DE102009008321A1 - Method for deciding on parallel use of common communication channel of wireless local area network for e.g. car-to-car application, involves transmitting data from subscriber to another subscriber via channel, when criterion is fulfilled - Google Patents

Abstract

The method involves determining transmission output of a transmit-compliant communications subscriber (C). A criterion is evaluated, where estimated received power of data (F) at a receiving communication subscriber (A) ensures qualitatively adequate communication of the receiving communication subscriber with an associated transmitting communication subscriber (B), when the criterion is fulfilled. The data is transmitted from the transmit-compliant communication subscriber to an associated communication subscriber (D) via a common communication channel (E), when the criterion is fulfilled. An independent claim is also included for a communication subscriber comprising a transmitting and receiving antenna.

Description

Wireless networks, In particular WLAN wireless networks, serve the wireless communication between several communication participants. Wireless networks are known, the transmission of Serving data in Car2Car or general Car2X applications.

One Main problem with the use of wireless networks, in particular of Wi-Fi wireless networks, in the communication between at least 4 communication participants, In particular, between motor vehicles, is that in an existing Communication between two communication participants via one Communication channel another, willing to send communication participants, the over would like to send the same communication channel, an assignment of the communication channel determines and waits until the communication between the already sending communication participants is completed. This results Waiting times for the send-willing communication participant, the time duration until to begin the data transfer extend. This is also known as the exposed node problem.

Of the The invention is therefore based on the technical problem of a method for the parallel use of a communication channel in a radio network, in particular a WLAN radio network, with at least 4 participants, in particular motor vehicles, as well as a for the Procedure to create suitable participants, who will wait for the send Shorten communication subscriber and thus to an improved data transmission in the radio network to lead.

The solution the technical problem arises from the objects with the features of the claims 1 and 16. Further advantageous embodiments of the invention result from the dependent claims.

• a) Bestimmung der Empfangsleistung (PRab) der von dem bereits sendenden Kommunikationsteilnehmer übermittelten Daten an dem bereits über den Kommunikationskanal empfangenden Kommunikationsteilnehmer,
• b) Bestimmung einer Sendeleistung (PTc) des sendewilligen Kommunikationsteilnehmers, die dem zugeordneten Kommunikationsteilnehmer einen qualitativ ausreichenden Empfang der zu übermittelnden Daten ermöglicht,
• c) Festlegung einer Sendeleistung (PTc) des sendewilligen Kommunikationsteilnehmers,
• d) Bestimmung der voraussichtlichen Empfangsleistung (PRac) der von dem sendewilligen Kommunikationsteilnehmer zu sendenden Daten an mindestens einem bereits über den Kommunikationskanal empfangenden Kommunikationsteilnehmer gemäß der in c) eingestellten Sendeleistung (PTc) und unter Berücksichtigung der relativen Lage des bereits empfangenden Kommunikationsteilnehmer zu dem sendewilligen Kommunikationsteilnehmer und
• e) Auswertung mindestens eines Kriteriums, bei dessen Erfüllung die voraussichtliche Empfangsleistung (PRac) der von dem sendewilligen Kommunikationsteilnehmer zu sendenden Daten an mindestens einem bereits über den Kommunikationskanal empfangenden Kommunikationsteilnehmer eine qualitativ ausreichende Kommunikation des bereits empfangenden Kommunikationsteilnehmers mit dem zugeordneten, bereits sendenden Kommunikationsteilnehmer gewährleistet.

Here decides a willing to send communication participants a radio network, which consists of at least 4 communication participants, at least two communication participants, consisting of at least one transmitting communication participants and at least one associated receiving communication participants, already transmit data via a communication channel that would like to start a communication to at least one associated communication participants and has means for determining the relative position between at least one and at least the already receiving communication subscriber, via the parallel use of a common communication channel by means of the following method steps:

• a) determination of the received power (PRab) of the data transmitted by the already transmitting communication subscriber at the communication subscriber already receiving via the communication channel,
• b) determining a transmission power (PTc) of the communication subscriber wishing to transmit, which enables the assigned communication subscriber to receive a sufficient amount of reception of the data to be transmitted,
• c) determination of a transmission power (PTc) of the communication subscriber wishing to send,
• d) Determining the anticipated reception power (PRac) of the data to be sent by the transmitting communication subscriber to at least one already received via the communication channel communication participant according to the set in c) transmission power (PTc) and taking into account the relative position of the already receiving communication participants to the sendwilligen communication participants and
• e) Evaluation of at least one criterion, the fulfillment of which presupposes the expected receiving power (PRac) of the data to be sent by the transmitting communication at least one already receiving via the communication channel communication quality adequate communication of the already receiving communication subscriber with the associated, already sending communication participants guaranteed.

The Sending data from the willing party to the communication assigned communication subscriber via the communication channel can take place if the criterion according to method step e) is fulfilled. This will allow that, at fulfillment of the criterion according to method step e), the time until the beginning of data transmission by the willing to send Communication participants shortened and improved data transmission enabled in wireless networks becomes.

Preferably, the received power (PRab) of the already receiving communication subscriber in step a) is determined by taking into account the relative position of the already communicating over the communication channel communication participants and determined by the sendewilligen communication subscriber transmit power (PTb) of the already transmitting communication subscriber via a model-based power calculation, the at least one parameter of the group transmission power (PTb), gain transmission antenna (GTAb), gain reception antenna (GRAa), propagation loss in free space (LBab), propagation loss due to weather (LUab) and other radio-related parameters such as the impact of the environment or the spatial Orientation of Communication participants to each other. This avoids that the determination of the received power (PRab) causes the transmission of further data, in particular the notification of the received power (PRab) by the receiving communication subscriber himself, via the radio network. The transmission of the data can be done for example via a control channel.

Further Preferably, the determination of the transmission power (PTc) of the sendewilligen communication subscriber in step b) under consideration the relative location of the communication subscriber wishing to transmit and the assigned, receiving communication subscriber via a Model-based performance calculation, the at least one parameter the group receive power (PRdc), gain transmit antenna (GTAc), Gain receive antenna (GRAd), propagation loss in free space (LBcd), propagation loss due to weather (LUcd) and other radio-related Contains parameters. This has the advantage that the transmit power (PTc) of the sendewilligen Communication participant to the assigned, receiving communication participants as the at least necessary transmission power is determined, the one high-quality reception of messages to be transmitted allows.

In a further preferred embodiment the determination of the transmit power (PTc) of the party wishing to transmit is carried out Communication subscriber in step c) via a constant transmission power setpoint, if the constant transmit power setpoint is greater than or equal to the in Step b) is certain transmission power. This makes it possible that the transmission power (PTc) of the send-willing communication subscriber does not have to be variably adjustable.

In an alternative embodiment the determination of the transmit power (PTc) of the party wishing to transmit is carried out Communication participant in step c) than those under step b) certain transmission power. Advantageous in this embodiment the determination of the transmission power (PTc) to the at least necessary transmission power, in order to receive a satisfactory level of reception To enable messages thereby minimizing the power required to send data. It can be provided that the specific transmission power to an absolute or percentage value is increased to a sufficient Receiving power to the send-willing communication participants to ensure assigned, receiving communication participants.

In a further embodiment the expected receiving power (PRac) is the one of the send Communication participants to send data to at least one already over the Communication channel receiving communication participants in step d) taking into account the relative position of the already over to the communication channel receiving communication subscriber the send-willing communication participant and the in step c) set transmission power (PTc) of the willing to send communication subscriber via a Model-based performance calculation determines that at least one Parameters of the group transmit power (PTc), gain transmit antenna (GTAc), Gain receiving antenna (GRAa), propagation loss in free space (LBac), propagation loss due to weather (LUac) and other radio-related Contains parameters. This allows advantageous the quantitative determination of the reception interference power by a taking place Data collision or overlay at the already receiving communication subscriber.

Further Preferably, there is the evaluation of a criterion in step e), at whose fulfillment the anticipated receiving power (PRac) of the person wishing to send Communication participants to send data to at least one already over the communication channel receiving communication participants a high-quality communication of the already receiving communication subscriber with the associated, already sending, communication participant ensures, from the calculation the signal to noise ratio (SigDifa) for at least one, already on the Communication channel receiving, communication participants and the Comparison with a general and / or subscriber-specific threshold. The advantage here is that by a data overlay resulting reception interference performance in a relationship is set to signal reception power. Furthermore, it is advantageous the evaluation with a threshold value method, wherein the threshold value for all Communication participants can be uniform, for example to simplified change the threshold for leads all participants, or wherein the threshold for different communication participants are chosen differently, for example, different reception sensitivities of different Communication participants to consider.

In a further preferred embodiment, the relative position determination of the communication participants takes place via mutual communication of the absolute position of the communication participants. The mutual communication of the absolute position can take place, for example, via a control channel and / or via so-called heartbeats and / or beacons. In a further preferred embodiment, the absolute position determination takes place via a satellite-based device belonging to each communication station Positioning. Other methods for absolute position determination can be used alternatively or cumulatively. Furthermore, it is possible to take into account the direction of movement and / or speed of the communication participants to each other by means of further sensor data.

Further Preferably, the method steps a) to f) with information about the temporal duration of the channel use of the already existing communication over the Communication channel linked. This advantageously allows estimate the duration of the existing communication.

In a preferred embodiment is the time duration of the channel use of the already existing Communication as information in the sent by the already sending communication participants Data integrated. The advantage here is the determination of the duration without additional Request to the already sending communication participant.

In an alternative embodiment is the time duration of the channel use of the already existing Communication from the data size of the data sent to the already sending communication user calculated. The advantage here is the determination of the duration without additional request at the already sending communication participant and without integration the information about the temporal duration of the channel use in that of the already sending Communication partner sent data.

In a further embodiment after step d) a determination of the received power (PRdb) that of at least one already transmitting communication subscriber data sent to the send to the willing communication partner assigned communication participants and after step e) the evaluation at least one criterion, at the fulfillment of which the reception power (PRdb) of the sent by the already sending communication subscriber Data on the communication participant belonging to the send-willing communication participant a qualitatively sufficient communication with the sendewilligen Communication participant ensured. A transmission the data to be sent by the willing to send communication participants occurs only if the criterion of step e) and the criterion at its fulfillment the received power (PRdb) of the already transmitting communication subscriber data sent to the send to the willing communication partner belonging communication partner a qualitatively sufficient communication with the sendewilligen Ensures communication Fulfills are. This advantageously ensures that a qualitative sufficient reception of the send-willing communication partner data to be sent to the assigned, receiving communication subscriber despite the communication already taking place.

In a further preferred embodiment the determination of the received power (PRdb) of at least a data already sent to a sending communication user the communication partner assigned to the send-willing communication participant consideration the relative position of the already over the communication channel sending communication subscriber and the to the send-willing communication participant belonging communication participants and the determined by the send-willing communication participants Transmission power (PTb) of the already transmitting communication subscriber via a Model-based performance calculation, the at least one parameter the group transmit power (PTb), gain transmit antenna (GTAb), profit Receiving antenna (GRAd), propagation loss in free space (LBbd), Propagation loss due to weather (LUbd) and other radio-related Contains parameters. This will enable that a reception interference performance by a successful data collision at the party willing to send communication assigned, receiving communication participants quantitatively can be determined.

In a further preferred embodiment there is the evaluation of at least one criterion, in the fulfillment of which Receive power (PRdb) of the already transmitting communication subscriber data sent to the send to the willing communication partner associated communication participants a sufficient quality Ensuring communication with the willing party to send communications from the calculation of the signal to noise ratio (SigDifd) for the the communication user who is willing to send the communication and the comparison with a general and / or participant-specific Threshold.

To carry out the method, at least one communication user in a radio network comprises at least one transmitting and receiving antenna, at least one transmitting and receiving unit and at least one evaluation and control unit, wherein the evaluation and control unit is equipped with first means by which the received power (PRab ) can be determined by the already transmitting communication subscriber data transmitted to the already receiving via the communication channel communication participants. Furthermore, the evaluation and Control unit equipped with means by which a transmission power (PTC) of the transmitting willing communication subscriber can be determined. Third, the evaluation and control unit is equipped with means by means of which a transmission power (PTc) of the transmitting-willing communication subscriber can be set. Fourth, the evaluation and control unit is equipped with means by which a relative position between at least the send-willing communication participants and the already received via the communication channel communication participants can be determined. In addition, the evaluation and control unit is equipped with fifth means by which an expected reception power (PRac) of the data to be sent by the transmitting communication subscriber to at least one already over the communication channel receiving communication participants according to a set transmit power (PTc) and taking into account the relative Location of the already receiving communication participants can be determined to the sendwilligen communication participants. Sixth, the evaluation and control unit is equipped with means by which a criterion, the fulfillment of the expected reception power (PRac) of the data to be sent by the transmitting communication participants on at least one already received via the communication channel communication participants a qualitatively sufficient communication already received Communication subscriber with the associated, already sending communication participants guaranteed, can be evaluated. Furthermore, the evaluation and control unit is equipped with seventh means by which the data to be sent by the sendwilligen communication participant can be generated. Eighth, the evaluation and control unit is equipped with means by which the transmitting unit can be activated and controlled.

Regarding further advantageous embodiments of the communication participants Reference is made to the preceding statements on the method claims taken.

The Invention will be described below with reference to a preferred embodiment explained in more detail. The Figures show:

1 four communication participants of a radio network with a communication channel and transmitted data and

2 a schematic block diagram of the units of a communication subscriber.

In 1 four communication subscribers A, B, C and D of a radio network are shown. The communication subscribers can be, for example, vehicles that communicate via a WLAN network. Each of the communication subscribers can bidirectionally exchange data with at least one other communication subscriber via a communication channel E. The data may include, for example, status information (intact or defective) of a vehicle or traffic information (flowing or halting). The exchange can take place, for example, via standard methods of WLAN communication. The communication participants can act both as sender and receiver. Im in 1 illustrated scenario transmit two associated communication participants A and B via a communication channel E data F. In this case, the data F are sent from a communication participant B and received by the associated communication participant A.

Of the Communication Participant C would like to join already successful data transmission between the communication participants A and B data assigned to a C. Communication participant D via send the same communication channel E in parallel. In communication via wireless networks will be this situation, for example, by the so-called Exposed Node Problem described, wherein the communication participant C the so-called Exposed Node represents.

Even though the scenario an already existing communication over the Communication channel E between the communication participants A and B and a send-willing communication participant C describes Of course, the same scenario can be done with different communication station configurations getting produced.

In 2 the block diagram of a communication subscriber C according to the invention is shown, which is exemplary for all other communication participants A, B, D. The communication subscriber C has a receiving unit 1 with a receiving antenna 4 for receiving data transmitted via radio networks and via a transmitting unit 3 with a transmitting antenna 5 for sending data via wireless networks. It can via the receiving unit 1 and receiving antenna 4 not only communication-specific data, but also data containing the absolute position of at least one other communication subscriber can be received. About the transmitting unit 3 and transmitting antenna 5 Not only communication-specific data but also data for communication of the absolute position of the communication subscriber C can be sent.

Furthermore, the communication subscriber C has a satellite-based position receive unit 6 with a receiving antenna 7 , which is used to determine the absolute spatial position of the communication subscriber C. Preferably, the satellite-based position receiving unit 6 executed as a GPS receiver.

Furthermore, the communication subscriber C has an evaluation and control unit 2 connected to the receiving unit 1 , the transmitting unit 3 and the position determination unit 6 is connected by data technology. For example, known communication methods and bus systems such as the CAN bus can be used here. The evaluation and control unit 2 includes the following means:
First means for determining the received power (PRab) of the data transmitted by the already transmitting communication subscriber B to the data already received via the communication channel communication participant A. This means is preferably supported by a model-based power calculation. The calculation takes into account, for example, the parameters transmission power of the communication subscriber B (PTb), gain of the transmission antenna of the communication subscriber B (GTAb), gain receiving antenna of the communication subscriber A (GRAa), propagation loss in free space between the communication subscribers A and B (LBab) and propagation loss Weather between the communication participants A and B (LUab). The quantitative determination of the parameters taken into account preferably takes place via parameter quantities that are available a priori or are communicated to the subscriber C willing to transmit via a control channel. Further possibilities for the quantitative determination of the parameters are the use of suitable measuring methods and / or the use of model-based parameter calculation methods. For example, the transmission power of the already transmitting communication subscriber B (PTb) is determined as the sum of those of the receiving unit 1 the communication subscriber C measured received power (PRcb) of the data sent from the already transmitting communication subscriber B data on the communication subscriber C and, calculated using a parameter model, propagation loss between the communication participants B and C (LBbc). The parameter models can take into account the relative spatial position of the communication nodes.

Second, includes the evaluation and control unit 2 Means for determining a transmission power of the send-willing communication subscriber C (PTc), which allows the associated communication subscriber D a high-quality reception of the data to be transmitted. A qualitatively sufficient reception of the data is present, for example, if known receiver-side data transmission correction methods can compensate for errors in the data transmission. This is the case, for example, when the received power (PRdc) of the data sent by communication subscriber C to communication subscriber D is greater than a predetermined value. This means is preferably supported via a model-based power calculation, which contains the desired reception power (PRdc) of the data to be transmitted by C at the associated communication subscriber D and the propagation losses (LBcd). For example, a fixed threshold value can be specified for PRdc. The propagation losses LBcd are preferably determined from a parameter model-based calculation which takes into account the relative position of the communication participants.

Third, includes the evaluation and control unit 2 Means for setting a transmission power (PTc). These means are preferably supported by the setting of the value determined on the basis of a model-based power calculation, which is optionally increased by a percentage or absolute power, to a sufficient reception power (PRdc) of the data to be transmitted by the communication subscriber C at the communication subscriber assigned to the communication subscriber C D to ensure. Alternatively, it is also possible to set a set transmit power setpoint.

Fourth, includes the evaluation and control unit 2 Means for determining the relative position between at least the send-willing communication participant C and the already received via the communication channel communication participant A. This means is preferably calculated from the absolute positions of the communication participants, the absolute positions of either the communication participants a priori known or via a satellite-based position determination unit , For example, a GPS receiver, are determined and can be communicated to other communication participants, for example via a control channel.

Fifth includes the evaluation and control unit 2 Means for determining the expected reception power (PRac) of the data to be transmitted by the communication subscriber C to at least one communication subscriber A already receiving the communication channel according to a set transmission power (PTc) and taking into account the relative position of the already receiving communication subscriber A to the communication subscriber C. Means is preferably supported via a model-based performance calculation. The calculation takes into account, for example, the parameters transmission power of the communication subscriber C (PTc), profit the transmitting antenna of the communication subscriber C (GTAc), receiving antenna of the communication subscriber A (GRAa), propagation loss in free space between the communication subscribers A and C (LBac) and propagation loss by weather between the communication subscribers A and C (LUac). The quantitative determination of the parameters taken into consideration preferably takes place via a priori available parameter quantities or by using suitable measuring methods and / or application of model-based parameter calculation methods. For example, the propagation loss between the communication parties A and C (LBac) is calculated using a parameter model. The parameter models can take into account the relative spatial position of the communication nodes.

Sixth, includes the evaluation and control unit 2 Means for evaluating a criterion, during which the expected reception power (PRac) of the data to be sent by the communication subscriber C at at least one already receiving via the communication channel E communication participant A qualitatively sufficient communication of the already receiving communication subscriber A with the associated, already sending communication participants B guaranteed. This means is preferably supported by the comparison of the expected signal-to-noise ratio (SigDifa) for the already-receiving communication subscriber A with a defined threshold value. In this case, the signal-to-noise ratio is determined, for example, as the absolute value of the difference between the expected reception power (PRac) of the data to be sent by the communication subscriber C at the communication subscriber A and the received power (PRab) of the data sent from the communication subscriber B to the communication subscriber A.

Seventh is the evaluation and control unit 2 equipped with means for generating the data to be sent by the communication subscriber C.

Eighth is the evaluation and control unit 2 equipped with means for activating and controlling the transmission process.

Preferably are all communication subscribers (A, B, C, D) of the wireless network according to the preceding Description trained.

The function of the communication subscriber C will now be described on the basis of in 1 illustrated situation explained. The communication subscriber C wishes to send data to a communication subscriber D assigned to the communication subscriber C in parallel via the same communication channel E when the data transmission between the communication users A and B has already taken place. In a first method step, the communication subscriber C willing to transmit determines the reception power PRab of the data F transmitted by the already transmitting communication subscriber B to the communication subscriber A already receiving the communication channel E according to FIG PRab = PTb + GTAb + GRAa - LBab - LUab Formula 1.

In this case, the transmission power PTb of the already transmitting communication subscriber B is determined from that of the receiving unit 1 the communication subscriber C received power PRcb the data sent from the already transmitting communication subscriber B and the propagation loss LBbc between the communication participants B and C according to PTb = PRcb + LBbc Formula 2.

The propagation loss LBbc is realized via a parameter-model-based calculation method, which incorporates the relative spatial position of the communication participants B and C. For example, this can be determined according to the following relationship LBbc = 10 * log ((4 * pi * deltabc) / lambda) Formula 3, wherein Deltabc represents the spatial distance between the communication parties C and B and lambda represents the wavelength of the radio transmission used. The spatial distance Deltabc of both communication participants B and C is determined by the evaluation and control unit 2 known absolute positions of the communication participants B and C. Similarly, the propagation losses LBab between the communication participants A and B can be calculated in formula 1.

In a second method step determines the evaluation and control unit 2 the transmission power PTc of the communication subscriber C, taking into account the relative position of the send-willing communication subscriber C and the associated, receiving communication subscriber D via a model-based power calculation according to PTc = PRdc - LBcd formula 4, wherein the required received power PRdc can be, for example, a predetermined value and the propagation losses LBcd are determined analogously to formula 3.

Third, evaluates the evaluation and tax Ness 2 of the communication subscriber C from a first criterion, in the fulfillment of the expected reception power PRac to be sent by the send-willing communication participant C data on the already receiving via the communication channel E communication participant A qualitatively sufficient communication of the already receiving communication participant A with the associated, already sending communication participants B guaranteed. This criterion is realized by the comparison of the probable signal-to-noise ratio (SigDifa) for the already receiving communication subscriber A with a defined threshold value. The signal-to-noise ratio is determined in accordance with SigDifa = abs (PRac-PRab) Formula 5, where PRac denotes the expected reception power of the data to be transmitted by the communication subscriber C at the communication subscriber A and PRab the receive power of the data sent by the communication subscriber B data to the communication subscriber A. If the signal-to-noise ratio SigDifa is greater than the specified threshold, then the first criterion is satisfied.

Furthermore evaluates the evaluation and control unit 2 of the communication subscriber C from a second criterion, in the fulfillment of the expected receiving power PRdb sent from the already transmitting communication subscriber B data on the communication partner C willing to send communication subscriber D ensures a qualitatively sufficient communication of the sendwilligen communication subscriber C with the associated communication subscriber D. This criterion is realized by comparing the probable signal-to-noise ratio (SigDifd) for the communication subscriber D assigned to the transmitting subscriber C with a defined threshold value. The signal-to-noise ratio is determined analogously to formula 5. If the signal-to-noise ratio SigDifd is greater than the specified threshold value, the second criterion is met. Are the first criterion, in the fulfillment of which the expected reception power PRac of the data to be sent by the communication subscriber C data at the already receiving via the communication channel E communication participant A ensures a sufficient quality communication of the already receiving communication participant A with the associated, already transmitting communication participant B, and the second criterion, in the fulfillment of which the expected reception power PRdb of the data sent by the already transmitting communication subscriber B to the communication partner D who is willing to transmit the communication subscriber D ensures a qualitatively sufficient communication between the communication subscriber C willing to send and the associated communication subscriber D, then begins Send the willing to send communication subscriber C via the communication channel E.

The invention has been explained by way of example examples of exemplary models for the calculation of received and transmitted powers and for the quantitative calculation of parameters on the basis of a parameter calculation model. It goes without saying that it is possible to use other models for calculating the reception and transmission powers and / or the use of further parameters. Other parameters take into account, for example, the effect of the environment and / or the spatial orientation of the communication participants to each other. It is also possible to use further parameter calculation models. The parameter-free determination of the received and transmitted powers is one possible embodiment. Notwithstanding the 2 illustrated embodiment, the use of a single antenna for the transmitting, receiving unit is sufficient 1 . 3 and satellite-based position-receiving unit 6 ,

A

communication stations

B

communication stations

C

communication stations

D

communication stations

e

communication channel

F

dates

1

receiver unit

2

evaluation and control unit

3

transmission unit

4

receiving antenna

5

transmitting antenna

6

Satellite-based position-receiving unit

7

receiving antenna

Claims (16)

Method for deciding on the parallel use of a common communication channel (E) of a radio network, in particular of a WLAN radio network, the radio network consisting of at least four communication subscribers (A, B, C, D), at least two communication subscribers (B, A), comprising at least one transmitting communication subscriber (B) and at least one associated receiving communication subscriber (A), already transmitting data (F) via a communication channel (E), in which at least one communication subscriber (C) willing to transmit requests a parallel data transmission over the communication channel (E) to at least one assigned communication subscriber (D) begin NEN, where at least one willing to send communication subscriber (C) has means for determining the relative position between at least the communication willing participants (C) and already on the communication channel (E) receiving communication participants (A), comprising the following steps: a) determination of Receiving power (PRab) of the data (F) transmitted by the already transmitting communication subscriber (B) to the communication subscriber (A) already receiving data via the communication channel (E), b) determining a transmission power (PTc) of the communication subscriber (C) willing to transmit c) determination of a transmission power (PTc) of the transmitting subscriber (C), d) determination of the anticipated reception power (PTac) of the data to be sent by the transmitting subscriber (C) at least at least one communication subscriber (A) already receiving data via the communication channel (E) according to the transmission power (PTc) set in c) and taking into account the relative position of the already receiving communication subscriber (A) to the communication subscriber (C) willing to send, e) evaluating at least one Criteria, in the fulfillment of which the expected reception power (PRac) of the data to be sent by the transmitting communication subscriber (C) at at least one already on the communication channel (E) receiving communication participants (A) a qualitatively sufficient communication of the already receiving communication subscriber (A) with the assigned, already transmitting communication subscriber (B) ensures, and f) sending data from the send-willing communication subscriber (C) to the associated communication subscriber (D) via the communication channel (E), if the criterion according to step e) is met. Method according to claim 1, characterized in that that the reception power (PRab) of the already receiving communication subscriber (A) in step a) taking into account the relative position of the already over the communication channel (E) communicating communication participants (B, A) and that of the party wishing to send (C) determined transmission power (PTb) of the already transmitting communication subscriber (B) over a model-based performance calculation is determined, the at least a parameter of the group transmission power (PTb), gain transmission antenna (GTAb), Gain receiving antenna (GRAa), propagation loss in free space (LBab), propagation loss due to weather (LUab) and other radio-related Contains parameters. Method according to claim 1 or 2, characterized that the transmission power (PTc) of the send-willing communication subscriber (C) taking into account the relative position of the communication subscriber willing to send (C) and the associated receiving communication subscriber (D) via a model-based performance calculation is determined at least a parameter of the group receive power (PRdc), gain transmit antenna (GTAc), gain receiving antenna (GRAd), outdoor propagation loss Space (LBdc), propagation loss due to weather (LUdc) and others radio-related parameters. Method according to one of the preceding claims, characterized in that the specification of a transmission power (PTc) of the send-willing communication subscriber (C) in step c) via a constant transmit power setpoint occurs when the constant transmit power setpoint greater or equal which is the transmission power determined in step b). Method according to one of claims 1 to 3, characterized the transmission power (PTc) of the transmitting subscriber (C) in step c) is set as the transmission power determined in step b) becomes. Method according to one of the preceding claims, characterized characterized in that the expected reception power (PRac) the one to be sent by the send-willing communication subscriber (C) Data on at least one already via the communication channel (E) receiving communication subscriber (A) in step d) under consideration the relative position of the already over the communication channel receiving communication subscriber (A) to the send-willing communication participant (C) and in step c) set transmission power (PTc) of the willing to send communication subscriber (C) over a model-based performance calculation is determined, the at least one Parameters of the group transmit power (PTc), gain transmit antenna (GTAc), Gain receiving antenna (GRAa), propagation loss in free space (LBac), propagation loss due to weather (LUac) and other radio-related Contains parameters. Method according to one of the preceding claims, characterized in that the evaluation of a criterion in step e), in the fulfillment of the expected reception power (PRac) of the data to be sent by the sendwilligem communication participant (C) at least one already over the communication channel (E) receiving communication participant (A) qualitatively sufficient communication of the already receiving communication subscriber (A) with the associated, already transmitting, communication subscriber (B) ensured from the calculation of the signal to noise ratio (SigDifa) for at least one, already on the communication channel (E) receiving communication subscriber (A) and the Comparison with a general and / or subscriber-specific threshold exists. Method according to one of the preceding claims, characterized characterized in that the relative orientation of the communication participants on mutual Communication of the absolute position of the communication participants he follows. Method according to claim 8, characterized in that that the absolute position determination over one to each communication participant associated satellite-based Position determination takes place. Method according to one of the preceding claims, characterized characterized in that the method steps a) to f) with information about the temporal Duration of channel usage of already existing communication via the Communication channel (E) linked become. Method according to claim 10, characterized in that that the temporal duration of the channel use of the already existing Communication as information in the of the already sending communication participants (B) transmitted data (F) is integrated. Method according to claim 10, characterized in that that the temporal duration of the channel use of the already existing Communication from the data size of the data sent to the already sending communication subscriber (B) (F) is calculated. Method according to one of the preceding claims, characterized characterized in that after step d) a determination of the received power (PRdb) that of at least one already transmitting communication subscriber (B) data (F) sent to the communication party willing to transmit (C) associated communication subscriber (D) takes place and after step e) the evaluation of at least one criterion is carried out, in the performance of which Receive power (PRdb) of the already transmitting communication subscriber (B) data (F) sent to the communication party willing to transmit (C) belonging Communication participant (D) a qualitatively sufficient communication with the party willing to send (C), and that the sending of data from the willing to send communication (C) to the assigned communication subscriber (D) via the Communication channel (E) takes place only if the criterion according to method step e) and the criterion, in the fulfillment of which the reception power (PRdb) of the already sending communication subscriber (B) sent data (F) to the send to the willing communication subscriber (C) belonging Communication participant (D) a qualitatively sufficient communication with the party willing to send (C), Fulfills are. Method according to claim 13, characterized in that that the received power (PRdb) of at least one already sending data (F) to the sending communication subscriber (B) the communication participant (C) assigned communication partner (D) taking into account the relative position of the already over the communication channel (E) sending communication subscriber (B) and the communicating party associated with the transmitting subscriber (C) (D) and that of the sendwilligen communication participant (C) determined Transmission power (PTb) of the already transmitting communication subscriber (B) over a model-based performance calculation is determined, the at least a parameter of the group transmit power (PTb), gain transmit antenna (GTAb), gain receiving antenna (GRAd), propagation loss in free space (LBbd), propagation loss due to weather (LUbd) and other radio-related Contains parameters. Method according to claim 13 or 14, characterized that the evaluation of at least one criterion, in the fulfillment of which Receive power (PRdb) of the already transmitting communication subscriber (B) data (F) sent to the communication party willing to transmit (C) assigned communication subscriber (D) a qualitatively sufficient Communication with the willing party (C) guaranteed from the calculation of the signal to noise ratio (SigDifd) for the the communication participant (C) assigned communication partner (D) and the comparison with a general and / or participant-specific Threshold exists. Communication participant in a radio network comprising at least one transmitting and receiving antenna ( 4 . 5 ), at least one transmitting and receiving unit ( 1 . 3 ) and at least one evaluation and control unit ( 2 ), characterized in that the evaluation and control unit ( 2 ) is equipped with first means, by means of which a received power (PRab) transmitted by an already transmitting communication subscriber (B) Data (F) can be determined at an already on the communication channel (E) receiving communication participants (A) that the evaluation and control unit ( 2 ) is equipped with second means, by means of which a transmission power (PTc) of the transmitter-willing communication subscriber (C) can be determined that the evaluation and control unit ( 2 ) is equipped with third means, by means of which a transmission power (PTC) of the send-willing communication subscriber (C) can be set, that the evaluation and control unit ( 2 ) is equipped with fourth means, by means of which a relative position between at least the send-willing communication subscriber (C) and the already via the communication channel (E) receiving communication participants (A) can be determined that the evaluation and control unit ( 2 ) is equipped with fifth means by which an expected reception power (PRac) of the data to be sent by the transmitting communication subscriber (C) to at least one already via the communication channel (E) receiving communication subscriber (A) according to a set transmit power (PTc) and under Considering the relative position of the already receiving communication subscriber (A) to the send-willing communication subscriber (C) can be determined that the evaluation and control unit ( 2 ) is equipped with sixth means, by means of which a criterion, in the fulfillment of the expected receiving power (PRac) to be sent by the sendwilligen communication participant (C) data on at least one already over the communication channel (E) receiving communication participants (A) a qualitatively sufficient Communication of the already receiving communication subscriber (A) with the assigned, already sending communication subscriber (B) ensures that it can be evaluated that the evaluation and control unit ( 2 ) is equipped with seventh means by means of which the data to be sent by the willing to send communication (C) can be generated and that the evaluation and control unit ( 2 ) is equipped with eighth means by which the transmitting unit ( 3 ) can be activated and controlled.