WO2008125345A1

WO2008125345A1 - Rfid-antenna system

Info

Publication number: WO2008125345A1
Application number: PCT/EP2008/003039
Authority: WO
Inventors: Gerald Schillmeier; Frank Mierke; Thomas Lankes
Original assignee: Kathrein-Werke Kg
Priority date: 2007-04-17
Filing date: 2008-04-16
Publication date: 2008-10-23
Also published as: DE102007018059A1; RU2009142221A; EP2137791A1; CA2683792A1; CN101657936A; BRPI0810421A2; JP2010527054A

Abstract

The invention relates to an improved RFID-antenna-system that is characterised by the following characteristics: the at least two patch antennas (21) are offset in relation to each other in the direction of the passage path (3) or at least with one component in the direction of the passage (3'), the at least two patch antennas (21) form a group of patch antennas (A, B) for grouping and for reducing the size of the monitoring area in the direction of the passage (3'), and the at least two patch antennas (21) are arranged at the same distance in relation to surface of the base (5) of the path of the passage (3) and/or on the same horizontal plane or are offset in relation thereto, such that a straight line passes through the centre and/or centre of gravity of at least two adjacent patch antennas (21) formed with the horizontal plane and/or a plane that is parallel to the surface of the base (5) at an angle α that is ≤ 45°.

Description

RFID antenna system

The invention relates to an RFID antenna system with an RFID antenna device for an electronic article security system (EAS) and with an RFID antenna device for a goods identification system (WIS) according to the preamble of claim 1 ,

In particular for securing goods, for example at the exit of department stores, shops, etc., so-called electronic article security devices are used. These consist of RFID antenna systems, which are arranged at a distance from one another in the region of the exit or a passage and between which the passageway to be monitored is formed.

The corresponding products and goods available in the store are secured, for example, by means of an electronic article security label. If the goods are properly paid for, the salesperson will remove the corresponding counterfeit label, so that the customer can use the Goods can easily pass through the monitored exit passage.

If the goods are still taken in the secured state through the monitored outlet path, an audible warning signal is generally output in the monitored area in order, for example, to report that an attempt is made to take unpaid goods out of the store.

Different electronic article surveillance systems have become known.

According to a known method, so-called radio-frequency labels (RF labels) are used. On such a radio-frequency label, a coil is provided whose terminal ends are capacitively connected to each other. As monitoring antennas transmitting antennas are used, which emit electromagnetic radiation, for example in a range of 6 to 10 MHz. If a corresponding RF label is passed through the monitoring area, it removes transmission energy from the system, which can be detected by means of a corresponding electronic evaluation device.

In addition, an electromagnetic method has become known in which to be secured on the goods long metal strips. These metal strips are made of a magnetizable alloy. If a product secured in this way is guided through the alternating magnetic field of the corresponding monitoring antennas which radiate, for example, at a frequency of 10 Hz to 20 KHz, this leads to a saturation magnetization of the metal strips, the steep flanks of the metal strips Magnetization generate harmonics in the alternating field, which are detectable.

The aforementioned EAS systems operate in the manner of a 1-bit transponder in which the presence or absence of a particular tag in the monitoring and reading area can be detected.

In addition to monitoring methods and systems, so-called UHF RFID methods are also used for article entry and identification. In this case, a product to be detected is provided with an RFID tag. This method offers to the above-mentioned method, first of all, the significant advantage that not only a single bit can be evaluated as information by means of an RFID tag, but that these UHF RFID tags are provided with a microchip on which information with a Word length can be stored from several locations and read from them. Preferably, so-called passive RFIDs are used which receive their energy for reading out the tag contents and returning the corresponding information from the electromagnetic field of the antenna system. The RFID tag consists of an antenna structure with the aforementioned microchip. To read the information is - as is known - a so-called. Reader is used, for example, the tags the necessary energy for operation through the electromagnetic field via an antenna system, the tags provided with the microchip then the stored information using this energy can send out a corresponding answer that can be read and evaluated via an antenna system and a downstream RFID reader. With regard to the structure of an RFID antenna system for an electronic article security system (EAS), reference is made, for example, to the prior art publication WO99 / 30384 A1. & Fundamentals and Applications in Contactless Smart Cards and Identification, Second Edition, Klaus Finke Zeller, Copyright ^® 2003, John Wiley & Sons, Ltd., ISBN: Similarly to the prior publication "three fundamental operating principles" in RFID Handbook is 0-470-84402 - 7, chapters 1.2, 1.3, 2.3 to 2.5.4 and 3.1 to 3.1.2.

In principle, it is desirable, in addition to an antenna system for an electronic article surveillance system (EAS), as mentioned, to use an antenna device, for example a UHF RFID antenna device, in order to set up a goods identification system therefor. This could be used to read out certain information about goods and products passing through the surveillance area, which are important for various processes.

From US 2006/0132312 Al, an antenna system is basically known, which can be installed in a passageway (doorway). For this purpose, different antenna systems can be used, namely for example an RFID antenna system consisting of patch antennas. Alternatively, so-called loop antennas or a so-called photonic band GAP antenna can be used.

The antennas described may, in addition to a passageway on an adjacent wall pointing in the front direction or in an actual door frame facing in the front direction or pointing backwards or else parallel to Passage direction extending in the actual archway be arranged radiating.

If patch antennas are used, several patch antennas can also be operated together, which are arranged one above the other in the vertical direction. In a further exemplary embodiment shown, a plurality of such patch antennas can be used, which are arranged to run in a plurality of branches in the vertical direction and operated together, wherein in a variant described so-called diversity switches or diversity combiners can be used for this purpose. However, it can not be deduced from this preliminary publication that this system can be used for an electronic article security system EAS and / or for a goods identification system WIS. At least this prepublication also does not reveal that an RFID antenna system can be constructed, which comprises antennas for an electronic article security system EAS and next to antennas for a goods identification system WIS.

It is therefore an object of the present invention to provide an improved RFID antenna system comprising on the one hand an antenna device for an electronic article security system and on the other hand an antenna device for a goods identification system (WIS) for reading out with a microchip Includes tags. This should be a fundamentally simple system, whereby it should be ensured that the different antenna systems should not adversely affect one another for the EAS system and also for the WIS system. In other words, one should optimal integration of both systems.

The object is achieved according to the features specified in claim 1. Advantageous embodiments of the invention are specified in the subclaims.

The present invention provides an extended RFID system for electronic article surveillance (EAS) on the one hand and for the realization of a goods identification system (WIS) on the other hand, which is characterized by its high integration capability and optimal use. The aforementioned goods identification system and the associated antenna device can also be retroactively retrofitted to an existing RFID antenna system for an electronic article surveillance system (EAS) without the function and mode of operation of this EAS system or of the goods Identification system is adversely affected by retrofitting.

The inventively improved system works on the basis of RFID technology.

In order to realize a simply constructed system with a high "hit rate" and high functional capability, the invention provides that the antenna system provided laterally by a passage area to be monitored comprises at least two antennas, these at least two antennas in the passage direction or at least with one component in the passage direction are arranged side by side. You do not necessarily have to be in the same altitude (for example, parallel to the level of the passageway), but can also be partially positioned at different altitudes. However, a line lying through the middle or center of gravity of the two adjacently arranged antenna systems straight line should have an angular deviation with respect to a horizontal plane (or a plane parallel to the passageway), which is preferably not greater than 45 °.

According to the invention, the UHF RFID system comprises patch antennas or consists of patch antennas. These have a particularly low overall height and can therefore easily be retrofitted into existing, often consisting of frame-shaped antennas EAS antenna system devices, for example, within the frame-shaped antenna of the existing EAS monitoring system.

The arrangement of two patch antennas, which are offset from each other with lateral offset in the passage direction or with a component in the passage direction, can be realized with simple means improved bundling of the surveillance area. This offers significant advantages insofar as correspondingly tagged goods or products are only detected and read out when a person with a product comprising a microchip RFID tag actually passes through the defined reading area (ie the surveillance area) and not only in passes near this reading area. This ensures above all that no too early detection is triggered by the fact that, for example, a person secured to the passage secured by two laterally positioned antenna systems only in the immediate vicinity (for example, still in the Loading) and a product secured with a tag can reach the detection and / or reading area of the antenna system.

The patch antennas according to the invention can be designed as individual patch antennas. However, they can also be designed as combined patch antennas, which are formed, for example, on a common ground plane, on a common substrate, etc., so that only the patch areas are arranged separately on this substrate. Here are any modifications possible.

In a particularly preferred embodiment of the invention, for example, at least two pairs of patch antennas are arranged one above the other at each side antenna device, ie at two different levels or planes (where the paired patch antennas, as mentioned above, are not necessarily the same Height level, but at least in the specified extent offset from each other can be arranged).

However, it is also possible that in the forward direction not only two but several antennas, for example three or more patch antennas, are used in order to reduce the bundling area and thus the narrowing of the monitored area in the direction of the passage to a narrow passage zone. In other words, a bundling of the antenna field and thus of the monitoring area in the horizontal plane takes place (with a horizontally extending passageway), so that a passage zone monitored by the antenna device is formed, which extends in the direction of the passageway 3 (as a rule in horizontal direction) only S -

extends over as low as possible.

In addition to the above-mentioned preferred variants, it has furthermore proved favorable, if appropriate in the lower transition region from the lateral limiting devices accommodating the antenna systems, to use the ground antenna (and / or the ceiling region) for additional antenna devices, in particular patch antennas, which are used for detection, also again in a preferred pairwise arrangement, namely in the forward direction offset from each other. Preferably, the at the transition region to the ground and / or in the transition region to a ceiling, the patch antennas may be mechanically pre-adjusted so that their main beam direction substantially not parallel to the plane of the passageway (the bottom surface), but deviating aligned with a vertically extending component are. In this way it is possible, for example, to orient some very upwardly arranged antenna systems with their main beam direction upwards, and to align very high antenna systems with their beam direction somewhat downwards. As a result, regardless of the positioning of the antennas, an optimization of the monitoring area can be carried out.

However, it is also possible, alternatively or additionally, to carry out an electronic alignment and / or adjustment of the antennas in order to preset the detection and / or reading area differently, at least to a certain extent, and thereby to optimize it. This can be realized, for example, by a predetermined or possibly also adjustable phase offset between two patch antennas arranged one above the other. Likewise, it is possible according to the invention to perform a phase offset by mechanically pre-adjusting and / or feeding two patch antennas adjacent to one another in the passage direction, whereby the area to be monitored can be adjusted out of a symmetry plane between the two patch antennas in one or the other direction of the passageway ,

According to the invention, the patch antennas can operate in linear or circular polarization. In particular, the circularly polarized operation of the patch antennas has advantages to the extent that it is ensured that a product tagged with RFID tags is always reliably detected and the information stored on the tag can be read out easily and completely, regardless of the orientation of the tag when passing through the reading area.

This RFID system preferably operates in the UHF range, for example in the 800 MHz to 1000 MHz range (in particular in the 800 MHz to 950 MHz range - for example 868 MHz range). The reading range of the patch antennas can be up to 1.5 m and more (for example, up to 2 m, etc.).

Further advantages, details and features of the invention will become apparent from the embodiments described with reference to various figures. In detail:

Figure 1: a schematic representation of a surveillance area or passage, wherein in the left antenna system serving the electronic article backup Antennas and the antennas provided for the goods identification system are indicated or shown by way of example;

FIG. 2 shows a schematic view of the UHF antenna arrangement according to the invention for an electronic article security system (EAS) in the direction of the transit view;

FIG. 3 is a schematic plan view of a patch antenna pair used;

4 shows a corresponding cross-sectional view parallel to the passage direction on the reproduced in Figure 3 patch antenna

Pair;

FIG. 5 is a cross-sectional illustration of an embodiment modified from FIG. 3;

FIG. 6 shows an embodiment of a patch antenna pair deviating from FIGS. 3 and 4;

FIG. 7 shows a further modified exemplary embodiment in plan view of the patch antennas used;

FIG. 8 shows a further detailed representation of a possible embodiment variant; and

FIG. 9 shows a simplified embodiment variant corresponding to FIG. 8. FIG. 1 shows the basic schematic structure of an electronic article security system (EAS) with two mutually offset antenna devices 1, between which a passageway 3 runs along a bottom surface 5 along the passage direction 3 '.

The antenna devices 1 are formed in the manner of lateral boundaries I ¹ , which essentially comprise a vertical or vertical extension 7 running transversely or in particular perpendicular to the bottom surface 5, a transverse or horizontal extension 9 running parallel or substantially parallel or with a component parallel to the passage 3 and a comparatively narrow designed thickness extension 11 transversely or perpendicular to the passage direction 3 'and thus in particular parallel to the bottom surface 5 have.

Between the relative to the passage 3 and the forward direction 3 ¹ left or right arranged to it

Antenna devices 1 and the side boundaries 1 "is a transversely to the passage 3 and transverse and in particular perpendicular to the passage 3 'extending passage zone formed, which is to be monitored by the antenna device.

A conventional EAS monitoring system is generally constructed in such a way that the antenna device in a side boundary I ¹ comprises, for example, one or preferably two approximately rectangular loop antennas 15, which are controlled accordingly.

A transmitting and / or evaluation unit 17 is preferably in Foot area 1 "of this page limit 1 is provided.

The control and evaluation of a so formed electronic article surveillance system (EAS) based on a so-called RFID technology belongs to the prior art and is sufficiently known in this respect. Reference is made in this respect to known methods and devices. Such systems typically operate in a frequency range of e.g. 10 Hz to 20 kHz (when, for example, an electromagnetic method is used or, for example, at 8 to 9 MHz (typically around 8.2 MHz) when, for example, a radio-frequency method is used).

In addition to the above-described antenna system for the electronic article surveillance system (EAS), a UHF RFID system is provided in the present case, which is used for goods identification. For this purpose, additional antennas are provided in the form of patch antennas.

As mentioned above, this system (WIS) serves, above all, through the use of tags with microchips to capture and read out product-related information, ie information about the goods on which the relevant tag is appropriate. Ultimately, however, in a further step, this information can also be used, in order ultimately to build up an electronic article surveillance device (if, for example, the product-related information stored on the tag is read out and, for example, compared with information stored via a cash register system in order to query it whether or not a product bearing the date has already been paid for). Already in Figure 1, a first embodiment of the UHF RFID goods identification system is shown in a schematic representation.

There are each a pair of patch antennas 21 in an upper region and another pair of patch antennas 21 in a lower region of the side boundary 1 'and the side antenna device 1 is arranged, in the illustrated embodiment when viewed transversely to the side boundaries within the frame-shaped loop antennas 15th

In the patch antennas are antennas, which in accordance with the illustration of Figure 3 in a vertical plan view and in Figure 4 in transverse view, a substrate 23rd

(of dielectric material or for example air), wherein above or below the substrate 23, an upper patch surface 25 and a lower lying

Ground surface 27 is provided. The patch surface 25 and the ground surface 27 are arranged at a distance 23 'corresponding to the thickness of the substrate 23 to each other.

4, the two patch antennas 21 are arranged parallel in front of a ground plane 31, in such a way that the lower ground plane 27 of the respective patch antenna 21 is galvanically isolated from the ground plane 31 (ie in a capacitive arrangement to) comes to rest. In this case, the ground plane 31 projects beyond the patchan antennas in plan view and projects laterally over the patch antennas in all directions. The ground surface 31 may consist, for example, of metal or a metal sheet or, for example, of a copper-coated printed circuit board. The fact that the ground plane 27 of the patch antenna 21 is galvanically isolated from the common ground plane 31 is particularly suitable when conventional patch antennas are used which, for example, are adhered to the ground plane 31 using an adhesive (if this is not electrically conductive). , In principle, a patch antenna mentioned with its lower ground surface 27 could also be placed directly on the ground plane 31 to produce a direct-current or galvanic contact. In this case, it is also possible in principle for example to dispense with the ground surface 27 located on the substrate, namely, namely, when the chip antenna is constructed directly with its substrate on the ground surface 31.

Further, in the illustrated embodiment in the lower common ground plane 31, a passage opening 31 ', in the respective patch surface 21 belonging to the ground surface 27 a congruent passage opening 27' and through the substrate 23 continuously through a passageway 35 is formed, so that through this entire arrangement a feed line 37 extends, which is electrically galvanically connected to the overhead patch surface 25 at a feed point 25 '.

Alternatively, however, a capacitive coupling in the region of the feed point 25 'with the patch surface 25 is possible. Finally, a feeding of the patch surface 25 is possible, for example, that the feed line 37 on the surface of the substrate 23 lying and / or running (ie plane-parallel to the plane of the patch surface) is connected to the patch surface, for example on Edge of the patch area. However, the patch surface can also have a U-shaped recess or the like, for example, so that the feed line extending in the plane of the patch surface 25 is further inwardly offset, for example, at the end of the U-shaped recess (ie opposite the peripheral edge of the patch surface). is electrically connected to the patch surface.

In the embodiment shown, the underlying ground surface 27 extends to the peripheral side surface 123 of the substrate 23, whereas in the plan view according to FIG

Figure 3 apparent patch surface 25 at a distance 39 in front of the

Side boundary or side surface 123 of the substrate 23 ends, that is formed in plan view with smaller longitudinal and transverse extension, as the lower ground surface 27 of the patch antenna 21st

In the embodiment shown, the at least approximately square-shaped surface of the patch antenna 21 is provided at two diagonally opposite corners with a chamfer 41, which serves to tune the antenna.

If air is used as the substrate 23, corresponding dielectric spacers serving only the mechanical support of the patch surface 25 would have to be used, over which the patch surface 25 is held and fixed at a distance from the ground surface 21.

Two patch antennas formed in accordance with the exemplary embodiment according to FIGS. 3 and 4 are arranged at a lateral distance 43 (ie in a clear lateral distance 43 between two side boundary surfaces 123 facing one another) two adjacent patch antennas), on a common ground plane 31.

In the exemplary embodiment shown, the distance between the two center points of the patch antennas or the centers of gravity of the two patch antennas is designated 45.

This center distance 45 should be greater than or equal to 0.2 times λ (lambda) with respect to the operating frequency of the patch antennas used, preferably the center wavelength of the frequency used, for example 0.2 × 34 cm _-1 5 cm are.

An optimal distance could be at

0.5 x λ (= 0.5 x 34 cm _^ 17 cm)

especially if, for example, the UHF RFID antenna system operates at a frequency of 868 MHz.

The patch antennas do not necessarily have to be the same or the same size. They also need not be arranged necessarily exactly in the horizontal offset, that is, in parallel direction to the forward direction 3 ^■ next to one another (it being understood in the illustrated embodiment that the extending in the horizontal direction of passage 3 'direction parallel to the bottom surface 5 extends).

It is further indicated with reference to FIG. 5 that a cooperating patch antenna pair does not basically have to be formed from two overall individual patch antennas 21, but have a common structure can.

The patch antenna pair according to FIG. 5 has a common ground plane 27 on the underside of a common substrate 23, wherein on the top side of the substrate 23 the two mutually separate patch surfaces 25 are formed, which are fed via a separate feed line 37 at a feed point 25 'at the associated patch surfaces 25 ends. The patch antenna pair thus formed is arranged at a small distance above the common ground surface 31, so that the ground surface 27 extends on the underside of the substrate in close proximity to the common ground surface 31.

The patch antenna pairs partially shown in the figures are arranged offset in the forward direction 3 'to each other. They do not have to be arranged exactly parallel to the passage direction 3 '. In particular, even if, for example, the passage is broadened or tapered, the lateral distance from a vertical plane lying in the passage direction 3 'to the relevant patch area 25 of a patch antenna 21 could be different. The mentioned patch antenna pair represents a basic embodiment of the invention in which at least two patch antennas 21 form a first group A of cooperating patch antennas. It can be arranged offset in the passage direction or with a component in the passage direction to each other but still several patch antennas, for example, three patch antennas, etc.

Referring to Figure 6, it is shown that such a cooperating pair of patch antennas 21 is not limited to Passage direction 3 ¹ , but also in the vertical or vertical direction 7 can be arranged with a certain offset to each other. However, a maximum deviation in height and / or vertical direction is preferably to be carried out such that a straight line 47 laid through the middle or center of gravity of the associated pair of patch antennas leads to a horizontal plane or to a plane parallel to the passageway or to the bottom surface 5 48 includes an angle α that is less than or equal to 45 °.

In addition, however, the patch antennas shown in FIGS. 1 to 6 could also be arranged twisted relative to one another, so that in the case of a patch antenna, the feed point 25 'is more at the top and at the adjacent patch antenna at the bottom or at the one antenna rather at the right and at the other patch antenna, for example, is more on the left side, etc. Again, there are basically no restrictions.

It is shown with reference to FIG. 7 that, for example, a group of four of patch antennas 21 or several groups of two or more groups of four etc. can be used in an antenna device 1.

In this case, in the embodiment according to FIG. 7, in addition to a lower or lower patch antenna group A (in the exemplary embodiment shown in the form of a patch antenna pair A), a second patch antenna group B is higher (in the embodiment shown in FIG Form of a higher-lying patch antenna pair B) is provided, although the higher-lying patch antenna pair B is arranged with a same vertical or vertical offset (which need not necessarily be so), but in Passage direction 3 'positioned differently from the lower patch antenna pair A. This results in a larger lateral offset 43 to 45 between the two patch antennas 21 of the patch antenna pair further up. As already mentioned, each of the mentioned groups A or B or each further patch antenna group can also have more than two patch antennas, which are arranged offset in the passage direction or at least in one component in the passage direction.

Notwithstanding the embodiment shown, the feed points 25 'but come to rest at different locations, so not all with the same same alignment, as shown in Figure 7.

The clearances 43 in the horizontal or passage direction 3 ¹ or in the vertical or vertical direction 7 can be of the order of magnitude of a few mm to a few cm (without any fundamental restriction to this size range).

In this embodiment, there is now the further advantage that, for example, the lower row A of patch antennas 21 relative to the upper row B of patch antennas 21 with a phase offset can be fed to each other, whereby an electric Up- tilt or, depending on the arrangement, if desired , a so-called electric down-tilt can generate. In other words, the main emission direction or main lobe is thereby electrically pre-set in ascending vertical orientation or rather in lowered vertical orientation. As a result, a specific fine adjustment of the surveillance area are made.

If, for example, the four patch antennas mentioned in FIG. 7 are used in the lower monitoring area X1 (FIG. 1) according to FIG. 1, the control of the patch antennas can be carried out in such a way that the monitored area is electrically preset from the lower floor upwards.

If such a patch antenna group shown with reference to FIG. 7 is used, for example, in the lower area of the antenna device 1 (as shown in FIG. 1), a different phase control with respect to the patch antennas arranged one above the other in the different rows or planes can take place such that For example, the main lobe or the main monitoring area is not perpendicular to the ground plane 31 of the patch antennas, but is aligned with a component in the vertical direction running upward.

If a corresponding patch antenna group according to FIG. 7 is used, for example, in the upper region X2 (FIG. 1) of the antenna device 1, a different phase feed could be carried out, for example, in such a way that the main beam direction of the patch antennas in a certain angular range tends to extend downwards into the surveillance region is aligned in it.

Likewise, however, the different phase control between the two patch antennas 21 of a group A and / or B arranged adjacent to one another approximately at the same height can take place in such a way that the alignment of the monitored area corresponds to the main beam direction (Direction of the main lobe) of the patch antenna in one or in an opposite direction with respect to the passageway 3 is deflected out of a transversely extending median symmetry plane out.

2 shows only schematically that additional patch antennas 21 may be provided, for example, additionally in the floor area or in the ceiling area or for example at the foot area 1 "of the antenna device 1 (or also at the upper end area of the antenna device 1) Preferably, however, a plurality of patch antennas offset in the direction of passage or with a component in the passage direction are also used, at least one pair of patch antennas or, for example, three, four or more patch antennas, in particular those provided at the lower foot region or at the upper end region In this case, patch antennas can also be aligned mechanically upwards or downwards, in particular if electronic beam shaping and alignment is not carried out, as explained above with reference to FIG Area of the side parts 1 'or in the bottom area or above the passageway (for example, in a ceiling or suspended from it) patch antennas used as additional patch antennas, individual patch antennas can be used here. Preferably, however, two or more patch antennas lying side by side in the passage direction or at least offset with one component in the passage direction are also used here, which thus form groups of patch antennas which interact. Based on Figures 1 and 2 and Figure 8 is further shown that, for example, the two side antenna devices 1, so the two side boundaries 1 'can be arranged at a side distance 51 from each other, for example, between 0.8 m to 2.5 m, in particular can vary between 1.4 and 2.0 m (although these limits can be undershot or exceeded).

Preferably, the lateral antenna device 1, ie the side boundary I ^1, a height 7, which may be, for example, 1 m to 1.80 tn or 2.0 m on average.

The height of a patch antenna or patch antenna pair, i. in particular the associated ground surface 31, for example, may preferably be between 5 cm to 40 cm.

If two patch antenna combinations 125a and 125b corresponding to FIGS. 1, 2 or 8 are used (ie a patch antenna combination A and a patch antenna combination B provided in the lower region X1 and in the upper region X2 according to FIGS. 1, 2 or 8) are), the distance 55 of the lower patch antenna combination 125a to the bottom surface should be at least 0.5 to 1 m. The distance 57 between the lower patch antenna combination 125a and the upper patch antenna combination 125b should preferably be between 0.1 m to 2 m, in particular around 0.2 m to 1.2 m. The distance can also be arbitrarily greater when particularly high side boundaries 1 'are used and the upper antenna devices are to be particularly. If only one patch antenna combination with associated ground plane 31 is used, as shown for example with reference to FIG. 9, then the distance of this patch antenna combination 125 to the bottom 5 should have a dimension of at least 0.5 m and more, the overall height of the arrangement again can be 1 to 2 m.

The patch antennas 21 used to enable an electronic goods identification system (WIS) preferably operate in the UHF frequency range, that is to say for example in an 800 MHz to 950 MHz or 1000 MHz range (in particular in the range of 868 MHz). , If this WIS system is used in addition to a conventional EAS monitoring system which operates without the patch antennas mentioned, it is preferred to use a conventional monitoring system, for example in the 10 Hz to 20 kHz (in particular in electromagnetic EAS methods) or for example in the 5 MHz to 10 MHz range (for example around 8, 2 MHz), in particular if it is a radio-frequency EAS method.

The patch antennas used in accordance with the invention are used for an RFID surveillance system, so that products, goods and / or persons etc. to be monitored can then be detected if they still carry an RFID tag, which is recognized during passage along the passageway and the corresponding information can be read out and evaluated by means of a "reader" provided for this purpose.

The system according to the invention has been described in particular with reference to a passageway. The monitoring system described in particular with reference to FIGS. 1 and 2 However, a passage gate along a passageway can also be constructed in such a way that corresponding side boundaries are arranged several times side by side at a lateral distance, for example five side boundaries I ¹ , whereby four parallel passageways 3 are defined. In the central antenna devices 1 (that is, not in the extreme antenna devices 1) then each patch antennas are installed so that they partially radiate in one and partly in the opposite direction for detecting both transmission paths.

Basically, the mentioned antenna devices 1 are used and monitored for monitoring a passageway so that in each case a pair of such antenna devices 1 is provided, ie in each case a corresponding antenna device 1 or a side boundary I ¹ , which are arranged opposite to the passageway to be monitored.

By means of the two patch antennas described, used in the forward direction, or also used in the forward direction, it is thus ensured that a smearing of the monitored area in the direction of the passageway is effected in view of a narrow passage zone as far as possible. In other words, there is thus a bundling of the antenna field and thus of the monitoring area in the horizontal plane (with a horizontally extending passageway), so that a passage zone (monitoring area) monitored by the antenna device extends in the forward direction 3 'only to the smallest possible extent.

Claims

Claims;

1. RFID antenna system with the following features: it is at least a first RFID antenna device (15) for an electronic article security system (EAS) and at least a second RFID antenna device (1) for a goods identification System (WIS) provided, by means of the at least one RFID antenna device (1) for the goods identification system (WIS) information from equipped with a microchip RFID labels (tags) are readable, the at least two RFID antenna devices (15, 1) are on one side with respect to a passageway (3) extending in the passage direction (3 ¹ ) or on two opposite sides with respect to a passageway (3) extending therebetween in a direction of inclination (3 ¹ ) to produce a passageway Surveillance area provided, characterized by the following further features, the RFID antenna device (1) with respect to the goods identification system (WIS) comprises at least two antennas, the are provided on one side of the passageway (3) to be monitored, - the at least two antennas for the goods identification system (WIS) consist of patch antennas (21), the patch antennas (21) of the RFID antenna device (1) respect. of the Goods Identification System (WIS) are parallel or substantially parallel or with a com- Component parallel to the passageway (3) aligned, the at least two patch antennas (21) in the direction of the passageway (3) or at least with a component in the forward direction (3 ¹ ) offset from each other, the at least two patch antennas (21) form for bundling and thus for narrowing the monitoring area in the forward direction (3 ¹ ) a patch antenna group (A, B), and the at least two patch antennas (21) are at an equal distance from a bottom surface (5) of the passageway (3) and / or the same horizontal plane or offset thereto, in such a way that a straight line through the center and / or center of gravity of at least two adjacent patch antennas (21) encloses an angle α relative to a horizontal plane and / or a plane parallel to the bottom surface (5) which is <45 °.

2. RFID antenna system according to claim 1, characterized in that in the forward direction (3 ') more than two patch antennas (21) are arranged with lateral offset to each other.

3. RFID antenna system according to claim 1 or 2, characterized in that a plurality of groups (A, B) of two or more mutually offset with side offset patch antennas (21) at different altitudes, in particular at different altitudes relative to the level of the bottom surface (5) are arranged to each other.

4. RFID antenna system according to claim 3, characterized in that two differently arranged at different altitude groups (A, B) of patch antennas (21) with different phase angle for generating a different up-tilt or down-tilt angle controlled are.

5. RFID antenna system according to claim 3 or 4, characterized in that at least two in the forward direction (3 ¹ ) offset from each other patch antennas (21) of a group (A, B) of patch antennas (21) are driven with different phase angle, about which the monitoring area in one or in the opposite direction to the passage direction (3 ¹ ) is adjustable.

6. RFID antenna system according to one of claims 1 to 5, characterized in that only one or more cooperating groups (A, B) of patch antennas in an RFID antenna device (1) are provided.

7. RFID antenna system according to claim 6, characterized in that the at least one or more cooperating groups of patch antennas are arranged at a height opposite the passageway (3) and / or the bottom surface (5) of the passageway (3) ≥ 0.3 m and ≤ 2 m.

8. RFID antenna system according to one of claims 1 to 6, characterized in that a plurality of areas (Xl, X2) are provided with one or more cooperating groups (A, B) of patch antennas (21), which in a lower height range of the RFID antenna device (1) or side boundaries (I ¹ ) and one higher-lying Area of the RFID antenna device (1) or the side boundaries (I ¹ ) are arranged.

9. RFID antenna system according to claim 8, characterized in that arranged between two offset in vertical and / or height direction provided areas (Xl, X2), one or more cooperating groups

(A, B) antenna devices comprising patch antennas (21) have a height distance of at least 0.1 m, and preferably less than 2.0 m, 1.2 m and preferably less than 0.6 m, and that the height distance of the bottommost patch antennas (21) or a lowermost group of patch antennas (21) to the bottom surface (5) of the passageway (3) at least 0.3 m, preferably 0.3 m to 1.5 m or in particular to 1.2 m is.

10. RFID antenna system according to one of claims 1 to 9, characterized in that the patch antennas (21) radiate in the UHF range, preferably in the 800 MHz to 1000 MHz band, in particular at 868 MHz.

11. RFID antenna system according to one of claims 1 to 10, characterized in that the patch antennas (21) comprise a patch surface (25), an underlying substrate (23) and an underlying ground surface (27), and that the thus formed patch antenna (21) is capacitively arranged in front of a ground plane (31) or DC-connected or electrically connected to the ground plane (31), the patch antenna (21) and the ground plane (31) transversely and preferably perpendicular to the passageway (3) and / or to the passage direction (3 ¹ ) is aligned.

12. RFID antenna system according to one of claims 1 to 10, characterized in that the patch antenna (21) comprises a patch surface (25), a substrate underneath (23) and a ground surface (31), wherein the patch antenna (21) and the ground surface (31) is oriented transversely and preferably perpendicular to the passageway (3) and / or to the passage direction (3 ¹ ).

13. RFID antenna system according to claim 11 or 12, characterized in that the substrate (23) consists of a dielectric body.

14. RFID antenna system according to one of claims 11 to 13, characterized in that the substrate (23) consists of air and the electrical spacers for positioning and holding the patch surface (25) are provided.

15. RFID antenna system according to one of claims 1 to 14, characterized in that at least one group (A,

B) of patch antennas comprises at least two mutually offset patch antennas (21) which are arranged in front of a common ground plane (31).

16. RFID antenna system according to claim 15, characterized in that a group (A, B) of at least two patch antennas (21) comprise a common substrate (23), on whose backside preferably a common ground surface (27) is provided, wherein on the emitter side on the substrate (23) opposite to the ground surface (27) at least two galvanically separated patch surfaces (25) are formed.

17. RFID antenna system according to one of claims 6 to

16, characterized in that each patch antenna (21) comprises a feed line (37) having a passage opening

(31 ') in the ground plane (31), an adjoining passage opening (27') in the respective ground plane (27) of the patch antenna (21) and an adjoining and extending through the substrate (23) channel ( 37) to a feeding point (25 ') passes through the patch surface (25), wherein the feed point (25') is preferably located on the underside of the patch surface (25).

18. RFID antenna system according to one of claims 1 to

17, characterized in that a group (A, B) of patch antennas (21) in front of a common ground surface (31) is arranged, the height dimension is preferably between 5 cm to 40 cm.

19. RFID antenna system according to one of claims 1 to 18, characterized in that preferably additional

Patch antennas (21) are provided, which are preferably provided in the lower region of the RFID antenna device (1) and / or the side boundary (I ¹ ) at the transition region to the bottom surface (5) whose main radiation direction and / or patch surface (25) preferably with a is directed forward facing vertical component.

20. RFID antenna system according to one of claims 1 to 19, characterized in that one or more patch chan- antennas (21) are preferably provided at the upper end of the RFID antenna device (1) and / or the side boundaries (I ¹ ) , whose main beam direction and / or patch surface (25) with a downward Vertical component are mounted in advance.

21. RFID antenna system according to one of claims 1 to

20, characterized in that at least two in the passage direction (3 ¹ ) and / or at least two offset in height and / or vertical direction to each other, cooperating patch antennas (21) are provided which are driven with different phase and preferably different adjustable phase are.

22. RFID antenna system according to one of claims 1 to

21, characterized in that preferably in the region of the bottom surface (5) and / or above the passageway

(3) at least one and preferably a plurality of patch antennas (21) offset from one another in the forward direction (3 ¹ ) are provided.

23. RFID antenna system according to one of claims 1 to

22, characterized in that the patch antenna (21) in a to an electronic article security system

(EAS) belonging antennas and / or loop antennas (15) are retrofitted and / or integrated.

24. RFID antenna system according to one of claims 1 to 23, characterized in that a plurality of RFID Antennenein- directions (1) and / or side boundaries (I ¹ ) are arranged with lateral offset to form a plurality of extending therebetween passageways (3) in which patch antennas (21) are installed in the middle RFID antenna devices (1) and / or lateral boundaries (I ¹ ), which are partially in one direction and partly in the direction opposite thereto for monitoring two adjacent passageways (3). radiate.

25. RFID antenna system according to one of claims 1 to 24, characterized in that the article-insurance system (EAS) belonging frame antennas (15) are provided, and that at least one patch antenna (21) in a loop antenna (15) is integrated, and that preferably the patch antennas (21) are integrated in plan view of the loop antennas (15) within the loop antennas (15).