视带外(out of band)失真。然后,将功率检测器值用于调整LUT值或多项式系数。
图2示出了使用多项式方程时分段预均衡器107PD的相应框图。多项式表示需要类似于Volterra系列的太多的复数乘法。如图1所示,当利用基于PELPD的方法时,降低了复杂度,因为所需的计算较少,尽管可能需要更多的存储器。从本文中应该理解,预均衡部分是自适应的并且设计用于修正记忆效应,同时lut主要用于进行预失真以修正在商业PA中发现的其他非线性。
图3A-3D是本发明的PELPD的图示。在图3A中示出了典型的无记忆预失真器响应。图3B示出了划分为N段的分段预失真器产生的滞后。由于功率放大器的滞后不一定均匀分布在整个输入幅度范围上,所以应用分段预均衡器以在整个输入范围获得均匀的补偿。在图3C中示出了本发明的PELPD的输出,其可以被认为源自图3A和图3B的级联。图3D示出了典型的功率放大器响应的响应,并且图3B导致了如图3C所示的本发明的PELPD。图3D示出了具有记忆的典型功率放大器响应的响应。在级联了图3C和图3D之后获得了图3E中希望的线性响应。
为了检验本发明的PELPD的性能,首先执行基于时域测量采样的PA行为建模。该行为模型基于截断的Volterra模型。设计了在最终极处使用两个170W推挽式横向扩散金属氧化物半导体(LDMOS)的300W峰值包络功率(PEP)Doherty PA。该DohertyPA工作于2140MHz频带并且具有61dB的增益,和平均30W输出功率处的28%的功率附加效率(PAE)。为了基于实际PA的测量来构建PA模型,使用测试工作台(test bench)[K.Mekechuk,W.Kim,S.Staleton和J.Kim,“Linearinzing Power Amplifiers Using DigitalPredistortion,EDA Tools and Test hardware”High FrequencyElectronics,pp.18-27,2004年4月]。基于该行为模型,已经仿真了包括无记忆LUT PD、Hammerstein PD、本发明的PELPD和记忆多项式PD的各类PD,并且比较了相邻信道功率比(ACPR)性能。在所有仿真中,将LUT的大小固定为128个条目,这是在考虑量化效应以及存储器大小的情况下的折衷大小。本领域的技术人员应该认识到,针对非线性的补偿量涉及LUT 106的大小。增加LUT大小,虽然产生了更准确的非线性表示,但是在自适应方面付出了更多的代价。因此,LUT大小的选择是准确度和复杂度之间的权衡。
作为测试信号的是单个下行链路W-CDMA载波,其基于第三代合作伙伴计划(3GPP)标准规范的测试模式,具有64个专用物理信道(DPCH),该载波具有3.84Mchips/s和9.8db的波峰因子。首先,将具有9.03db的PAR和4MHz带宽的、具有500kHz间隔的八音信号用于验证所提出的方法,其中该八音信号可与W-CDMA信号相媲美。
图4A-4D是示出了四种类型的PD的线性化之前以及之后的代表性线性化结果的图示。如图4A所示,传统无记忆LUT PD能够改进线性并且还补偿记忆效应。图4B示出了传统的Hammerstein PD,其在10MHz以上使性能恶化,而在10MHz带宽内使其发生改进。如果主信号路径中的RF频率响应非常平坦,则Hammerstein PD不能修正除了频率响应记忆效应之外的任何其他记忆效应。也不存在使用传统Hammerstein PD,对于减小频谱再生而言,也没有显而易见的改进。非常清楚的是:Hammerstein PD对来自于记忆效应的失真进行抑制的能力非常有限。图4C示出了本发明的PELPD(具有2个抽头)的性能。图4D示出了传统记忆多项式PD(具有第5阶和两个记忆项)的性能。通过比较图4A-4D,可以看到,本发明的PELPD在ACPR性能方面可以与记忆多项式PD相媲美。
图5是示出了针对上述四个类型的PD的线性化结果的图示。将单个W-CDMA载波应用于LUT PD、LUT Hammerstein PD、本发明的PELPD以及记忆多项式PD。
图6是示出了分别针对4个类型的ACPR仿真结果的性能比较的图示。与无记忆PD相比,传统Hammerstein PD不能改进来自记忆效应的失真。本发明的PELPD可以抑制归因于非线性和PA记忆效应的失真。
在基于行为PA模型验证了仿真中本发明的PELPD的ACPR性能之后,使用测试工作台中的实际Doherty PA执行实验。发射器原型包括具有两个数模转换器(DAC)和RF上变频器的ESG以及PA。接收器包括RF下变频器、高速模数转换器以及数字下变频器。该接收器原型可以通过VSA构造。对于主DSP,PC用于延迟补偿和预失真算法。作为测试信号,为了验证不同PD的补偿性能,在测量中,将具有3.84Mchips/s和9.8db波峰因子的测试模型1的、具有64DPCH的两个下行链路W-CDMA载波用作输入信号。PD的所有系数通过间接学习算法来标识,该间接学习算法被认为是PA的逆建模。在验证过程期间,使用了256条目LUT、5抽头FIR滤波器的Hammerstein PD、本发明的PELPD(具有2抽头)以及第5阶-2延迟记忆多项式。根据多个测量优化抽头数量的选择。
图7是示出了分别使用单个W-CDMA载波的4类PD在线性化之前和之后的测量的线性化结果的图示。从距中心频率的频率偏移量(5MHz和-5MHz)处执行原型发射器输出处的ACPR计算。
图8是示出了分别使用单个W-CDMA载波的4类PD的ACPR测量结果的性能比较的图示。对于具有带有5抽头滤波器的Hammerstein PD的发射器,ACPR值在上ACPR(5MHz偏移)处比LUT PD大约好1dB,而在下ACPR(-5MHz偏移)处与之相同。本发明的PELPD和第5阶-2记忆多项式PD在ACPR方面显示处接近的补偿性能。对于下ACPR和上ACPR而言,这二者对ACPR的改进比Hammerstein PD和无记忆LUT PD分别好出大约4dB和6dB。
还评估了本发明的PELPD和记忆多项式方法的复杂度(忽略LUT读、写、编索引以及信号幅度的平方根(SQRT)的计算,因为LUT索引不仅取决于方法,还取决于变量,例如幅度、对数、幂等,并且SQRT运算可以以不同的方式实现)。因此,仅通过对每个输入采样的加法(减法)和乘法数量进行计数来评估复杂度。为了考虑实数硬件实现,将复数运算转换为实数运算并且考虑存储器大小。例如,一次复数乘法需要两次实数加法和四次实数乘法。如果N是LUT条目的数量,则所需的存储器大小是2N(I和Q LUT)。
图9是示出了本发明的PELPD的复杂度仿真的图示。如果LUT具有256个条目并且滤波器具有2个抽头,则PD每个采样需要进行40次实数加法(减法)、54次实数乘法以及1542的存储器大小。本发明的PELPD需要与传统Hammerstein PD相同的加法和乘法数量,但是需要更多的存储器。
图10是示出了使用RLS间接学习算法的记忆多项式PD的复杂度估计的图示。在图11中给出了算术运算的数量,其中O等于P(k+1)。例如,P=5并且K=1每个采样需要进行1342次实数加法(减法),1644次实数乘法,以及24的存储器大小。在将乘法数量与本发明的PELPD进行比较时,记忆多项式PD每个采样需要进行多于300次实数乘法。因此,PELPD方法显著降低了复杂度。此外,记忆多项式方法的实数乘法的数量随着多项式阶数和记忆长度的平方指数(square power)增长。
总之,与传统Hammerstein方法比较,本发明的PELPD可以更有效地减小频谱再生并且与记忆多项式PD获得相似的修正能力,但是仅需要更小的复杂度。
尽管已经参考优选和备选实施方式描述了本发明,但是应该理解,本发明不限于所描述的细节。在前面的描述中已经提出了各种变形和修改,并且本领域的技术人员将进行其他变形和修改。因此,旨在将所有此类变形和修改包括在如所附权利要求书所定义的发明范围内。

Claims (10)

1.一种方法,用于减小使用多路复用调制技术的多信道宽带通信系统的相邻信道功率比并且补偿所述多信道宽带通信系统的记忆效应,所述方法包括以下步骤:
根据通信系统的基带输入信号的采样生成地址;
根据所述地址从无记忆查找表中获取条目;以及
将所述基带输入信号和所述查找表条目相乘;以及
对所述相乘步骤进行预均衡,
所述预均衡步骤由以下方程执行:
z ( n ) = Σ k = 0 K - 1 W k m ( | u ( n ) | ) · x ( n - k ) = = Σ k = 0 K - 1 W k m ( | u ( n ) | ) · u ( n - k ) · F m ( | u ( n - k ) | ) ,
其中,是对应于所述输入信号u(n)的幅度的第k个抽头的第m个索引的系数,并且
x(n)=u(n)·Fm(|u(n)|),Fm(|u(n)|)是所述无记忆查找表的复数系数。
2.根据权利要求1所述的方法,其中所述查找表中的所述条目是复数系数。
3.根据权利要求1所述的方法,其中所述预均衡步骤包括分段均衡。
4.根据权利要求1所述的方法,其中所述预均衡步骤使用有限冲激响应滤波。
5.根据权利要求3所述的方法,其中所述分段均衡使用有限冲激响应滤波器,而不是使用无限冲激响应滤波器。
6.根据权利要求1所述的方法,进一步包括使用间接学习方法来更新所述条目。
7.根据权利要求6所述的方法,其中所述间接学习方法使用最小均方算法。
8.根据权利要求1所述的方法,其中通过确定以下方程执行所述获取步骤:
m=round(|u(n)|·N),
其中,u(n)是输入信号,并且所述round函数返回作为索引(m)的最接近整数,并且N是所述查找表的大小。
9.根据权利要求1所述的方法,进一步包括由以下方程获得所述索引的系数的自适应:
wm(|u(n+1)|)=wm(|u(n)|)+μ·(yFI(n)T)*·E(n),
其中yFI(n)是反馈路径中多个均衡器的输入,E(n)是误差信号,μ是步长并且*是复数共轭,并且
10.一种系统,用于减小使用多路复用调制技术的多信道宽带通信系统的相邻信道功率比并且补偿所述多信道宽带通信系统的记忆效应,所述系统包括:
地址生成器,用于根据通信系统的基带输入信号的采样生成地址;
无记忆查找表,其中具有根据所述地址而可寻址的系数;
乘法器,用于组合所述基带输入信号和所述系数即查找表条目;以及
均衡器,用于对乘法器进行预均衡,以补偿所述通信系统的功率放大器中的记忆效应,
所述均衡器通过以下方程执行预均衡:
z ( n ) = Σ k = 0 K - 1 W k m ( | u ( n ) | ) · x ( n - k ) = = Σ k = 0 K - 1 W k m ( | u ( n ) | ) · u ( n - k ) · F m ( | u ( n - k ) | ) ,
其中,是对应于所述输入信号u(n)的幅度的第k个抽头的第m个索引的系数,并且
x(n)=u(n)·Fm(|u(n)|),Fm(|u(n)|)是所述无记忆查找表的复数系数。
CN200780051434.2A 2006-12-26 2007-12-20 用于多信道宽带通信系统中的基带预失真线性化的方法和系统 Active CN102017553B (zh)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US87703506P 2006-12-26 2006-12-26
US60/877,035 2006-12-26
US1241607P 2007-12-07 2007-12-07
US61/012,416 2007-12-07
PCT/IB2007/004404 WO2008078195A2 (en) 2006-12-26 2007-12-20 Method and system for baseband predistortion linearization in multi-channel wideband communication systems

Related Child Applications (1)

Application Number Title Priority Date Filing Date
CN201410462933.2A Division CN104202279A (zh) 2006-12-26 2007-12-20 用于多信道宽带通信系统中的基带预失真线性化的方法和系统

Publications (2)

Publication Number Publication Date
CN102017553A CN102017553A (zh) 2011-04-13
CN102017553B true CN102017553B (zh) 2014-10-15

Family

ID=39563020

Family Applications (2)

Application Number Title Priority Date Filing Date
CN200780051434.2A Active CN102017553B (zh) 2006-12-26 2007-12-20 用于多信道宽带通信系统中的基带预失真线性化的方法和系统
CN201410462933.2A Pending CN104202279A (zh) 2006-12-26 2007-12-20 用于多信道宽带通信系统中的基带预失真线性化的方法和系统

Family Applications After (1)

Application Number Title Priority Date Filing Date
CN201410462933.2A Pending CN104202279A (zh) 2006-12-26 2007-12-20 用于多信道宽带通信系统中的基带预失真线性化的方法和系统

Country Status (7)

Country Link
US (17) US8149950B2 (zh)
EP (3) EP3790244A1 (zh)
JP (1) JP5236661B2 (zh)
KR (2) KR20100014339A (zh)
CN (2) CN102017553B (zh)
HK (1) HK1205382A1 (zh)
WO (1) WO2008078195A2 (zh)

Families Citing this family (211)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8811917B2 (en) 2002-05-01 2014-08-19 Dali Systems Co. Ltd. Digital hybrid mode power amplifier system
US8380143B2 (en) 2002-05-01 2013-02-19 Dali Systems Co. Ltd Power amplifier time-delay invariant predistortion methods and apparatus
US7796960B1 (en) * 2006-04-04 2010-09-14 Nortel Networks Limited Signal transmitter linearization
US8886341B1 (en) 2006-04-04 2014-11-11 Microsoft Corporation Adaptive sample-by-sample controller for under-determined systems
CA2637228C (en) * 2006-04-10 2014-04-08 Telefonaktiebolaget L M Ericsson (Publ) A method and apparatus for reducing frequency memory effects in rf power amplifiers
US9026067B2 (en) * 2007-04-23 2015-05-05 Dali Systems Co. Ltd. Remotely reconfigurable power amplifier system and method
CN102017553B (zh) 2006-12-26 2014-10-15 大力系统有限公司 用于多信道宽带通信系统中的基带预失真线性化的方法和系统
EP2203799A4 (en) 2007-10-22 2017-05-17 Mobileaccess Networks Ltd. Communication system using low bandwidth wires
JP2009111958A (ja) * 2007-11-01 2009-05-21 Hitachi Kokusai Electric Inc プリディストータ
EP2248255A4 (en) 2007-12-07 2014-05-28 Dali Systems Co Ltd DIGITAL PREDISTORSION RF DERIVED BASEBAND
JP4996502B2 (ja) * 2008-02-20 2012-08-08 日本無線株式会社 歪補償回路及びプリディストーション型歪補償増幅器
US8064851B2 (en) * 2008-03-06 2011-11-22 Crestcom, Inc. RF transmitter with bias-signal-induced distortion compensation and method therefor
JP5115979B2 (ja) * 2008-07-24 2013-01-09 日本無線株式会社 プリディストータ
JP5205182B2 (ja) * 2008-09-09 2013-06-05 株式会社日立国際電気 歪補償増幅装置
TWI390839B (zh) * 2008-11-17 2013-03-21 Realtek Semiconductor Corp 功率放大器的失真校正裝置與方法
JP5238461B2 (ja) * 2008-11-19 2013-07-17 日本無線株式会社 プリディストータ
CN102396171B (zh) 2009-02-03 2015-09-30 康宁光缆系统有限责任公司 基于光纤的分布式天线系统、组件和用于监视和配置基于光纤的分布式天线系统、组件的相关方法
EP2430531B1 (en) * 2009-04-24 2019-12-04 Dali Systems Co. Ltd. Remotely reconfigurable power amplifier system and method
US8837629B2 (en) * 2011-05-11 2014-09-16 Fadhel M Ghannouchi Extended bandwidth digital Doherty transmitter
CA2704522C (en) 2009-05-14 2017-02-14 Seyed Aidin Bassam Multi-cell processing architectures for modeling and impairment compensation in multi-input multi-output systems
KR101348275B1 (ko) * 2009-09-17 2014-01-08 한국전자통신연구원 전력 증폭기의 전치 왜곡 장치와 방법
CN102025327B (zh) * 2009-09-18 2013-01-02 富士通株式会社 放大器装置和预失真控制方法
JP5339083B2 (ja) * 2009-10-06 2013-11-13 日本電気株式会社 ディジタル歪補償方法及び回路
US8280259B2 (en) 2009-11-13 2012-10-02 Corning Cable Systems Llc Radio-over-fiber (RoF) system for protocol-independent wired and/or wireless communication
US8804870B2 (en) 2009-12-21 2014-08-12 Dali Systems Co. Ltd. Modulation agnostic digital hybrid mode power amplifier system and method
US8542768B2 (en) 2009-12-21 2013-09-24 Dali Systems Co. Ltd. High efficiency, remotely reconfigurable remote radio head unit system and method for wireless communications
FR2954624B1 (fr) 2009-12-23 2012-09-07 Thales Sa Dispositif de linearisation pour amplificateur de puissance.
CN102130697B (zh) 2010-01-20 2015-05-27 华为技术有限公司 接收机、发射机及反馈装置、收发信机和信号处理方法
US8275265B2 (en) 2010-02-15 2012-09-25 Corning Cable Systems Llc Dynamic cell bonding (DCB) for radio-over-fiber (RoF)-based networks and communication systems and related methods
US8792581B2 (en) * 2010-02-18 2014-07-29 Telefonaktiebolaget Lm Ericsson (Publ) RF clock generator with spurious tone cancellation
EP2815502B1 (en) 2010-04-21 2018-03-14 ZTE Corporation Improved capture buffer of digital predistortion systems
US9525488B2 (en) 2010-05-02 2016-12-20 Corning Optical Communications LLC Digital data services and/or power distribution in optical fiber-based distributed communications systems providing digital data and radio frequency (RF) communications services, and related components and methods
CN103119865A (zh) 2010-08-16 2013-05-22 康宁光缆系统有限责任公司 支持远程天线单元之间的数字数据信号传播的远程天线集群和相关系统、组件和方法
KR20180026793A (ko) 2010-08-17 2018-03-13 달리 시스템즈 씨오. 엘티디. 분산 안테나 시스템을 위한 뉴트럴 호스트 아키텍처
KR101829517B1 (ko) 2010-09-14 2018-02-14 달리 시스템즈 씨오. 엘티디. 원격으로 재구성가능한 분산 안테나 시스템 및 방법
JP2012065154A (ja) * 2010-09-16 2012-03-29 Toshiba Corp 歪み補償の装置および方法
US9252874B2 (en) 2010-10-13 2016-02-02 Ccs Technology, Inc Power management for remote antenna units in distributed antenna systems
DE102010064396A1 (de) * 2010-12-30 2012-07-05 Intel Mobile Communications GmbH HF-Rückkopplungsempfängeranordnung, HF-Sendeanordnung und HF-Sende-Empfangsanordnung
JP5707999B2 (ja) * 2011-02-09 2015-04-30 富士通株式会社 歪補償装置、送信機及び歪補償方法
CN203504582U (zh) 2011-02-21 2014-03-26 康宁光缆系统有限责任公司 一种分布式天线系统及用于在其中分配电力的电源装置
CN102651725B (zh) * 2011-02-25 2015-01-28 中兴通讯股份有限公司 一种多用户频偏补偿方法及装置
US9680567B2 (en) * 2011-03-03 2017-06-13 Acacia Communications, Inc. Fault localization and fiber security in optical transponders
TWI556597B (zh) * 2011-03-31 2016-11-01 Panasonic Corp Wireless communication device
WO2012148940A1 (en) 2011-04-29 2012-11-01 Corning Cable Systems Llc Systems, methods, and devices for increasing radio frequency (rf) power in distributed antenna systems
EP2719138B1 (en) 2011-06-09 2020-05-20 CommScope Technologies LLC Distributed antenna system interface for processing digital signals in a standardized format
EP2732653B1 (en) 2011-07-11 2019-10-09 CommScope Technologies LLC Method and apparatuses for managing a distributed antenna system
CN102354118B (zh) * 2011-08-10 2013-10-16 复旦大学 一种适于硬件实现的数字预失真算法系统
CN103875270B (zh) 2011-08-29 2018-01-05 康普技术有限责任公司 配置分布式天线系统
WO2013033715A2 (en) 2011-09-02 2013-03-07 Dali Systems Co. Ltd. Software configurable distributed antenna system and method for reducing uplink noise
JP6080854B2 (ja) 2011-09-22 2017-02-15 ダリ システムズ カンパニー リミテッド マルチチャネル広帯域通信システムにおいてデジタルプリディストーションの帯域幅を増大するシステム及び方法
US8817859B2 (en) * 2011-10-14 2014-08-26 Fadhel Ghannouchi Digital multi-band predistortion linearizer with nonlinear subsampling algorithm in the feedback loop
US8884796B2 (en) * 2011-10-20 2014-11-11 Kathrein-Werke Kg Delta-sigma modulator with feedback signal modification
IN2014CN04237A (zh) 2011-11-07 2015-07-17 Dali Systems Co Ltd
US9420628B2 (en) * 2011-11-07 2016-08-16 Dali Systems Co. Ltd. Virtualized wireless network with pilot beacons
MY172058A (en) 2011-11-07 2019-11-13 Dali Systems Co Ltd Virtualized wireless network
JP5710026B2 (ja) * 2011-12-26 2015-04-30 三菱電機株式会社 アナログフィードバック増幅器
US9148839B2 (en) * 2012-02-17 2015-09-29 Dali Systems Co. Ltd. Evolutionary algorithms for geographic load balancing using a distributed antenna system
US8798559B2 (en) * 2012-02-28 2014-08-05 Telefonaktiebolaget L M Ericsson (Publ) FIR/IIR filter predistorter for power amplifiers exhibiting short-term and/or long-term memory effects
EP2829152A2 (en) 2012-03-23 2015-01-28 Corning Optical Communications Wireless Ltd. Radio-frequency integrated circuit (rfic) chip(s) for providing distributed antenna system functionalities, and related components, systems, and methods
WO2013148986A1 (en) 2012-03-30 2013-10-03 Corning Cable Systems Llc Reducing location-dependent interference in distributed antenna systems operating in multiple-input, multiple-output (mimo) configuration, and related components, systems, and methods
TWI481219B (zh) * 2012-04-13 2015-04-11 Accton Technology Corp 無線中繼站之施體天線裝置、服務天線裝置及其訊號傳輸方法
EP2667507B1 (en) * 2012-05-21 2014-10-29 Alcatel Lucent Amplifier
US9363768B2 (en) * 2012-07-09 2016-06-07 Dali Systems Co. Ltd. Self-optimizing distributed antenna system using soft frequency reuse
US9107086B2 (en) 2012-07-20 2015-08-11 Adc Telecommunications, Inc. Integration panel
US10506454B2 (en) * 2012-07-31 2019-12-10 Dali Systems Co., Ltd. Optimization of traffic load in a distributed antenna system
EP2789107B1 (en) 2012-08-09 2017-02-15 Axell Wireless Ltd. A digital capacity centric distributed antenna system
US9439242B2 (en) 2012-08-13 2016-09-06 Dali Systems Co., Ltd. Time synchronized routing in a distributed antenna system
JP5853913B2 (ja) * 2012-09-12 2016-02-09 富士通株式会社 アドレス制御装置、送信装置およびアドレス制御方法
US8913689B2 (en) 2012-09-24 2014-12-16 Dali Systems Co. Ltd. Wide bandwidth digital predistortion system with reduced sampling rate
WO2014053149A1 (en) 2012-10-05 2014-04-10 Andrew Wireless Systems Gmbh Capacity optimization sub-system for distributed antenna system
US9112549B2 (en) * 2012-10-05 2015-08-18 Dali Systems Co. Ltd. DAS integrated digital off-air repeater
EP3285446B1 (en) * 2012-10-31 2020-10-14 CommScope Technologies LLC Digital baseband transport in telecommunications distribution systems
US9455784B2 (en) 2012-10-31 2016-09-27 Corning Optical Communications Wireless Ltd Deployable wireless infrastructures and methods of deploying wireless infrastructures
EP2923475B1 (en) 2012-11-26 2018-02-14 ADC Telecommunications, Inc. Flexible, reconfigurable multipoint-to-multipoint digital radio frequency transport architecture
KR102306625B1 (ko) 2012-11-26 2021-09-28 콤스코프 테크놀로지스 엘엘씨 디지털 라디오 주파수 전송 아키텍쳐를 위한 타임슬롯 매핑 및/또는 어그리게이션 엘리먼트
EP2923473B1 (en) 2012-11-26 2017-08-09 ADC Telecommunications, Inc. Forward-path digital summation in digital radio frequency transport
JP6002557B2 (ja) * 2012-11-28 2016-10-05 株式会社日立製作所 光多値信号予等化回路、光多値信号予等化送信器及び偏波多重光予等化送信器
WO2014085115A1 (en) 2012-11-29 2014-06-05 Corning Cable Systems Llc HYBRID INTRA-CELL / INTER-CELL REMOTE UNIT ANTENNA BONDING IN MULTIPLE-INPUT, MULTIPLE-OUTPUT (MIMO) DISTRIBUTED ANTENNA SYSTEMS (DASs)
ITMO20120317A1 (it) * 2012-12-21 2014-06-22 Teko Telecom S P A Sistema e metodo per la predistorsione digitale in amplificatori di potenza, particolarmente per comunicazioni a radiofrequenza
JP6054739B2 (ja) * 2012-12-26 2016-12-27 パナソニック株式会社 歪み補償装置及び歪み補償方法
CN103051574B (zh) * 2013-01-16 2016-05-11 大唐移动通信设备有限公司 数字预失真处理方法及系统
US20140320340A1 (en) * 2013-02-21 2014-10-30 Dali Systems Co. Ltd. Indoor localization using analog off-air access units
KR102058437B1 (ko) 2013-02-25 2019-12-26 삼성전자주식회사 필터 값 추출기를 포함하는 터치 감지 장치 및 필터 값 추출기
US9955361B2 (en) 2013-02-26 2018-04-24 Dali Systems Co., Ltd. Method and system for WI-FI data transmission
US8989307B2 (en) * 2013-03-05 2015-03-24 Qualcomm Incorporated Power amplifier system including a composite digital predistorter
US9680423B2 (en) * 2013-03-13 2017-06-13 Analog Devices Global Under-sampling digital pre-distortion architecture
US9851445B2 (en) * 2013-04-23 2017-12-26 Dali Systems Co. Ltd. Real-time locating system using GPS time difference of arrival with digital off-air access units and remote units
US9172334B2 (en) * 2013-05-09 2015-10-27 King Fahd University Of Petroleum And Minerals Digital predistortion system and method with extended correction bandwidth
US20140333376A1 (en) * 2013-05-09 2014-11-13 King Fahd University Of Petroleum And Minerals Scalable digital predistortion system
WO2014184774A1 (en) * 2013-05-16 2014-11-20 Telefonaktiebolaget L M Ericsson (Publ) Baseband equivalent volterra series for digital predistortion in multi-band power amplifiers
EP3000175B1 (en) 2013-05-20 2019-02-27 Analog Devices, Inc. Relaxed digitization system linearization
US9385762B2 (en) 2013-05-22 2016-07-05 Telefonaktiebolaget L M Ericsson (Publ) Linearization of intermodulation bands for concurrent dual-band power amplifiers
US9252718B2 (en) 2013-05-22 2016-02-02 Telefonaktiebolaget L M Ericsson (Publ) Low complexity digital predistortion for concurrent multi-band transmitters
CN103401511A (zh) * 2013-07-05 2013-11-20 华南理工大学 一种用于实时性系统的功放预失真方法
ES2875954T3 (es) 2013-07-11 2021-11-11 Andrew Wireless Systems Gmbh Arquitectura de red celular pequeña para el servicio de múltiples operadores de red
US9750082B2 (en) 2013-10-07 2017-08-29 Commscope Technologies Llc Systems and methods for noise floor optimization in distributed antenna system with direct digital interface to base station
US9787457B2 (en) 2013-10-07 2017-10-10 Commscope Technologies Llc Systems and methods for integrating asynchronous signals in distributed antenna system with direct digital interface to base station
JP6255917B2 (ja) * 2013-11-07 2018-01-10 富士通株式会社 無線装置及び無線アクセスシステム
KR102189745B1 (ko) * 2013-12-06 2020-12-14 주식회사 쏠리드 광 중계 시스템의 리모트 장치
US9847816B2 (en) * 2013-12-19 2017-12-19 Dali Systems Co. Ltd. Digital transport of data over distributed antenna network
US20170250927A1 (en) 2013-12-23 2017-08-31 Dali Systems Co. Ltd. Virtual radio access network using software-defined network of remotes and digital multiplexing switches
EP3092832A4 (en) * 2014-01-06 2017-08-23 Dali Systems Co. Ltd. Network switch for a distributed antenna network
CN104796364B (zh) * 2014-01-16 2018-02-27 京信通信系统(中国)有限公司 一种预失真参数求取方法及预失真处理系统
US10284296B2 (en) * 2014-02-13 2019-05-07 Dali Systems Co. Ltd. System and method for performance optimization in and through a distributed antenna system
EP3108627A4 (en) * 2014-02-18 2017-10-11 CommScope Technologies LLC Selectively combining uplink signals in distributed antenna systems
EP3843296A1 (en) * 2014-02-21 2021-06-30 CommScope Technologies LLC A self-optimizing network entity for a telecommunications system
US9775123B2 (en) 2014-03-28 2017-09-26 Corning Optical Communications Wireless Ltd. Individualized gain control of uplink paths in remote units in a distributed antenna system (DAS) based on individual remote unit contribution to combined uplink power
WO2015151086A1 (en) * 2014-03-31 2015-10-08 Corning Optical Communications Wireless Ltd. Distributed antenna system continuity
EP4024719A1 (en) 2014-04-15 2022-07-06 CommScope Technologies LLC Wideband remote unit for distributed antenna system
WO2015163800A1 (en) * 2014-04-24 2015-10-29 Telefonaktiebolaget L M Ericsson (Publ) Compensation for non-linearity in a radio frequency power amplifier
US9408092B2 (en) * 2014-05-23 2016-08-02 Verizon Patent And Licensing Inc. RAN performance through digital signal processing between baseband unit and remote radio heads
US9252821B2 (en) 2014-06-27 2016-02-02 Freescale Semiconductor, Inc. Adaptive high-order nonlinear function approximation using time-domain volterra series to provide flexible high performance digital pre-distortion
US9628119B2 (en) 2014-06-27 2017-04-18 Nxp Usa, Inc. Adaptive high-order nonlinear function approximation using time-domain volterra series to provide flexible high performance digital pre-distortion
US9525472B2 (en) 2014-07-30 2016-12-20 Corning Incorporated Reducing location-dependent destructive interference in distributed antenna systems (DASS) operating in multiple-input, multiple-output (MIMO) configuration, and related components, systems, and methods
US9730228B2 (en) 2014-08-29 2017-08-08 Corning Optical Communications Wireless Ltd Individualized gain control of remote uplink band paths in a remote unit in a distributed antenna system (DAS), based on combined uplink power level in the remote unit
US10396917B2 (en) 2014-09-23 2019-08-27 Axell Wireless Ltd. Automatic mapping and handling PIM and other uplink interferences in digital distributed antenna systems
US9420542B2 (en) 2014-09-25 2016-08-16 Corning Optical Communications Wireless Ltd System-wide uplink band gain control in a distributed antenna system (DAS), based on per band gain control of remote uplink paths in remote units
US10659163B2 (en) 2014-09-25 2020-05-19 Corning Optical Communications LLC Supporting analog remote antenna units (RAUs) in digital distributed antenna systems (DASs) using analog RAU digital adaptors
US9184960B1 (en) 2014-09-25 2015-11-10 Corning Optical Communications Wireless Ltd Frequency shifting a communications signal(s) in a multi-frequency distributed antenna system (DAS) to avoid or reduce frequency interference
JP2016072696A (ja) 2014-09-26 2016-05-09 富士通株式会社 歪み補償装置及び歪み補償方法
WO2016071902A1 (en) 2014-11-03 2016-05-12 Corning Optical Communications Wireless Ltd. Multi-band monopole planar antennas configured to facilitate improved radio frequency (rf) isolation in multiple-input multiple-output (mimo) antenna arrangement
WO2016075696A1 (en) 2014-11-13 2016-05-19 Corning Optical Communications Wireless Ltd. Analog distributed antenna systems (dass) supporting distribution of digital communications signals interfaced from a digital signal source and analog radio frequency (rf) communications signals
US9729267B2 (en) 2014-12-11 2017-08-08 Corning Optical Communications Wireless Ltd Multiplexing two separate optical links with the same wavelength using asymmetric combining and splitting
WO2016098109A1 (en) 2014-12-18 2016-06-23 Corning Optical Communications Wireless Ltd. Digital interface modules (dims) for flexibly distributing digital and/or analog communications signals in wide-area analog distributed antenna systems (dass)
WO2016098111A1 (en) 2014-12-18 2016-06-23 Corning Optical Communications Wireless Ltd. Digital- analog interface modules (da!ms) for flexibly.distributing digital and/or analog communications signals in wide-area analog distributed antenna systems (dass)
EP3238352A4 (en) 2014-12-23 2018-08-22 Axell Wireless Ltd. Harmonizing noise aggregation and noise management in distributed antenna system
US9362942B1 (en) * 2015-01-12 2016-06-07 Maxim Integrated Products, Inc. System characteristic identification systems and methods
KR102299089B1 (ko) * 2015-02-02 2021-09-07 삼성전자 주식회사 무선 통신 시스템에서 무선 주파수 유닛의 입출력 신호 동기화 방법 및 장치
EP3254421B1 (en) 2015-02-05 2022-05-04 Commscope Technologies LLC Systems and methods for emulating uplink diversity signals
EP3269118B8 (en) 2015-03-11 2021-03-17 CommScope, Inc. of North Carolina Distributed radio access network with adaptive fronthaul
US9980318B2 (en) 2015-03-16 2018-05-22 Commscope Technologies Llc DAS management by radio access network node
CN104796091B (zh) * 2015-04-13 2017-12-12 南京理工大学 基于分段记忆多项式的功率放大器建模及数字预失真方法
US9484962B1 (en) * 2015-06-05 2016-11-01 Infineon Technologies Ag Device and method for adaptive digital pre-distortion
US9712343B2 (en) 2015-06-19 2017-07-18 Andrew Wireless Systems Gmbh Scalable telecommunications system
CN105024960B (zh) * 2015-06-23 2018-11-09 大唐移动通信设备有限公司 一种dpd系统
CN114710122A (zh) * 2015-08-14 2022-07-05 维尔塞特公司 数字动态偏置电路
CN106507462B (zh) * 2015-09-07 2019-11-29 大唐移动通信设备有限公司 一种射频拉远单元rru下行功率的检测方法和装置
WO2017054149A1 (zh) * 2015-09-30 2017-04-06 华为技术有限公司 传输信号的装置和方法
WO2017070635A1 (en) 2015-10-22 2017-04-27 Phluido, Inc. Virtualization and orchestration of a radio access network
CN105305979B (zh) * 2015-11-03 2018-03-06 南京邮电大学 一种改善线性度的分布式放大器电路
CN105356855B (zh) * 2015-11-03 2018-03-13 南京邮电大学 一种可调的分布式放大器电路
US9590668B1 (en) 2015-11-30 2017-03-07 NanoSemi Technologies Digital compensator
CN105631540A (zh) * 2015-12-27 2016-06-01 哈尔滨米米米业科技有限公司 一种基于和声搜索算法的水下潜器路径规划系统
US10638326B2 (en) 2016-02-19 2020-04-28 Corning Optical Communications LLC Long term evolution (LTE) system operating in an unlicensed spectral band with active network discovery and optimization of the unlicensed channels
KR101791636B1 (ko) * 2016-03-28 2017-10-30 주식회사 쏠리드 기지국 신호 정합 장치, 이를 포함하는 기지국 인터페이스 유닛 및 분산 안테나 시스템
US10236924B2 (en) * 2016-03-31 2019-03-19 Corning Optical Communications Wireless Ltd Reducing out-of-channel noise in a wireless distribution system (WDS)
US10644798B2 (en) 2016-05-12 2020-05-05 Dali Systems Co. Ltd. Redundancy in a public safety Distributed Antenna System
US10164675B2 (en) 2016-05-27 2018-12-25 Corning Incorporated Wideband digital distributed communications system(s) (DCS) employing programmable digital signal processing circuit for scaling supported communications services
CN106226784B (zh) * 2016-06-27 2019-02-01 广东工业大学 卫星定位增强系统中的参考基站智能动态管理系统及方法
US10141937B2 (en) * 2016-08-09 2018-11-27 Andapt, Inc. Pulse-width modulation (PWM) control loop for power application
JP6790665B2 (ja) * 2016-09-26 2020-11-25 日本電気株式会社 校正回路、校正方法及びプログラム
US10185849B2 (en) 2016-10-07 2019-01-22 Intermec, Inc. Systems and methods for controlling antennas
WO2018067969A1 (en) 2016-10-07 2018-04-12 Nanosemi, Inc. Beam steering digital predistortion
JP6738019B2 (ja) * 2016-10-21 2020-08-12 アイコム株式会社 送信機および歪補正方法
TWI756284B (zh) * 2016-10-27 2022-03-01 美商李爾登公司 用於散佈無線電頭端之系統及方法
US9866269B1 (en) * 2016-11-17 2018-01-09 Xilinx, Inc. Method of and circuit for predistortion for a power amplifier
US10348405B2 (en) * 2016-11-21 2019-07-09 Corning Incorporated Multi-functional units incorporating lighting capabilities in converged networks
US9979422B1 (en) * 2016-12-15 2018-05-22 National Chung Shan Institute Of Science And Technology Adaptive digital pre-distortion system
IT201600131387A1 (it) * 2016-12-27 2018-06-27 Teko Telecom S R L Unita’ radio remota riconfigurabile per sistemi distribuiti d’antenna
JP7068324B2 (ja) 2017-02-15 2022-05-16 メイベン ワイヤレス スウェーデン アクティエボラーグ 冗長性を提供する分散アンテナシステム
KR20190121825A (ko) 2017-02-25 2019-10-28 나노세미, 인크. 멀티밴드 디지털 전치왜곡기
WO2018170862A1 (zh) 2017-03-23 2018-09-27 深圳市大疆创新科技有限公司 飞行器及其外部设备、通信方法、装置与系统
US10135706B2 (en) 2017-04-10 2018-11-20 Corning Optical Communications LLC Managing a communications system based on software defined networking (SDN) architecture
US10141961B1 (en) 2017-05-18 2018-11-27 Nanosemi, Inc. Passive intermodulation cancellation
JP2018207184A (ja) * 2017-05-30 2018-12-27 パナソニックIpマネジメント株式会社 施設内伝送システム、施設内伝送方法及び基地局
CN109039969B (zh) * 2017-06-09 2020-11-27 中国工程物理研究院电子工程研究所 宽带数字预失真器的实现方法
US11115067B2 (en) * 2017-06-09 2021-09-07 Nanosemi, Inc. Multi-band linearization system
US10931318B2 (en) * 2017-06-09 2021-02-23 Nanosemi, Inc. Subsampled linearization system
US10581470B2 (en) 2017-06-09 2020-03-03 Nanosemi, Inc. Linearization system
US10339346B2 (en) 2017-06-26 2019-07-02 Intermec, Inc. Systems and methods for a reconfigurable antenna
US10075201B1 (en) * 2017-07-12 2018-09-11 Intel IP Corporation Adaptive nonlinear system control using robust and low-complexity coefficient estimation
WO2019014422A1 (en) 2017-07-12 2019-01-17 Nanosemi, Inc. SYSTEMS AND METHODS FOR CONTROLLING RADIOS MADE WITH DIGITAL PREDISTORSION
US11012105B2 (en) * 2017-09-12 2021-05-18 Apple Inc. Digital predistortion of signals
WO2019070573A1 (en) 2017-10-02 2019-04-11 Nanosemi, Inc. DIGITAL PREDISTORSION ADJUSTMENT BASED ON DETERMINATION OF CHARGE CHARACTERISTICS
WO2019076513A1 (en) 2017-10-17 2019-04-25 Telefonaktiebolaget Lm Ericsson (Publ) DISTRIBUTED MIMO SYNCHRONIZATION
US11616540B2 (en) 2017-11-21 2023-03-28 Telefonaktiebolaget Lm Ericsson (Publ) Antenna arrangement for distributed massive MIMO
CN108037752B (zh) * 2017-11-30 2020-01-17 中国航空工业集团公司沈阳飞机设计研究所 一种两余度前轮转弯监控方法
CN108235451A (zh) * 2017-12-07 2018-06-29 姬军生 一种一体化便携专网基站系统
CN108063739A (zh) * 2017-12-15 2018-05-22 北京卫星信息工程研究所 宽带数字通信系统发射端功放自适应数字预失真方法
CN108650048B (zh) * 2018-04-03 2019-12-31 广州大学 一种高精度数字阵列多通道延时补偿方法
JP2021523629A (ja) 2018-05-11 2021-09-02 ナノセミ, インク.Nanosemi, Inc. 非線形システム用デジタル補償器
US10644657B1 (en) 2018-05-11 2020-05-05 Nanosemi, Inc. Multi-band digital compensator for a non-linear system
JP2019201361A (ja) * 2018-05-17 2019-11-21 富士通株式会社 歪補償装置および歪補償方法
US10931238B2 (en) 2018-05-25 2021-02-23 Nanosemi, Inc. Linearization with envelope tracking or average power tracking
US11863210B2 (en) 2018-05-25 2024-01-02 Nanosemi, Inc. Linearization with level tracking
CN112640299A (zh) 2018-05-25 2021-04-09 纳诺塞米有限公司 变化操作条件下的数字预失真
KR102452622B1 (ko) * 2018-06-11 2022-10-07 삼성전자주식회사 등화기 및 이를 포함하는 송신기
US10791475B2 (en) * 2018-11-06 2020-09-29 Corning Optical Communications LLC Systems and methods for performance evaluations in distributed antenna systems (DASs)
DE102018220089A1 (de) * 2018-11-22 2020-05-28 Infineon Technologies Ag Digitale Vorverzerrungstechnik für eine Schaltungsanordnung mit einem Leistungsverstärker
US10985951B2 (en) 2019-03-15 2021-04-20 The Research Foundation for the State University Integrating Volterra series model and deep neural networks to equalize nonlinear power amplifiers
CN110289869B (zh) * 2019-05-25 2021-01-01 西南电子技术研究所(中国电子科技集团公司第十研究所) 超短波功放数字预失真模型
US11405582B2 (en) 2019-06-28 2022-08-02 Meta Platforms, Inc. Preprocessing of high-dynamic-range video using a hybrid lookup table scheme
US10887079B1 (en) 2019-09-26 2021-01-05 Corning Research & Development Corporation Digital predistortion (DPD) timing alignment in a remote unit(s) for a wireless communications system (WCS)
US11418277B2 (en) * 2019-11-15 2022-08-16 Solid, Inc. Optical communication system and method of monitoring thereof
JP2023502393A (ja) * 2019-11-18 2023-01-24 コムスコープ テクノロジーズ リミティド ライアビリティ カンパニー マルチオペレータ分散アンテナシステムのためのシステムおよび方法
US20230155632A1 (en) * 2020-04-24 2023-05-18 Telefonaktiebolaget Lm Ericsson (Publ) Failsafe Series-Connected Radio System
US10992326B1 (en) 2020-05-19 2021-04-27 Nanosemi, Inc. Buffer management for adaptive digital predistortion
US11190230B1 (en) 2020-05-29 2021-11-30 Corning Research & Development Corporation Wide bandwidth digital pre-distortion (DPD) in a remote unit(s) for a wireless communications system (WCS)
US20220021406A1 (en) * 2020-07-14 2022-01-20 Intel Corporation Concept for an RF Frontend
CN112583370B (zh) * 2020-12-10 2023-03-21 中国工程物理研究院电子工程研究所 一种具有高效率和高线性度的功率放大装置
US11251819B1 (en) * 2020-12-23 2022-02-15 Xilinx, Inc. Thermal effect mitigation for digital pre-distortion
US11818808B2 (en) 2021-01-29 2023-11-14 Dali Systems Co. Ltd. Redundant distributed antenna system (DAS) with failover capability
CN112996019B (zh) * 2021-03-01 2021-08-27 军事科学院系统工程研究院网络信息研究所 基于多目标优化的太赫兹频段分布式星群接入控制方法
WO2022185505A1 (ja) * 2021-03-05 2022-09-09 三菱電機株式会社 歪み補償回路のための学習装置、及び歪み補償回路
US11942899B2 (en) 2021-06-18 2024-03-26 Qorvo Us, Inc. Envelope tracking voltage correction in a transmission circuit
IL311085A (en) * 2021-08-27 2024-04-01 Aciist Smart Networks Ltd Implementation of a two-switch distributed layer
US11906992B2 (en) 2021-09-16 2024-02-20 Qorvo Us, Inc. Distributed power management circuit
US20230080621A1 (en) * 2021-09-16 2023-03-16 Qorvo Us, Inc. Phase and amplitude error correction in a transmission circuit
CN114421902B (zh) * 2022-01-21 2023-06-06 上海物骐微电子有限公司 适用于WiFi无记忆功放的预失真校准方法及应用
CN114520993B (zh) * 2022-03-08 2024-01-05 沈阳中科奥维科技股份有限公司 基于信道质量监测的无线传输系统网络自优化方法
CN115278746B (zh) * 2022-07-28 2023-03-28 北京邮电大学 面向5g宽带功放的自适应快速误差修正数字预失真方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6054896A (en) * 1998-12-17 2000-04-25 Datum Telegraphic Inc. Controller and associated methods for a linc linear power amplifier

Family Cites Families (516)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4700151A (en) * 1985-03-20 1987-10-13 Nec Corporation Modulation system capable of improving a transmission system
US4638248A (en) * 1985-06-10 1987-01-20 Massachusetts Institute Of Technology Methods and apparatus for measuring relative gain and phase of voltage input signals versus voltage output signals
DE3604893A1 (de) 1986-02-15 1987-08-20 Honeywell Elac Nautik Gmbh Verfahren und vorrichtung zum feststellen geringfuegiger mengen von gasen oder daempfen in gasgemischen
US4755795A (en) 1986-10-31 1988-07-05 Hewlett-Packard Company Adaptive sample rate based on input signal bandwidth
GB2204202B (en) * 1987-04-28 1991-11-27 Racal Communications Equip Radio transmitters
GB8826476D0 (en) 1988-11-11 1988-12-14 British Telecomm Communications system
US5121412A (en) * 1989-01-03 1992-06-09 Motorola, Inc. All-digital quadrature modulator
US4929906A (en) * 1989-01-23 1990-05-29 The Boeing Company Amplifier linearization using down/up conversion
FR2642243B1 (fr) 1989-01-24 1991-04-19 Labo Electronique Physique Circuit de predistorsion adaptative
US5132639A (en) * 1989-09-07 1992-07-21 Ortel Corporation Predistorter for linearization of electronic and optical signals
FR2652965A1 (fr) 1989-10-06 1991-04-12 Philips Electronique Lab Dispositif de predistorsion pour systeme de transmission numerique.
US4999831A (en) 1989-10-19 1991-03-12 United Telecommunications, Inc. Synchronous quantized subcarrier multiplexer for digital transport of video, voice and data
US5049832A (en) * 1990-04-20 1991-09-17 Simon Fraser University Amplifier linearization by adaptive predistortion
JPH04207532A (ja) 1990-11-30 1992-07-29 Nippon Telegr & Teleph Corp <Ntt> 通信装置
US5678198A (en) * 1991-05-22 1997-10-14 Southwestern Bell Technology Resources, Inc. System for controlling signal level at both ends of a transmission link, based upon a detected value
CA2066540C (en) 1991-06-13 1998-01-20 Edwin A. Kelley Multiple user digital receiving apparatus and method with time division multiplexing
JPH05136724A (ja) 1991-11-15 1993-06-01 A T R Koudenpa Tsushin Kenkyusho:Kk 移動体無線通信システム
GB2268364B (en) 1992-06-25 1995-10-11 Roke Manor Research Improvements in or relating to radio communication systems
US5627879A (en) 1992-09-17 1997-05-06 Adc Telecommunications, Inc. Cellular communications system with centralized base stations and distributed antenna units
JP2883260B2 (ja) * 1993-04-20 1999-04-19 三菱電機株式会社 歪補償回路
JP3156439B2 (ja) 1993-04-20 2001-04-16 三菱電機株式会社 歪補償回路
US7924783B1 (en) 1994-05-06 2011-04-12 Broadcom Corporation Hierarchical communications system
US5619202A (en) 1994-11-22 1997-04-08 Analog Devices, Inc. Variable sample rate ADC
IT1265271B1 (it) 1993-12-14 1996-10-31 Alcatel Italia Sistema di predistorsione in banda base per la linearizzazione adattativa di amplificatori di potenza
US5457557A (en) 1994-01-21 1995-10-10 Ortel Corporation Low cost optical fiber RF signal distribution system
US5452473A (en) 1994-02-28 1995-09-19 Qualcomm Incorporated Reverse link, transmit power correction and limitation in a radiotelephone system
US5973011A (en) 1994-03-30 1999-10-26 Isis Pharma Gmbh Pharmaceutical preparations and medicaments for the prevention and treatment of endothelial dysfunction
US5579342A (en) * 1994-09-22 1996-11-26 Her Majesty The Queen In Right Of Canada As Represented By The Minister Of Communications Pre-compensated frequency modulation (PFM)
US5748683A (en) 1994-12-29 1998-05-05 Motorola, Inc. Multi-channel transceiver having an adaptive antenna array and method
US5579341A (en) 1994-12-29 1996-11-26 Motorola, Inc. Multi-channel digital transceiver and method
US5486789A (en) * 1995-02-28 1996-01-23 Motorola, Inc. Apparatus and method for providing a baseband digital error signal in an adaptive predistorter
JP2967699B2 (ja) 1995-03-06 1999-10-25 日本電気株式会社 送信装置
US5596600A (en) * 1995-04-06 1997-01-21 Mayflower Communications Company, Inc. Standalone canceller of narrow band interference for spread spectrum receivers
FI98014C (fi) * 1995-06-30 1997-03-25 Nokia Mobile Phones Ltd Kuutiointipiiri signaalin esisäröyttämiseksi
US5870668A (en) 1995-08-18 1999-02-09 Fujitsu Limited Amplifier having distortion compensation and base station for radio communication using the same
US6356555B1 (en) 1995-08-25 2002-03-12 Terayon Communications Systems, Inc. Apparatus and method for digital data transmission using orthogonal codes
US5903823A (en) * 1995-09-19 1999-05-11 Fujitsu Limited Radio apparatus with distortion compensating function
US5589797A (en) 1995-09-26 1996-12-31 Lucent Technologies Inc. Low distortion amplifier
US6005884A (en) 1995-11-06 1999-12-21 Ems Technologies, Inc. Distributed architecture for a wireless data communications system
US5794153A (en) 1995-12-26 1998-08-11 Lucent Technologies Inc. Estimating PCS traffic from radio port measurements
US5675287A (en) * 1996-02-12 1997-10-07 Motorola, Inc. Digital DC correction circuit for a linear transmitter
US5880863A (en) 1996-02-13 1999-03-09 Gte Laboratories Incorporated Reconfigurable ring system for the transport of RF signals over optical fibers
US5732333A (en) * 1996-02-14 1998-03-24 Glenayre Electronics, Inc. Linear transmitter using predistortion
US5937011A (en) * 1996-03-26 1999-08-10 Airnet Communications Corp. Multi-carrier high power amplifier using digital pre-distortion
US5740520A (en) 1996-04-03 1998-04-14 State Of Israel Channel correction transceiver
JP2738385B2 (ja) 1996-04-15 1998-04-08 日本電気株式会社 可変帯域幅周波数分割多重通信方式
JPH09284149A (ja) 1996-04-17 1997-10-31 Nec Corp 電力増幅部の自動利得制御回路
US5831479A (en) 1996-06-13 1998-11-03 Motorola, Inc. Power delivery system and method of controlling the power delivery system for use in a radio frequency system
EP0885482B1 (de) 1996-06-19 1999-08-04 Fraunhofer-Gesellschaft Zur Förderung Der Angewandten Forschung E.V. Vorverzerrung für eine nichtlineare übertragungsstrecke im hochfrequenzbereich
US5757229A (en) * 1996-06-28 1998-05-26 Motorola, Inc. Bias circuit for a power amplifier
US6023612A (en) * 1996-07-05 2000-02-08 Thomcast Communications, Inc. Modular transmission system and method
US5898338A (en) * 1996-09-20 1999-04-27 Spectrian Adaptive digital predistortion linearization and feed-forward correction of RF power amplifier
US6493335B1 (en) * 1996-09-24 2002-12-10 At&T Corp. Method and system for providing low-cost high-speed data services
FR2755335B1 (fr) 1996-10-24 1998-11-27 Alsthom Cge Alcatel Estimateur du defaut de balance d'un modulateur en quadrature et etage de modulation l'utilisant
US6205133B1 (en) 1996-11-25 2001-03-20 Ericsson Inc. Flexible wideband architecture for use in radio communications systems
US5920808A (en) 1996-12-12 1999-07-06 Glenayre Electronics, Inc. Method and apparatus for reducing key-up distortion by pre-heating transistors
US6246865B1 (en) * 1997-02-04 2001-06-12 Samsung Electronics Co., Ltd. Device and method for controlling distortion characteristic of predistorter
US6112086A (en) 1997-02-25 2000-08-29 Adc Telecommunications, Inc. Scanning RSSI receiver system using inverse fast fourier transforms for a cellular communications system with centralized base stations and distributed antenna units
US5923712A (en) 1997-05-05 1999-07-13 Glenayre Electronics, Inc. Method and apparatus for linear transmission by direct inverse modeling
KR100307665B1 (ko) 1997-05-23 2001-10-19 하재홍 전자정보키시스템
US6072364A (en) 1997-06-17 2000-06-06 Amplix Adaptive digital predistortion for power amplifiers with real time modeling of memoryless complex gains
KR100251561B1 (ko) 1997-06-19 2000-04-15 윤종용 디지털통신시스템의송신기선형화장치및방법
US5810888A (en) 1997-06-26 1998-09-22 Massachusetts Institute Of Technology Thermodynamic adaptive phased array system for activating thermosensitive liposomes in targeted drug delivery
US6081158A (en) 1997-06-30 2000-06-27 Harris Corporation Adaptive pre-distortion apparatus for linearizing an amplifier output within a data transmission system
US6639050B1 (en) * 1997-07-21 2003-10-28 Ohio University Synthetic genes for plant gums and other hydroxyproline-rich glycoproteins
US6252461B1 (en) * 1997-08-25 2001-06-26 Frederick Herbert Raab Technique for wideband operation of power amplifiers
US5959499A (en) * 1997-09-30 1999-09-28 Motorola, Inc. Predistortion system and method using analog feedback loop for look-up table training
US6393007B1 (en) 1997-10-16 2002-05-21 Telefonaktiebolaget Lm Ericsson (Publ) Method of and a system for voice and data radio communication providing improved interference diversity
US5936464A (en) * 1997-11-03 1999-08-10 Motorola, Inc. Method and apparatus for reducing distortion in a high efficiency power amplifier
US6005506A (en) 1997-12-09 1999-12-21 Qualcomm, Incorporated Receiver with sigma-delta analog-to-digital converter for sampling a received signal
JP3171157B2 (ja) * 1997-12-10 2001-05-28 松下電器産業株式会社 非線形歪補償装置
US5963549A (en) * 1997-12-10 1999-10-05 L-3 Communications Corporation Fixed wireless loop system having baseband combiner predistortion summing table
US6252912B1 (en) 1997-12-24 2001-06-26 General Dynamics Government Systems Corporation Adaptive predistortion system
US5959500A (en) 1998-01-26 1999-09-28 Glenayre Electronics, Inc. Model-based adaptive feedforward amplifier linearizer
GB9804835D0 (en) 1998-03-06 1998-04-29 Wireless Systems Int Ltd Predistorter
US6215354B1 (en) 1998-03-06 2001-04-10 Fujant, Inc. Closed loop calibration for an amplitude reconstruction amplifier
US6300956B1 (en) * 1998-03-17 2001-10-09 Pixar Animation Stochastic level of detail in computer animation
US6288610B1 (en) 1998-03-19 2001-09-11 Fujitsu Limited Method and apparatus for correcting signals, apparatus for compensating for distortion, apparatus for preparing distortion compensating data, and transmitter
FI105506B (fi) * 1998-04-30 2000-08-31 Nokia Networks Oy Vahvistimen linearisointimenetelmä ja vahvistinjärjestely
US5999990A (en) 1998-05-18 1999-12-07 Motorola, Inc. Communicator having reconfigurable resources
GB9811381D0 (en) 1998-05-27 1998-07-22 Nokia Mobile Phones Ltd Predistortion control for power reduction
US6373611B1 (en) 1998-06-22 2002-04-16 Scientific-Atlanta, Inc. Digital optical transmitter
US6600792B2 (en) * 1998-06-26 2003-07-29 Qualcomm Incorporated Predistortion technique for high power amplifiers
US6266531B1 (en) 1998-07-01 2001-07-24 Ericsson Inc. System and method for adaptive thresholds for cell load sharing
US6253094B1 (en) 1998-07-09 2001-06-26 Airnet Communications Corporation Sectorized cell having non-redundant broadband processing unit
KR100326176B1 (ko) * 1998-08-06 2002-04-17 윤종용 이동통신시스템의전력증폭장치및방법
US6124758A (en) 1998-08-19 2000-09-26 Harris Corporation RF power amplifier control system
US6430402B1 (en) 1998-09-14 2002-08-06 Conexant Systems, Inc. Power amplifier saturation prevention method, apparatus, and communication system incorporating the same
US6594253B1 (en) 1998-09-29 2003-07-15 Ericsson Inc. System and method for mobility management for an internet telephone call to a mobile terminal
US6315189B1 (en) 1998-10-13 2001-11-13 Texas Instruments Incorporated Semiconductor package lead plating method and apparatus
US6301579B1 (en) * 1998-10-20 2001-10-09 Silicon Graphics, Inc. Method, system, and computer program product for visualizing a data structure
WO2000023956A1 (en) 1998-10-22 2000-04-27 University Of Maryland Method and system for providing location dependent and personal identification information to a public safety answering point
FI105612B (fi) 1998-10-23 2000-09-15 Nokia Networks Oy Menetelmä ja kytkentä vaihevirheen korjaamiseksi tehovahvistimen linearisointisilmukassa
US6275685B1 (en) * 1998-12-10 2001-08-14 Nortel Networks Limited Linear amplifier arrangement
KR20000039780A (ko) 1998-12-16 2000-07-05 김영환 알티유를 이용한 디지털-주파수 공용통신 기지국 감시제어 시스템
US6236267B1 (en) 1998-12-29 2001-05-22 International Business Machines Corporation Linearization for power amplifiers using feed-forward and feedback control
US6166601A (en) 1999-01-07 2000-12-26 Wiseband Communications Ltd. Super-linear multi-carrier power amplifier
US6356369B1 (en) 1999-02-22 2002-03-12 Scientific-Atlanta, Inc. Digital optical transmitter for processing externally generated information in the reverse path
JP2000278237A (ja) 1999-03-25 2000-10-06 Toshiba Corp Ofdm用中継装置
FI990680A (fi) 1999-03-26 2000-09-27 Nokia Networks Oy I/Q-modulaattorin epälineaarisuuden korjaus
JP2000278166A (ja) 1999-03-26 2000-10-06 Nec Corp ソフトウエア携帯電話機
GB2348755B (en) 1999-04-01 2001-03-07 Wireless Systems Int Ltd Signal processing
US6657993B1 (en) * 1999-05-11 2003-12-02 Lucent Technologies Inc. System and method for variable bandwidth transmission facilities between a local telephone switch and a remote line unit
US6614854B1 (en) 1999-05-28 2003-09-02 Carriercomm, Inc. System and method for adaptive predistortion
IT1313906B1 (it) 1999-06-15 2002-09-26 Cit Alcatel Precorrezione digitale adattiva di non-linearita' introdotte daamplicatori di potenza.
US6724737B1 (en) 1999-06-17 2004-04-20 Lockheed Martin Global Telecommunications, Inc System for controlling communications between a terminal and satellite and method therefore
GB2351624B (en) * 1999-06-30 2003-12-03 Wireless Systems Int Ltd Reducing distortion of signals
JP2001016116A (ja) * 1999-07-02 2001-01-19 Nec Corp 携帯無線機
US6697436B1 (en) * 1999-07-13 2004-02-24 Pmc-Sierra, Inc. Transmission antenna array system with predistortion
US6587514B1 (en) 1999-07-13 2003-07-01 Pmc-Sierra, Inc. Digital predistortion methods for wideband amplifiers
US6356146B1 (en) * 1999-07-13 2002-03-12 Pmc-Sierra, Inc. Amplifier measurement and modeling processes for use in generating predistortion parameters
US7409007B1 (en) 1999-09-14 2008-08-05 Lucent Technologies Inc. Method and apparatus for reducing adjacent channel power in wireless communication systems
EP1085773A1 (en) 1999-09-20 2001-03-21 Nortel Matra Cellular Mobile telecommunications network with distributed base stations
US6246286B1 (en) * 1999-10-26 2001-06-12 Telefonaktiebolaget Lm Ericsson Adaptive linearization of power amplifiers
JP3381689B2 (ja) 1999-11-30 2003-03-04 日本電気株式会社 非線形歪み補償回路及びそれを用いた送信装置並びに移動通信機
US7257328B2 (en) 1999-12-13 2007-08-14 Finisar Corporation System and method for transmitting data on return path of a cable television system
US6697603B1 (en) 1999-12-13 2004-02-24 Andrew Corporation Digital repeater
JP4183364B2 (ja) 1999-12-28 2008-11-19 富士通株式会社 歪補償装置
JP4014343B2 (ja) 1999-12-28 2007-11-28 富士通株式会社 歪補償装置
US6751447B1 (en) * 1999-12-30 2004-06-15 Samsung Electronics Cop., Ltd. Adaptive digital pre-distortion circuit using output reference signal and method of operation
US7260620B1 (en) 2000-01-05 2007-08-21 Cisco Technology, Inc. System for selecting the operating frequency of a communication device in a wireless network
US6359504B1 (en) 2000-01-28 2002-03-19 Lucent Technologies Inc. Power amplifier using upstream signal information
WO2001056197A2 (en) 2000-01-28 2001-08-02 Scientific-Atlanta, Inc. Digital downstream communication system
JP3578957B2 (ja) 2000-02-03 2004-10-20 株式会社日立国際電気 増幅装置
US6242979B1 (en) * 2000-02-23 2001-06-05 Motorola, Inc. Linearization using parallel cancellation in linear power amplifier
GB2359679B (en) 2000-02-24 2004-03-10 Wireless Systems Int Ltd Amplifier
GB2359681B (en) 2000-02-25 2004-03-10 Wireless Systems Int Ltd Switched amplifier
JP4346200B2 (ja) 2000-03-17 2009-10-21 株式会社東芝 地上波放送制御システム
DE60139116D1 (de) 2000-03-27 2009-08-13 Opencell Corp System zum Verteilen von Multiprotokoll-RF-Signalen
US6741662B1 (en) 2000-04-17 2004-05-25 Intel Corporation Transmitter linearization using fast predistortion
US6980527B1 (en) 2000-04-25 2005-12-27 Cwill Telecommunications, Inc. Smart antenna CDMA wireless communication system
AU2001239934A1 (en) 2000-04-27 2001-11-12 Lgc Wireless, Inc. Adaptive capacity management in a centralized basestation architecture
US6353600B1 (en) 2000-04-29 2002-03-05 Lgc Wireless, Inc. Dynamic sectorization in a CDMA cellular system employing centralized base-station architecture
GB0011326D0 (en) * 2000-05-11 2000-06-28 Nortel Networks Corp A linear amplifier arrangement
DE10025287B4 (de) * 2000-05-22 2006-06-08 Siemens Ag Verfahren und Kommunikationssystem zur Schätzung einer Störungs-Kovarianzmatrix für die Abwärtsverbindung in zellularen Mobilfunknetzen mit adaptiven Antennen
US6489846B2 (en) 2000-05-25 2002-12-03 Sony Corporation Distortion compensating device and distortion compensating method
JP4326673B2 (ja) 2000-06-06 2009-09-09 富士通株式会社 非線形歪補償装置を有する通信装置の起動方法
JP2002009557A (ja) 2000-06-21 2002-01-11 Matsushita Electric Ind Co Ltd 線形補償増幅装置
US6704545B1 (en) 2000-07-19 2004-03-09 Adc Telecommunications, Inc. Point-to-multipoint digital radio frequency transport
US6898252B1 (en) 2000-07-21 2005-05-24 Intel Corporation IQ mismatch cancellation
US6351189B1 (en) 2000-07-31 2002-02-26 Nokia Networks Oy System and method for auto-bias of an amplifier
US6804540B1 (en) 2000-08-02 2004-10-12 Ericsson Inc. Remote band-pass filter in a distributed antenna system
US6639463B1 (en) 2000-08-24 2003-10-28 Lucent Technologies Inc. Adaptive power amplifier system and method
JP3590571B2 (ja) * 2000-08-30 2004-11-17 株式会社日立国際電気 歪補償装置
US6445688B1 (en) 2000-08-31 2002-09-03 Ricochet Networks, Inc. Method and apparatus for selecting a directional antenna in a wireless communication system
FR2813487B1 (fr) 2000-08-31 2002-11-29 Cit Alcatel Procede et dispositif de controle de l'amplification du signal emis par un terminal mobile permettant d'augmenter l'autonomie dudit terminal mobile
KR100374828B1 (ko) * 2000-09-15 2003-03-04 엘지전자 주식회사 적응성 전치왜곡 송신기
WO2002023956A2 (en) 2000-09-15 2002-03-21 Teledyne Lighting And Display Products, Inc. Power supply for light emitting diodes
DE10046059A1 (de) 2000-09-18 2002-03-28 Oskar Bschorr Flachlautsprecher
JP2002111401A (ja) 2000-10-03 2002-04-12 Fujitsu Ltd 信号の歪補償装置および歪補償方法
AU2002249827A1 (en) 2000-10-27 2002-07-24 Chameleon Systems, Inc. System and method of implementing a wireless communication system using a reconfigurable chip with a reconfigurable fabric
CA2362104A1 (en) 2000-10-30 2002-04-30 Simon Fraser University High efficiency power amplifier systems and methods
US20020179830A1 (en) * 2000-11-01 2002-12-05 Pearson Robert M. Halbach Dipole magnet shim system
US7072650B2 (en) 2000-11-13 2006-07-04 Meshnetworks, Inc. Ad hoc peer-to-peer mobile radio access system interfaced to the PSTN and cellular networks
JP3388409B2 (ja) 2000-11-22 2003-03-24 国土交通省国土技術政策総合研究所長 路側通信網
US6424225B1 (en) * 2000-11-27 2002-07-23 Conexant Systems, Inc. Power amplifier circuit for providing constant bias current over a wide temperature range
US7016332B2 (en) 2000-12-05 2006-03-21 Science Applications International Corporation Method and system for a remote downlink transmitter for increasing the capacity of a multiple access interference limited spread-spectrum wireless network
US6907490B2 (en) 2000-12-13 2005-06-14 Intel Corporation Method and an apparatus for a re-configurable processor
GB2370170B (en) * 2000-12-15 2003-01-29 Ntl Group Ltd Signal transmission systems
KR20020054149A (ko) * 2000-12-27 2002-07-06 엘지전자 주식회사 디지털 전치왜곡기를 갖는 기지국 송신장치
KR100459412B1 (ko) 2000-12-28 2004-12-03 엘지전자 주식회사 디지털 신호 전송장치를 이용한 cdma 광 중계기 수신장치
US6901256B2 (en) 2000-12-29 2005-05-31 Sprint Spectrum L.P. Cellular/PCS CDMA system with pilot beacons for call handoffs
US6801767B1 (en) * 2001-01-26 2004-10-05 Lgc Wireless, Inc. Method and system for distributing multiband wireless communications signals
JP3690988B2 (ja) * 2001-02-01 2005-08-31 株式会社日立国際電気 プリディストーション歪み補償装置
US7145704B1 (en) 2003-11-25 2006-12-05 Cheetah Omni, Llc Optical logic gate based optical router
KR100398664B1 (ko) * 2001-02-21 2003-09-19 주식회사 쏠리테크 중간주파수 대역 사전왜곡에 의한 전력 증폭기 선형화 장치
US6983025B2 (en) * 2001-04-11 2006-01-03 Tropian, Inc. High quality power ramping in a communications transmitter
WO2002091692A1 (en) 2001-04-13 2002-11-14 Girard Gregory D Ditributed edge switching system for voice-over-packet multiservice network
WO2002087097A1 (fr) 2001-04-18 2002-10-31 Fujitsu Limited Dispositif de correction de distorsion
US6404284B1 (en) 2001-04-19 2002-06-11 Anadigics, Inc. Amplifier bias adjustment circuit to maintain high-output third-order intermodulation distortion performance
US9893774B2 (en) 2001-04-26 2018-02-13 Genghiscomm Holdings, LLC Cloud radio access network
IL158986A0 (en) * 2001-05-31 2004-05-12 Magnolia Broadband Inc Communication device with smart antenna using a quality-indication signal
US6903604B2 (en) 2001-06-07 2005-06-07 Lucent Technologies Inc. Method and apparatus for modeling and estimating the characteristics of a power amplifier
US6928122B2 (en) 2001-06-07 2005-08-09 Motorola, Inc. Amplifier predistortion system and method
US20020191565A1 (en) 2001-06-08 2002-12-19 Sanjay Mani Methods and systems employing receive diversity in distributed cellular antenna applications
US7035345B2 (en) * 2001-06-08 2006-04-25 Polyvalor S.E.C. Adaptive predistortion device and method using digital receiver
US7127175B2 (en) 2001-06-08 2006-10-24 Nextg Networks Method and apparatus for multiplexing in a wireless communication infrastructure
CN1290358C (zh) 2001-06-08 2006-12-13 耐克斯特格网络公司 在使用空间分集的无线通信网络内将天线连接至基站的网络和方法
US6826164B2 (en) 2001-06-08 2004-11-30 Nextg Networks Method and apparatus for multiplexing in a wireless communication infrastructure
GB2376583B (en) * 2001-06-15 2005-01-05 Wireless Systems Int Ltd Time alignment of signals
US7068984B2 (en) * 2001-06-15 2006-06-27 Telefonaktiebolaget Lm Ericsson (Publ) Systems and methods for amplification of a communication signal
US7203247B2 (en) 2001-07-23 2007-04-10 Agere Systems Inc. Digital predistortion technique for WCDMA wireless communication system and method of operation thereof
KR100422133B1 (ko) 2001-07-27 2004-03-12 엘지전자 주식회사 광대역 무선가입자망 시스템의 패킷데이터 처리장치 및 그방법
EP1282328A1 (de) 2001-07-27 2003-02-05 Alcatel Verfahren zum Aufbau von Telekommunikationsverbindungen im Anschlussbereich einer Teilnehmervermittlungsstelle, Teilnehmeranschlusssystem, Teilnehmervermittlungsstelle und Vorfeldeinrichtung
US7158765B2 (en) * 2001-07-31 2007-01-02 Agere Systems, Inc. Method and apparatus for controlling power of a transmitted signal
US20030058959A1 (en) 2001-09-25 2003-03-27 Caly Networks. Combined digital adaptive pre-distorter and pre-equalizer system for modems in link hopping radio networks
US8446530B2 (en) 2001-09-28 2013-05-21 Entropic Communications, Inc. Dynamic sampling
US7109998B2 (en) * 2001-10-03 2006-09-19 Sun Microsystems, Inc. Stationary semantic zooming
KR100835847B1 (ko) 2001-10-10 2008-06-05 텔레포나크티에볼라게트 엘엠 에릭슨(피유비엘) 디지털 데이터 복구 방법과 회로
US7103329B1 (en) * 2001-10-25 2006-09-05 Rockwell Collins, Inc. Adaptive feedback channel for radio frequency power amplifiers
SE520466C2 (sv) * 2001-11-12 2003-07-15 Ericsson Telefon Ab L M Metod och anordning vid en digital linjäriseringskoppling
US7058139B2 (en) * 2001-11-16 2006-06-06 Koninklijke Philips Electronics N.V. Transmitter with transmitter chain phase adjustment on the basis of pre-stored phase information
US6657510B2 (en) 2001-11-27 2003-12-02 Harris Corporation Corrective phase quadrature modulator system and method
US8396368B2 (en) 2009-12-09 2013-03-12 Andrew Llc Distributed antenna system for MIMO signals
JP2003168931A (ja) 2001-12-04 2003-06-13 Nec Corp 歪補償回路
US6703897B2 (en) * 2001-12-26 2004-03-09 Nortel Networks Limited Methods of optimising power amplifier efficiency and closed-loop power amplifier controllers
US7339891B2 (en) 2002-01-09 2008-03-04 Mverify Corporation Method and system for evaluating wireless applications
US6993302B2 (en) * 2002-01-15 2006-01-31 Igor Bausov Class-L power-output amplifier
US7079818B2 (en) * 2002-02-12 2006-07-18 Broadcom Corporation Programmable mutlistage amplifier and radio applications thereof
JP3972664B2 (ja) 2002-01-23 2007-09-05 日本電気株式会社 パス障害回復方式及び障害復旧後の切戻方式並びにそれらを用いるノード
KR100553252B1 (ko) * 2002-02-01 2006-02-20 아바고테크놀로지스코리아 주식회사 휴대용 단말기의 전력 증폭 장치
US7248642B1 (en) * 2002-02-05 2007-07-24 Andrew Corporation Frequency-dependent phase pre-distortion for reducing spurious emissions in communication networks
US6731168B2 (en) 2002-02-06 2004-05-04 Intersil Americas, Inc. Power amplifier linearizer that compensates for long-time-constant memory effects and method therefor
US6566944B1 (en) 2002-02-21 2003-05-20 Ericsson Inc. Current modulator with dynamic amplifier impedance compensation
US7339897B2 (en) 2002-02-22 2008-03-04 Telefonaktiebolaget Lm Ericsson (Publ) Cross-layer integrated collision free path routing
US6882833B2 (en) * 2002-02-22 2005-04-19 Blue7 Communications Transferring data in a wireless communication system
US7197085B1 (en) 2002-03-08 2007-03-27 Andrew Corporation Frequency-dependent magnitude pre-distortion for reducing spurious emissions in communication networks
US6983026B2 (en) * 2002-03-19 2006-01-03 Motorola, Inc. Method and apparatus using base band transformation to improve transmitter performance
US6747649B1 (en) * 2002-03-19 2004-06-08 Aechelon Technology, Inc. Terrain rendering in a three-dimensional environment
US7489632B2 (en) 2002-03-22 2009-02-10 Nokia Corporation Simple admission control for IP based networks
US20030179830A1 (en) * 2002-03-25 2003-09-25 Eidson Donald B. Efficient, high fidelity transmission of modulation schemes through power-constrained remote relay stations by local transmit predistortion and local receiver feedback
WO2003081870A1 (en) 2002-03-26 2003-10-02 Her Majesty In Right Of Canada As Represented By The Minister Of Industry Adaptive predistorter based on the probability distribution function of the output amplitude
JP4071526B2 (ja) 2002-04-10 2008-04-02 松下電器産業株式会社 非線形歪補償装置および送信装置
US6985704B2 (en) 2002-05-01 2006-01-10 Dali Yang System and method for digital memorized predistortion for wireless communication
US8380143B2 (en) 2002-05-01 2013-02-19 Dali Systems Co. Ltd Power amplifier time-delay invariant predistortion methods and apparatus
US8472897B1 (en) 2006-12-22 2013-06-25 Dali Systems Co. Ltd. Power amplifier predistortion methods and apparatus
US8811917B2 (en) 2002-05-01 2014-08-19 Dali Systems Co. Ltd. Digital hybrid mode power amplifier system
US8064850B2 (en) 2002-05-01 2011-11-22 Dali Systems Co., Ltd. High efficiency linearization power amplifier for wireless communication
JP2003347854A (ja) 2002-05-29 2003-12-05 Matsushita Electric Ind Co Ltd 電力増幅器
US6831901B2 (en) 2002-05-31 2004-12-14 Opencell Corporation System and method for retransmission of data
JP4077449B2 (ja) * 2002-05-31 2008-04-16 富士通株式会社 テーブル参照型プリディストータ
KR100448892B1 (ko) 2002-06-04 2004-09-18 한국전자통신연구원 고전력 증폭기의 비선형 왜곡 보상을 위한 전치 왜곡 장치및 그 방법
JP2004015364A (ja) 2002-06-06 2004-01-15 Fujitsu Ltd 歪補償機能を有する送信装置及び歪補償タイミング調整方法
US7139327B2 (en) 2002-06-10 2006-11-21 Andrew Corporation Digital pre-distortion of input signals for reducing spurious emissions in communication networks
US7493094B2 (en) 2005-01-19 2009-02-17 Micro Mobio Corporation Multi-mode power amplifier module for wireless communication devices
KR100486547B1 (ko) 2002-12-18 2005-05-03 엘지전자 주식회사 전력증폭기의 전치왜곡 보상장치 및 방법
US7034612B2 (en) 2002-07-20 2006-04-25 Lg Electronics Inc. Apparatus and method for compensating pre-distortion of a power amplifier
US7113551B2 (en) * 2002-07-25 2006-09-26 Intersil Corporation Transmitter with limited spectral regrowth and method therefor
US7321635B2 (en) * 2002-08-16 2008-01-22 Andrew Corporation Linearization of amplifiers using baseband detection and non-baseband pre-distortion
US7493129B1 (en) 2002-09-12 2009-02-17 At&T Mobility Ii Llc Method and apparatus to maintain network coverage when using a transport media to communicate with a remote antenna
US20040053624A1 (en) 2002-09-17 2004-03-18 Frank Ed H. Method and system for optimal load balancing in a hybrid wired/wireless network
JP4546711B2 (ja) 2002-10-07 2010-09-15 パナソニック株式会社 通信装置
US7151913B2 (en) * 2003-06-30 2006-12-19 M/A-Com, Inc. Electromagnetic wave transmitter, receiver and transceiver systems, methods and articles of manufacture
JP4124710B2 (ja) 2002-10-17 2008-07-23 松下電器産業株式会社 無線通信システム
JP2004147009A (ja) 2002-10-23 2004-05-20 Hitachi Kokusai Electric Inc 中継増幅装置
DE60235127D1 (de) * 2002-10-31 2010-03-04 Zte Corp Verfahren und system für breitband-vorverzerrungslinearisierung
US7047028B2 (en) 2002-11-15 2006-05-16 Telefonaktiebolaget Lm Ericsson (Publ) Optical fiber coupling configurations for a main-remote radio base station and a hybrid radio base station
US7206355B2 (en) 2002-12-02 2007-04-17 Nortel Networks Limited Digitally convertible radio
US7103377B2 (en) 2002-12-03 2006-09-05 Adc Telecommunications, Inc. Small signal threshold and proportional gain distributed digital communications
US8958789B2 (en) 2002-12-03 2015-02-17 Adc Telecommunications, Inc. Distributed digital antenna system
US6785558B1 (en) 2002-12-06 2004-08-31 Lgc Wireless, Inc. System and method for distributing wireless communication signals over metropolitan telecommunication networks
EP1576779B1 (en) 2002-12-24 2015-12-09 Telecom Italia S.p.A. Radio base station receiver having digital filtering and reduced sampling frequency
KR100480278B1 (ko) 2002-12-24 2005-04-07 삼성전자주식회사 광대역 전력 증폭기를 위한 디지털 전치보상기 및 그적응화 방법
US7403573B2 (en) 2003-01-15 2008-07-22 Andrew Corporation Uncorrelated adaptive predistorter
US20040142667A1 (en) 2003-01-21 2004-07-22 Lochhead Donald Laird Method of correcting distortion in a power amplifier
US7295819B2 (en) 2003-03-11 2007-11-13 Andrew Corporation Signal sample acquisition techniques
US7123890B2 (en) 2003-03-11 2006-10-17 Andrew Corporation Signal sample acquisition techniques
US6975222B2 (en) 2003-03-21 2005-12-13 Baldev Krishan Asset tracking apparatus and method
US6922102B2 (en) * 2003-03-28 2005-07-26 Andrew Corporation High efficiency amplifier
US7349490B2 (en) * 2003-04-16 2008-03-25 Powerwave Technologies, Inc. Additive digital predistortion system employing parallel path coordinate conversion
US7038539B2 (en) 2003-05-06 2006-05-02 Powerwave Technologies, Inc. RF amplifier employing active load linearization
US7251293B2 (en) 2003-06-27 2007-07-31 Andrew Corporation Digital pre-distortion for the linearization of power amplifiers with asymmetrical characteristics
JP2005020675A (ja) 2003-06-30 2005-01-20 Maruko & Co Ltd デジタル直交変換器
US7302278B2 (en) 2003-07-03 2007-11-27 Rotani, Inc. Method and apparatus for high throughput multiple radio sectorized wireless cell
US7068101B2 (en) 2003-07-03 2006-06-27 Icefyre Semiconductor Corporation Adaptive predistortion for a transmit system
JP4356384B2 (ja) 2003-07-09 2009-11-04 日本電気株式会社 非線形補償回路と送信装置並びに非線形補償方法
KR100546245B1 (ko) 2003-07-10 2006-01-26 단암전자통신주식회사 프리디스토션을 이용한 전력 증폭 장치, 그 방법 및 그장치를 포함하는 무선 통신 시스템
US7801038B2 (en) 2003-07-14 2010-09-21 Siemens Corporation Method and apparatus for providing a delay guarantee for a wireless network
US7259630B2 (en) * 2003-07-23 2007-08-21 Andrew Corporation Elimination of peak clipping and improved efficiency for RF power amplifiers with a predistorter
US7042287B2 (en) * 2003-07-23 2006-05-09 Northrop Grumman Corporation System and method for reducing dynamic range and improving linearity in an amplication system
CN100505588C (zh) 2003-07-26 2009-06-24 华为技术有限公司 一种光纤传输系统、光纤传输的实现方法及终端处理装置
US6963242B2 (en) * 2003-07-31 2005-11-08 Andrew Corporation Predistorter for phase modulated signals with low peak to average ratios
JP4093937B2 (ja) 2003-08-21 2008-06-04 富士通株式会社 光伝送システム
US20050143091A1 (en) 2003-09-02 2005-06-30 Yair Shapira Indoor location identification system
US7149482B2 (en) 2003-09-16 2006-12-12 Andrew Corporation Compensation of filters in radio transmitters
US7109792B2 (en) * 2003-09-17 2006-09-19 Andrew Corporation Table-based pre-distortion for amplifier systems
JP4394409B2 (ja) * 2003-09-25 2010-01-06 株式会社日立国際電気 プリディストーション方式歪補償機能付き増幅器
US7372918B2 (en) * 2003-09-30 2008-05-13 Infineon Technologies Ag Transmission device with adaptive digital predistortion, transceiver with transmission device, and method for operating a transmission device
SE0302596D0 (sv) 2003-09-30 2003-09-30 Ericsson Telefon Ab L M Improvments in or relating to base stations
US20100067906A1 (en) 2003-10-02 2010-03-18 Balluff Gmbh Bandwidth allocation and management system for cellular networks
US7023273B2 (en) 2003-10-06 2006-04-04 Andrew Corporation Architecture and implementation methods of digital predistortion circuitry
JP2005150932A (ja) 2003-11-12 2005-06-09 Hitachi Kokusai Electric Inc プリディスト−ション装置
KR20050052556A (ko) 2003-11-28 2005-06-03 삼성전자주식회사 하이브리드 결합기를 이용한 다중 경로 전력 증폭기
US7071777B2 (en) 2003-12-02 2006-07-04 Motorola, Inc. Digital memory-based predistortion technique
KR101058733B1 (ko) 2004-01-02 2011-08-22 삼성전자주식회사 전력 증폭기의 비선형 왜곡 특성을 보상하는 전치보상 장치
EP1553791B1 (en) * 2004-01-08 2007-06-13 Evolium S.A.S. Radio base station with multiple radio frequency heads
US20050157675A1 (en) 2004-01-16 2005-07-21 Feder Peretz M. Method and apparatus for cellular communication over data networks
US7366252B2 (en) 2004-01-21 2008-04-29 Powerwave Technologies, Inc. Wideband enhanced digital injection predistortion system and method
US8010073B2 (en) 2004-01-22 2011-08-30 Broadcom Corporation System and method for adjusting power amplifier output power in linear dB steps
US7469491B2 (en) * 2004-01-27 2008-12-30 Crestcom, Inc. Transmitter predistortion circuit and method therefor
JP4467319B2 (ja) 2004-01-29 2010-05-26 株式会社日立国際電気 プリディストータ
JP4255849B2 (ja) * 2004-01-29 2009-04-15 株式会社エヌ・ティ・ティ・ドコモ べき級数型ディジタルプリディストータ
CN100341292C (zh) 2004-02-02 2007-10-03 华为技术有限公司 一种分布式基站的组网方法
WO2005076495A1 (en) * 2004-02-09 2005-08-18 Sige Semiconductor Inc. Methods of enhancing power amplifier linearity
CN100542345C (zh) 2004-02-11 2009-09-16 三星电子株式会社 操作时分双工/虚拟频分双工分级蜂窝电信系统的方法
FI20040220A0 (fi) 2004-02-12 2004-02-12 Nokia Corp Etäradio-osien tunnistaminen viestintäjärjestelmässä
JP2005229268A (ja) 2004-02-12 2005-08-25 Renesas Technology Corp 高周波電力増幅回路および無線通信システム
US6998909B1 (en) * 2004-02-17 2006-02-14 Altera Corporation Method to compensate for memory effect in lookup table based digital predistorters
EP1566979A1 (de) 2004-02-23 2005-08-24 Siemens Aktiengesellschaft Mehrfache Verwendung einer standardisierten Schnittstelle in einer Vorrichtung
US7577211B2 (en) 2004-03-01 2009-08-18 Powerwave Technologies, Inc. Digital predistortion system and method for linearizing an RF power amplifier with nonlinear gain characteristics and memory effects
US7336725B2 (en) 2004-03-03 2008-02-26 Powerwave Technologies, Inc. Digital predistortion system and method for high efficiency transmitters
US7312750B2 (en) 2004-03-19 2007-12-25 Comware, Inc. Adaptive beam-forming system using hierarchical weight banks for antenna array in wireless communication system
JP4448955B2 (ja) 2004-03-29 2010-04-14 ユーティーシダカントンシュンユーシァンゴンシ マルチモード無線ネットワークにおけるリソース管理方法およびトラフィック誘導方法
JP4520204B2 (ja) * 2004-04-14 2010-08-04 三菱電機株式会社 高周波電力増幅器
JP2007534241A (ja) 2004-04-22 2007-11-22 ユーティー斯▲達▼康通▲訊▼有限公司 リソースを集中的に制御する分散無線システム
WO2005104580A1 (fr) 2004-04-23 2005-11-03 Utstarcom Telecom Co., Ltd. Procede et appareil de transmission de signal multi-antenne dans une bs rf sans fil longue distance
US7102442B2 (en) * 2004-04-28 2006-09-05 Sony Ericsson Mobile Communications Ab Wireless terminals, methods and computer program products with transmit power amplifier input power regulation
KR101126401B1 (ko) 2004-05-11 2012-03-29 삼성전자주식회사 전력 증폭기에 디지털 전치 왜곡 장치 및 방법
JP4417174B2 (ja) * 2004-05-19 2010-02-17 株式会社日立国際電気 プリディストータ
US7676804B2 (en) * 2004-05-20 2010-03-09 Caterpillar Inc. Systems and method for remotely modifying software on a work machine
US8346293B2 (en) 2004-06-14 2013-01-01 Panasonic Corporation Radio communication device supporting a plurality of communication schemes
CN100544459C (zh) 2004-07-13 2009-09-23 Ut斯达康通讯有限公司 远程射频单元与集中式基站的接口方法
WO2006005229A1 (fr) 2004-07-13 2006-01-19 Utstarcom Telecom Co., Ltd. Procede de transmission de paquets de signaux sans fil dans une station de base radio
US7113037B2 (en) * 2004-07-14 2006-09-26 Raytheon Company Performing remote power amplifier linearization
US7151405B2 (en) 2004-07-14 2006-12-19 Raytheon Company Estimating power amplifier non-linearity in accordance with memory depth
US20080031380A1 (en) 2004-08-30 2008-02-07 Shinichiro Takabayashi Peak Power Suppressing Apparatus and Peak Power Supressing Method
JP4214098B2 (ja) 2004-09-09 2009-01-28 株式会社ルネサステクノロジ シグマデルタ送信回路及びそれを用いた送受信機
US7463697B2 (en) 2004-09-28 2008-12-09 Intel Corporation Multicarrier transmitter and methods for generating multicarrier communication signals with power amplifier predistortion and linearization
EP1810534B1 (en) 2004-10-12 2015-06-17 Telefonaktiebolaget LM Ericsson (publ) Communication between a radio equipment control node and multiple remote radio equipment nodes
BRPI0419134B1 (pt) * 2004-10-25 2018-08-07 Telecom Italia S.P.A. Método de comunicações entre uma estação principal e nós de processamento, e, rede de comunicações
US7313415B2 (en) 2004-11-01 2007-12-25 Nextg Networks, Inc. Communications system and method
US7362776B2 (en) 2004-11-01 2008-04-22 Cisco Technology, Inc. Method for multicast load balancing in wireless LANs
CN1774094A (zh) 2004-11-08 2006-05-17 华为技术有限公司 一种无线基站系统及其发射和接收信息的方法
US8527003B2 (en) 2004-11-10 2013-09-03 Newlans, Inc. System and apparatus for high data rate wireless communications
US7433668B2 (en) 2004-12-23 2008-10-07 Lucent Technologies Inc. Controlling Q-factor of filters
US7104310B2 (en) * 2004-12-27 2006-09-12 Hunter Automated Machinery Corporation Mold making machine with separated safety work zones
CN100426897C (zh) 2005-01-12 2008-10-15 华为技术有限公司 分体式基站系统及其组网方法和基带单元
US7787854B2 (en) 2005-02-01 2010-08-31 Adc Telecommunications, Inc. Scalable distributed radio network
WO2006087864A1 (ja) * 2005-02-17 2006-08-24 Hitachi Kokusai Electric Inc. プリディストータ
JP4683468B2 (ja) 2005-03-22 2011-05-18 ルネサスエレクトロニクス株式会社 高周波電力増幅回路
US7193462B2 (en) 2005-03-22 2007-03-20 Powerwave Technologies, Inc. RF power amplifier system employing an analog predistortion module using zero crossings
DE102005013881A1 (de) 2005-03-24 2006-09-28 Infineon Technologies Ag Verfahren zur Signalverarbeitung und Sendeeinrichtung mit digitaler Vorverzerrung, insbesondere für den Mobilfunk
US7474891B2 (en) 2005-03-31 2009-01-06 Adc Telecommunications, Inc. Dynamic digital up and down converters
US7640019B2 (en) 2005-03-31 2009-12-29 Adc Telecommunications, Inc. Dynamic reallocation of bandwidth and modulation protocols
BRPI0520163B1 (pt) 2005-03-31 2018-11-27 Telecom Italia Spa método para controlar a operação de pelo menos uma estação rádio base em uma rede de rádio móvel, estação rádio base para uma rede de rádio móvel, e, sistema que compreende a respectiva estação rádio base
US7398106B2 (en) 2005-03-31 2008-07-08 Adc Telecommunications, Inc. Dynamic readjustment of power
BRPI0520164A2 (pt) 2005-03-31 2009-09-15 Telecom Italia Spa método para prover cobertura de rádio em uma rede de rádio móvel, rede de rádio móvel, e, produto de programa de computador
US7423988B2 (en) 2005-03-31 2008-09-09 Adc Telecommunications, Inc. Dynamic reconfiguration of resources through page headers
US7688792B2 (en) 2005-04-21 2010-03-30 Qualcomm Incorporated Method and apparatus for supporting wireless data services on a TE2 device using an IP-based interface
CN100576724C (zh) 2005-05-18 2009-12-30 株式会社Ntt都科摩 幂级数型前置补偿器及其控制方法
US7499682B2 (en) * 2005-05-24 2009-03-03 Skyworks Solutions, Inc. Dual voltage regulator for a supply voltage controlled power amplifier in a closed power control loop
US7603141B2 (en) 2005-06-02 2009-10-13 Qualcomm, Inc. Multi-antenna station with distributed antennas
JP2006340166A (ja) 2005-06-03 2006-12-14 Nippon Dengyo Kosaku Co Ltd 歪補償増幅器
JP4344367B2 (ja) 2005-06-06 2009-10-14 株式会社エヌ・ティ・ティ・ドコモ 多周波帯用べき級数型プリディストータ
US8112094B1 (en) 2005-06-09 2012-02-07 At&T Mobility Ii Llc Radio access layer management
US20070008939A1 (en) 2005-06-10 2007-01-11 Adc Telecommunications, Inc. Providing wireless coverage into substantially closed environments
JP4410158B2 (ja) 2005-06-24 2010-02-03 株式会社東芝 通信システム及びそれに用いられる親機中継装置
DE602005002259T2 (de) 2005-06-30 2008-05-21 Ntt Docomo Inc. Vorrichtung und Verfahren für verbesserte Weiterreichung in Maschennetzwerken
JP5301831B2 (ja) 2005-06-30 2013-09-25 富士通株式会社 歪補償回路を有する電力増幅器
GB0513583D0 (en) 2005-07-01 2005-08-10 Nokia Corp A mobile communications network with multiple radio units
CN1905729A (zh) 2005-07-29 2007-01-31 西门子(中国)有限公司 分布式天线系统中的无线通信资源配置方法
US20070058742A1 (en) 2005-09-09 2007-03-15 Demarco Anthony Distributed antenna system using signal precursors
US20070057737A1 (en) * 2005-09-14 2007-03-15 Freescale Semiconductor, Inc. Compensation for modulation distortion
JP4634902B2 (ja) 2005-09-30 2011-02-16 日本放送協会 送信装置及びプログラム
US7286507B1 (en) 2005-10-04 2007-10-23 Sprint Spectrum L.P. Method and system for dynamically routing between a radio access network and distributed antenna system remote antenna units
US7616610B2 (en) 2005-10-04 2009-11-10 Motorola, Inc. Scheduling in wireless communication systems
US20070075780A1 (en) * 2005-10-05 2007-04-05 Enver Krvavac Apparatus and method for adaptive biasing of a Doherty amplifier
CN1960231A (zh) 2005-10-31 2007-05-09 Ut斯达康通讯有限公司 Cpri链路多路复用传输方法及系统
US7301402B2 (en) 2005-11-17 2007-11-27 Freescale Semiconductor, Inc. Soft saturation detection for power amplifiers
US7496367B1 (en) 2005-11-22 2009-02-24 Nortel Networks Limited Method of multi-carrier traffic allocation for wireless communication system
US7831221B2 (en) 2005-12-13 2010-11-09 Andrew Llc Predistortion system and amplifier for addressing group delay modulation
US20070274279A1 (en) 2005-12-19 2007-11-29 Wood Steven A Distributed antenna system employing digital forward deployment of wireless transmit/receive locations
KR20070069731A (ko) 2005-12-28 2007-07-03 삼성전자주식회사 광대역 무선 통신 시스템의 기지국에서 디지털 장치와 원격알에프 장치간의 통신 장치 및 방법
US7813451B2 (en) 2006-01-11 2010-10-12 Mobileaccess Networks Ltd. Apparatus and method for frequency shifting of a wireless signal and systems using frequency shifting
JP2007195056A (ja) 2006-01-20 2007-08-02 Matsushita Electric Ind Co Ltd 歪み補償装置及び歪み補償方法
US7626591B2 (en) * 2006-01-24 2009-12-01 D & S Consultants, Inc. System and method for asynchronous continuous-level-of-detail texture mapping for large-scale terrain rendering
US8195103B2 (en) 2006-02-15 2012-06-05 Texas Instruments Incorporated Linearization of a transmit amplifier
JP2007235738A (ja) 2006-03-02 2007-09-13 Sumitomo Electric Ind Ltd 通信システム
US20070223614A1 (en) 2006-03-23 2007-09-27 Ravi Kuchibhotla Common time frequency radio resource in wireless communication systems
US7610046B2 (en) 2006-04-06 2009-10-27 Adc Telecommunications, Inc. System and method for enhancing the performance of wideband digital RF transport systems
US7599711B2 (en) 2006-04-12 2009-10-06 Adc Telecommunications, Inc. Systems and methods for analog transport of RF voice/data communications
GB2437586A (en) 2006-04-27 2007-10-31 Motorola Inc High speed downlink packet access communication in a cellular communication system
EP2022179A4 (en) 2006-04-28 2009-12-23 Dali Systems Co Ltd HIGH PERFORMANCE LINEARIZATION POWER AMPLIFIER FOR WIRELESS COMMUNICATION
US7826810B2 (en) 2006-05-08 2010-11-02 Harris Corporation Multiband radio with transmitter output power optimization
US20070264947A1 (en) 2006-05-10 2007-11-15 Dmitriy Rozenblit System and method for saturation detection and compensation in a polar transmitter
JP4839133B2 (ja) 2006-05-22 2011-12-21 株式会社日立製作所 ストレージ装置のデータ管理方法及び計算機システム
US7733978B2 (en) 2006-05-26 2010-06-08 Industrial Technology Research Institute Apparatus and method of dynamically adapting the LUT spacing for linearizing a power amplifier
JP4981494B2 (ja) 2006-05-30 2012-07-18 株式会社日立国際電気 無線通信システム及び張り出し局装置
US8477614B2 (en) 2006-06-30 2013-07-02 Centurylink Intellectual Property Llc System and method for routing calls if potential call paths are impaired or congested
US20080045254A1 (en) 2006-08-15 2008-02-21 Motorola, Inc. Method and Apparatus for Maximizing Resource Utilization of Base Stations in a Communication Network
US8064391B2 (en) 2006-08-22 2011-11-22 Embarq Holdings Company, Llc System and method for monitoring and optimizing network performance to a wireless device
US7848770B2 (en) 2006-08-29 2010-12-07 Lgc Wireless, Inc. Distributed antenna communications system and methods of implementing thereof
JP2008078702A (ja) 2006-09-19 2008-04-03 Fujitsu Ltd 増幅器故障検出装置
JP5312734B2 (ja) 2006-09-20 2013-10-09 富士通株式会社 移動通信端末
US9554284B2 (en) 2006-09-22 2017-01-24 Alvarion Ltd. Wireless over PON
CN101536465B (zh) 2006-09-27 2012-05-23 意大利电信股份公司 实现可配置的资源管理策略的设备和方法
US7778307B2 (en) 2006-10-04 2010-08-17 Motorola, Inc. Allocation of control channel for radio resource assignment in wireless communication systems
JP4791320B2 (ja) 2006-10-13 2011-10-12 富士通株式会社 コモン・パブリック・ラジオ・インタフェース(cpri)のベンダー特有領域を使った回線迂回方式
US7583677B1 (en) 2006-11-03 2009-09-01 Juniper Networks, Inc. Dynamic flow-based multi-path load balancing with quality of service assurances
EP1924109B1 (en) 2006-11-20 2013-11-06 Alcatel Lucent Method and system for wireless cellular indoor communications
JP2008135955A (ja) 2006-11-28 2008-06-12 Toshiba Corp Rofシステムおよび子局装置設置方法
FI20065783A0 (sv) 2006-12-08 2006-12-08 Nokia Corp Signalfördistorsion i radiosändare
US9026067B2 (en) 2007-04-23 2015-05-05 Dali Systems Co. Ltd. Remotely reconfigurable power amplifier system and method
CN102017553B (zh) 2006-12-26 2014-10-15 大力系统有限公司 用于多信道宽带通信系统中的基带预失真线性化的方法和系统
US8374271B2 (en) 2007-01-08 2013-02-12 Cisco Technology, Inc. Method and system for resizing a MIMO channel
US20080181182A1 (en) 2007-01-12 2008-07-31 Scott Carichner Digital radio head system and method
US8737454B2 (en) 2007-01-25 2014-05-27 Adc Telecommunications, Inc. Modular wireless communications platform
US8583100B2 (en) 2007-01-25 2013-11-12 Adc Telecommunications, Inc. Distributed remote base station system
CN101606315B (zh) 2007-01-26 2014-07-02 大力系统有限公司 功率放大器时间延迟不变的预失真方法和装置
US20090013317A1 (en) 2007-02-08 2009-01-08 Airnet Communications Corporation Software Management for Software Defined Radio in a Distributed Network
WO2008099383A2 (en) 2007-02-12 2008-08-21 Mobileaccess Networks Ltd. Mimo-adapted distributed antenna system
US20080240286A1 (en) 2007-03-26 2008-10-02 Innofidei, Inc. Signal transmission system, method and apparatus
US8274332B2 (en) 2007-04-23 2012-09-25 Dali Systems Co. Ltd. N-way Doherty distributed power amplifier with power tracking
KR101503548B1 (ko) 2007-04-23 2015-03-24 달리 시스템즈 씨오. 엘티디. 디지털 하이브리드 모드 전력 증폭기 시스템
JP5040998B2 (ja) 2007-05-31 2012-10-03 富士通株式会社 無線基地局装置および無線基地局装置内のリンク断救済方法
WO2008155764A2 (en) 2007-06-18 2008-12-24 Duolink Ltd. Wireless network architecture and method for base station utilization
US8010116B2 (en) 2007-06-26 2011-08-30 Lgc Wireless, Inc. Distributed antenna communications system
US8964532B2 (en) 2007-06-29 2015-02-24 Alcatel Lucent Wireless communication device including a standby radio
US7702300B1 (en) 2007-07-12 2010-04-20 Panasonic Corporation Envelope modulator saturation detection using a DC-DC converter
US20090019664A1 (en) 2007-07-20 2009-01-22 Kwin Abram Square bushing for exhaust valve
US8369809B2 (en) 2007-07-27 2013-02-05 Netlogic Microsystems, Inc. Crest factor reduction
JP2009038688A (ja) 2007-08-03 2009-02-19 Furuno Electric Co Ltd 無線装置
US8290088B2 (en) * 2007-08-07 2012-10-16 Research In Motion Limited Detecting the number of transmit antennas in a base station
WO2009023302A2 (en) 2007-08-14 2009-02-19 Rambus Inc. Communication using continuous-phase modulated signals
US7948897B2 (en) 2007-08-15 2011-05-24 Adc Telecommunications, Inc. Delay management for distributed communications networks
US20090060496A1 (en) 2007-08-31 2009-03-05 Liu David H Method and system for enabling diagnosing of faults in a passive optical network
US8010099B2 (en) 2007-09-04 2011-08-30 Alcatel Lucent Methods of reconfiguring sector coverage in in-building communications system
CN101394647B (zh) 2007-09-21 2013-10-02 电信科学技术研究院 一种实现小区组网的方法及系统
US8103267B2 (en) 2007-09-26 2012-01-24 Via Telecom, Inc. Femtocell base station with mobile station capability
EP2179506B1 (en) 2007-10-01 2011-01-26 ST Wireless SA Correlation-driven adaptation of frequency control for a rf receiver device
FI20075690A0 (fi) 2007-10-01 2007-10-01 Nokia Corp Signaalin esivääristäminen radiolähettimessä
US8478331B1 (en) 2007-10-23 2013-07-02 Clearwire Ip Holdings Llc Method and system for transmitting streaming media content to wireless subscriber stations
JP5252881B2 (ja) * 2007-11-02 2013-07-31 株式会社エヌ・ティ・ティ・ドコモ 移動通信システムで使用される基地局及び方法
WO2009067072A1 (en) 2007-11-21 2009-05-28 Telefonaktiebolaget L M Ericsson (Publ) A method and a radio base station in a telecommunications system
CN101453799B (zh) 2007-11-30 2010-05-19 京信通信系统(中国)有限公司 多载波数字选频射频拉远系统及其信号处理方法
CN201127027Y (zh) 2007-11-30 2008-10-01 京信通信系统(中国)有限公司 多载波数字选频射频拉远系统
US7598907B2 (en) 2007-12-06 2009-10-06 Kyocera Corporation System and method for WWAN/WLAN position estimation
EP2248255A4 (en) 2007-12-07 2014-05-28 Dali Systems Co Ltd DIGITAL PREDISTORSION RF DERIVED BASEBAND
CN101459913B (zh) 2007-12-12 2010-10-27 华为技术有限公司 无线通信系统、中心站、接入设备及通信方法
JP5017072B2 (ja) 2007-12-13 2012-09-05 キヤノン株式会社 画像処理装置、その制御方法及びプログラム
WO2009081376A2 (en) 2007-12-20 2009-07-02 Mobileaccess Networks Ltd. Extending outdoor location based services and applications into enclosed areas
US8855036B2 (en) 2007-12-21 2014-10-07 Powerwave Technologies S.A.R.L. Digital distributed antenna system
US8165100B2 (en) 2007-12-21 2012-04-24 Powerwave Technologies, Inc. Time division duplexed digital distributed antenna system
US9385804B2 (en) 2008-01-15 2016-07-05 Intel Deutschland Gmbh Transmission unit and a method for transmitting data
GB0800767D0 (en) 2008-01-16 2008-02-27 Nec Corp A method for controlling access to a mobile communications network
US8666428B2 (en) 2008-01-29 2014-03-04 Alcatel Lucent Method to support user location in in-structure coverage systems
ES2554541T3 (es) 2008-02-08 2015-12-21 Adc Telecommunications, Inc Una red móvil de empresa para suministrar un servicio de telefonía móvil (celular) inalámbrica utilizando un espectro de radiofrecuencia con licencia y una red de retorno de protocolo de internet
KR20090088083A (ko) 2008-02-14 2009-08-19 삼성전자주식회사 분산 안테나 시스템에서 사용자 선택을 위한 장치 및 방법
FI20085158A0 (fi) 2008-02-21 2008-02-21 Nokia Corp Laite ja menetelmä
CN101521893B (zh) 2008-02-25 2010-12-01 京信通信系统(中国)有限公司 宽带数字选频射频拉远系统及其信号处理方法
US8204544B2 (en) 2008-03-27 2012-06-19 Rockstar Bidco, LP Agile remote radio head
US8428077B2 (en) 2008-03-31 2013-04-23 Qualcomm Incorporated Methods and apparatus for dynamic load balancing with E-AICH
US9049687B2 (en) 2008-05-05 2015-06-02 Industrial Technology Research Institute System and method for providing multicast and/or broadcast services
US20090286484A1 (en) 2008-05-19 2009-11-19 Lgc Wireless, Inc. Method and system for performing onsite maintenance of wireless communication systems
US8005152B2 (en) 2008-05-21 2011-08-23 Samplify Systems, Inc. Compression of baseband signals in base transceiver systems
JP5090258B2 (ja) 2008-06-05 2012-12-05 日本電信電話株式会社 無線アクセスシステムおよび端末局装置ならびに無線アクセス方法
TWI372531B (en) 2008-06-10 2012-09-11 Ind Tech Res Inst Wireless network, access point, and load balancing method thereof
US8208414B2 (en) 2008-06-24 2012-06-26 Lgc Wireless, Inc. System and method for configurable time-division duplex interface
KR101511786B1 (ko) * 2008-06-30 2015-04-14 엘지전자 주식회사 주파수 분할 이중 중계국을 포함하는 무선통신 시스템 및 이 무선통신 시스템에서의 무선자원의 이용 방법
EP2294860B1 (en) * 2008-07-03 2017-04-19 Telefonaktiebolaget LM Ericsson (publ) A method and apparatus for supporting fast carrier reselection
CN101621806B (zh) 2008-07-04 2011-09-21 京信通信系统(中国)有限公司 应用于gsm网络的智能化载波调度方法
KR100969741B1 (ko) 2008-07-11 2010-07-13 엘지노텔 주식회사 환형 혼성 성형망을 제공하기 위한 광통신 시스템
US7855977B2 (en) 2008-08-01 2010-12-21 At&T Mobility Ii Llc Alarming in a femto cell network
CN201307942Y (zh) 2008-09-17 2009-09-09 京信通信系统(中国)有限公司 射频拉远系统实现覆盖的无线区域中心
US8229416B2 (en) 2008-09-23 2012-07-24 Ixia Methods, systems, and computer readable media for stress testing mobile network equipment using a common public radio interface (CPRI)
US20100087227A1 (en) 2008-10-02 2010-04-08 Alvarion Ltd. Wireless base station design
US8565193B2 (en) 2008-10-16 2013-10-22 Elektrobit Wireless Communications Oy Beam forming method, apparatus and system
US9826409B2 (en) 2008-10-24 2017-11-21 Qualcomm Incorporated Adaptive semi-static interference avoidance in cellular networks
KR101481421B1 (ko) 2008-11-03 2015-01-21 삼성전자주식회사 이동 통신 시스템에서 단말의 화이트 리스트 관리 방법 및 장치
US8385483B2 (en) 2008-11-11 2013-02-26 Isco International, Llc Self-adaptive digital RF bandpass and bandstop filter architecture
TW201021473A (en) 2008-11-21 2010-06-01 Inventec Appliances Corp A master-slave system for mobile communications and a domain login method therefor
US20100128676A1 (en) 2008-11-24 2010-05-27 Dong Wu Carrier Channel Distribution System
CN101754229B (zh) 2008-11-28 2012-10-24 京信通信系统(中国)有限公司 载波信道动态调度的通信覆盖系统
CN101754431B (zh) 2008-12-01 2012-07-04 中国移动通信集团天津有限公司 无线专用网络系统、设备及信号传输和切换方法
CN101453699B (zh) 2008-12-30 2012-04-25 华为技术有限公司 一种广告播放方法和用户终端
JP2012515507A (ja) 2009-01-13 2012-07-05 エーデーシー・テレコミュニケーションズ・インコーポレーテッド 分散アンテナシステムにおける向上したデジタルrf送信のためのシステムおよび方法
US8346278B2 (en) 2009-01-13 2013-01-01 Adc Telecommunications, Inc. Systems and methods for mobile phone location with digital distributed antenna systems
US8213401B2 (en) 2009-01-13 2012-07-03 Adc Telecommunications, Inc. Systems and methods for IP communication over a distributed antenna system transport
JP5216604B2 (ja) 2009-01-19 2013-06-19 株式会社日立国際電気 無線装置
US8467355B2 (en) 2009-01-22 2013-06-18 Belair Networks Inc. System and method for providing wireless local area networks as a service
KR101562518B1 (ko) 2009-01-22 2015-10-23 삼성전자주식회사 통신 시스템 및 그의 펨토 기지국 연결 변경 방법
JP5445866B2 (ja) 2009-01-30 2014-03-19 株式会社日立製作所 無線通信システム及び通信制御方法
US8098572B2 (en) 2009-02-03 2012-01-17 Google Inc. Interface monitoring for link aggregation
US20130153298A1 (en) 2009-02-19 2013-06-20 Interdigital Patent Holdings, Inc. Method and apparatus for enhancing cell-edge user performance and signaling radio link failure conditions via downlink cooperative component carriers
US7826369B2 (en) 2009-02-20 2010-11-02 Cisco Technology, Inc. Subsets of the forward information base (FIB) distributed among line cards in a switching device
KR101770822B1 (ko) 2009-02-22 2017-08-24 엘지전자 주식회사 무선 통신 시스템에서 인터 워킹 신호 전송 방법 및 장치
EP2590343B1 (en) 2009-03-12 2017-12-27 Alcatel Lucent Antenna synchronization for coherent network mimo
US8472965B2 (en) * 2009-03-17 2013-06-25 Qualcomm Incorporated Mobility in multi-carrier high speed packet access
US8606321B2 (en) 2009-04-09 2013-12-10 Alcatel Lucent High-selectivity low noise receiver front end
US8422885B2 (en) 2009-04-16 2013-04-16 Trex Enterprises Corp Bandwidth allocation and management system for cellular networks
US9432991B2 (en) 2009-04-21 2016-08-30 Qualcomm Incorporated Enabling support for transparent relays in wireless communication
US9154352B2 (en) 2009-04-21 2015-10-06 Qualcomm Incorporated Pre-communication for relay base stations in wireless communication
US8849190B2 (en) 2009-04-21 2014-09-30 Andrew Llc Radio communication systems with integrated location-based measurements for diagnostics and performance optimization
US8289910B2 (en) 2009-04-24 2012-10-16 Kathrein-Werke Kg Device for receiving and transmitting mobile telephony signals with multiple transmit-receive branches
EP2430531B1 (en) 2009-04-24 2019-12-04 Dali Systems Co. Ltd. Remotely reconfigurable power amplifier system and method
US8346091B2 (en) 2009-04-29 2013-01-01 Andrew Llc Distributed antenna system for wireless network systems
ITMO20090135A1 (it) 2009-05-19 2010-11-20 Teko Telecom S P A Sistema e metodo per la distribuzione di segnali a radiofrequenza
US8812347B2 (en) 2009-05-21 2014-08-19 At&T Mobility Ii Llc Aggregating and capturing subscriber traffic
EP3595393B1 (en) 2009-05-22 2022-10-26 Huawei Technologies Co., Ltd. Multi-slot scheduling methods, apparatuses and non-transitory computer-readable media
US8588614B2 (en) 2009-05-22 2013-11-19 Extenet Systems, Inc. Flexible distributed antenna system
US20100304773A1 (en) 2009-05-27 2010-12-02 Ramprashad Sean A Method for selective antenna activation and per antenna or antenna group power assignments in cooperative signaling wireless mimo systems
US8139492B1 (en) 2009-06-09 2012-03-20 Juniper Networks, Inc. Local forwarding bias in a multi-chassis router
US8811925B2 (en) 2009-06-10 2014-08-19 Clearwire Ip Holdings Llc System and method for providing external receiver gain compensation when using an antenna with a pre-amplifier
US8842649B2 (en) 2009-06-19 2014-09-23 China Academy Of Telecommunications Technology Remote radio data transmission over Ethernet
US8634313B2 (en) * 2009-06-19 2014-01-21 Qualcomm Incorporated Method and apparatus that facilitates a timing alignment in a multicarrier system
TWI372882B (en) 2009-06-23 2012-09-21 Univ Nat Chiao Tung The gps tracking system
US20110069657A1 (en) 2009-09-09 2011-03-24 Qualcomm Incorporated System and method for the simultaneous transmission and reception of flo and flo-ev data over a multi-frequency network
US8451735B2 (en) 2009-09-28 2013-05-28 Symbol Technologies, Inc. Systems and methods for dynamic load balancing in a wireless network
CN102044736B (zh) 2009-10-14 2015-05-20 中兴通讯股份有限公司 射频拉远单元
US20110103309A1 (en) 2009-10-30 2011-05-05 Interdigital Patent Holdings, Inc. Method and apparatus for concurrently processing multiple radio carriers
US8804870B2 (en) 2009-12-21 2014-08-12 Dali Systems Co. Ltd. Modulation agnostic digital hybrid mode power amplifier system and method
US8542768B2 (en) 2009-12-21 2013-09-24 Dali Systems Co. Ltd. High efficiency, remotely reconfigurable remote radio head unit system and method for wireless communications
US8351877B2 (en) 2010-12-21 2013-01-08 Dali Systems Co. Ltfd. Multi-band wideband power amplifier digital predistorition system and method
US8320866B2 (en) 2010-02-11 2012-11-27 Mediatek Singapore Pte. Ltd. Integrated circuits, communication units and methods of cancellation of intermodulation distortion
US20110223958A1 (en) 2010-03-10 2011-09-15 Fujitsu Limited System and Method for Implementing Power Distribution
US8467823B2 (en) 2010-03-24 2013-06-18 Fujitsu Limited Method and system for CPRI cascading in distributed radio head architectures
US8681917B2 (en) 2010-03-31 2014-03-25 Andrew Llc Synchronous transfer of streaming data in a distributed antenna system
US8935543B2 (en) 2010-04-02 2015-01-13 Andrew Llc Method and apparatus for distributing power over communication cabling
US8559485B2 (en) 2010-04-08 2013-10-15 Andrew Llc Autoregressive signal processing for repeater echo cancellation
US8346160B2 (en) 2010-05-12 2013-01-01 Andrew Llc System and method for detecting and measuring uplink traffic in signal repeating systems
US9125068B2 (en) 2010-06-04 2015-09-01 Ixia Methods, systems, and computer readable media for simulating realistic movement of user equipment in a long term evolution (LTE) network
US20110302390A1 (en) 2010-06-05 2011-12-08 Greg Copeland SYSTEMS AND METHODS FOR PROCESSING COMMUNICATIONS SIGNALS fUSING PARALLEL PROCESSING
EP3481114B1 (en) 2010-06-09 2022-11-23 CommScope Technologies LLC Uplink noise minimization
US20110310881A1 (en) 2010-06-17 2011-12-22 Peter Kenington Remote radio head
US8774109B2 (en) 2010-06-17 2014-07-08 Kathrein-Werke Kg Mobile communications network with distributed processing resources
US8630211B2 (en) 2010-06-30 2014-01-14 Qualcomm Incorporated Hybrid radio architecture for repeaters using RF cancellation reference
US20140126914A1 (en) 2010-07-09 2014-05-08 Corning Cable Systems Llc Optical fiber-based distributed radio frequency (rf) antenna systems supporting multiple-input, multiple-output (mimo) configurations, and related components and methods
US8570914B2 (en) 2010-08-09 2013-10-29 Corning Cable Systems Llc Apparatuses, systems, and methods for determining location of a mobile device(s) in a distributed antenna system(s)
WO2012024349A1 (en) 2010-08-17 2012-02-23 Dali Systems Co. Ltd. Daisy-chained ring of remote units for a distributed antenna system
KR20180026793A (ko) 2010-08-17 2018-03-13 달리 시스템즈 씨오. 엘티디. 분산 안테나 시스템을 위한 뉴트럴 호스트 아키텍처
WO2012024345A2 (en) 2010-08-17 2012-02-23 Dali Systems Co. Ltd. Remotely reconfigurable distributed antenna system and methods
US8649388B2 (en) 2010-09-02 2014-02-11 Integrated Device Technology, Inc. Transmission of multiprotocol data in a distributed antenna system
KR101829517B1 (ko) 2010-09-14 2018-02-14 달리 시스템즈 씨오. 엘티디. 원격으로 재구성가능한 분산 안테나 시스템 및 방법
US8532242B2 (en) 2010-10-27 2013-09-10 Adc Telecommunications, Inc. Distributed antenna system with combination of both all digital transport and hybrid digital/analog transport
KR102250559B1 (ko) 2011-02-07 2021-05-11 달리 시스템즈 씨오. 엘티디. 분산 안테나 시스템을 위한 리모트 유닛의 데이지 체인형 링
US9439242B2 (en) 2012-08-13 2016-09-06 Dali Systems Co., Ltd. Time synchronized routing in a distributed antenna system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6054896A (en) * 1998-12-17 2000-04-25 Datum Telegraphic Inc. Controller and associated methods for a linc linear power amplifier

Also Published As

Publication number Publication date
JP5236661B2 (ja) 2013-07-17
US20150092830A1 (en) 2015-04-02
US20200092787A1 (en) 2020-03-19
US20130315291A1 (en) 2013-11-28
EP2106648A4 (en) 2014-03-26
US20190110239A1 (en) 2019-04-11
US9419837B2 (en) 2016-08-16
WO2008078195A3 (en) 2011-03-17
US20160269210A1 (en) 2016-09-15
WO2008078195A2 (en) 2008-07-03
US20140313884A1 (en) 2014-10-23
KR20100014339A (ko) 2010-02-10
EP2106648A2 (en) 2009-10-07
US8509347B2 (en) 2013-08-13
EP3416340A1 (en) 2018-12-19
US9246731B2 (en) 2016-01-26
US20170055198A1 (en) 2017-02-23
CN104202279A (zh) 2014-12-10
KR20140091616A (ko) 2014-07-21
US9913194B2 (en) 2018-03-06
US11006343B2 (en) 2021-05-11
US20120039254A1 (en) 2012-02-16
US9137078B2 (en) 2015-09-15
US20220007263A1 (en) 2022-01-06
US8149950B2 (en) 2012-04-03
US20200169937A1 (en) 2020-05-28
US20120147993A1 (en) 2012-06-14
US10334499B2 (en) 2019-06-25
US8737300B2 (en) 2014-05-27
US11129076B2 (en) 2021-09-21
US10080178B2 (en) 2018-09-18
EP2106648B1 (en) 2018-08-08
US11818642B2 (en) 2023-11-14
US20160014782A1 (en) 2016-01-14
EP3790244A1 (en) 2021-03-10
HK1205382A1 (zh) 2015-12-11
CN102017553A (zh) 2011-04-13
US8855234B2 (en) 2014-10-07
US20210329527A1 (en) 2021-10-21
US9148324B2 (en) 2015-09-29
US20080152037A1 (en) 2008-06-26
JP2010518660A (ja) 2010-05-27
US20230370937A1 (en) 2023-11-16
EP3416340B1 (en) 2020-10-21
US20130272202A1 (en) 2013-10-17
US20180279197A1 (en) 2018-09-27

Similar Documents

Publication Publication Date Title
CN102017553B (zh) 用于多信道宽带通信系统中的基带预失真线性化的方法和系统
US8787494B2 (en) Modeling digital predistorter
CN101156159B (zh) 用于高效率发射机的数字预失真系统和方法
CN101040502B (zh) 宽带增强型数字注射预失真系统和方法
JP4835241B2 (ja) ディジタルプリディストーション送信機
US6956433B2 (en) Polynomial predistorter using complex vector multiplication
EP2837093B1 (en) Digital predistorter (dpd) structure based on dynamic deviation reduction (ddr)-based volterra series
Kim et al. Piecewise pre-equalized linearization of the wireless transmitter with a Doherty amplifier
US8432220B2 (en) Linearization device for a power amplifier
CN100452644C (zh) 实现记忆型功率放大器线性化的方法及其基带预失真装置
CN107786174B (zh) 用于预失真的电路和方法
Ding et al. Time-domain adaptive predistortion for nonlinear amplifiers
Ding et al. Adaptive Linearization for Power Amplifier in OFDM Systems
Aslan Adaptive digital predistortion for power amplifier linearization
Peng et al. Training Sample Acquisition Strategy Based Digital Pre-distortion
Pehlivan Aslan Adaptive digital predistortion for power amplifier linearization

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant