CN103000989A - Micro-strip antenna with reduced rear lobe of Fresnel zone - Google Patents
Micro-strip antenna with reduced rear lobe of Fresnel zone Download PDFInfo
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- CN103000989A CN103000989A CN2012104254309A CN201210425430A CN103000989A CN 103000989 A CN103000989 A CN 103000989A CN 2012104254309 A CN2012104254309 A CN 2012104254309A CN 201210425430 A CN201210425430 A CN 201210425430A CN 103000989 A CN103000989 A CN 103000989A
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Abstract
The invention provides a system and a method and relates to an antenna structure, wherein the antenna structure has a reduced rear lobe of a Fresnel zone. According to the one embodiment of the invention, a patch antenna structure comprises one or a plurality of rear-lobe Fresnel zone reduction mechanisms for reducing the rear lobe of the Fresnel zone, without influencing the property of the main lobe of the antenna. The rear-lobe Fresnel zone reduction mechanisms are placed on or close to the boundary of the rear lobe of the Fresnel zone and can be applied to a side-view RF reader of a non-stop electronic toll collection to provide masking signals, without the need of any interrogator-responder.
Description
[technical field]
The present invention relates to antenna, the microstrip antenna (microstrip antenna) of the episternites Fresnel field that reduces particularly can be provided.
[background technology]
Various forms of radio frequencies (RF) signal and communication have been used for many years in such as wireless speech and data communication, monitoring, airborne vehicle and vehicle identification, navigation system etc.No-stop charging system (ETC) is a nearest example that uses radiofrequency signal.The ETC system can be used for for example electronic charging in turn pike, bridge, tunnel, parking lot etc., so the delay that elimination or minimizing cause because of Car park payment.During operation, the ETC system identification is by the vehicle of toll site, and the corresponding expense of deduction from registered vehicle car owner's account electronically.
Open road toll system (ORT) is a kind of ETC, and it does not arrange tollbooth at the toll site place.Therefore, the main benefit of ORT is that the user can cross toll site with highway speed, and does not need to stop to pay dues.The enforcement of this ORT ETC can save the vehicle time, need not website at charge machine place, therefore allows to travel with higher average speed.Except bringing convenience to the user, ETC also builds to the private enterprise and Operating cities' super expressway offers convenience, and also makes at minority city enforcement Congestion Pricing and becomes feasible, travels in the most crowded zone with the restriction vehicle.
Structure such as the ORT system of major part ETC system all are to settle a RF reader at the toll site place, launch a request signal (as using a directional antenna beams main lobe to certain specific the lane in which the drivers should pay fees emission request signal), in order to identify the vehicle of process.Correspondingly, each vehicle that participates in the ETC plan can be equipped with transponder, with the request signal of response RF reader, and replys a response signal, is used for identification relevant vehicle and/or ETC account.When vehicle is inquired by the request signal of RF reader through a toll site, the ad hoc response signal of transponder is just received (as using Dedicated Short Range Communications, (DSRC)) by this RF reader, then be passed to central computer and go to calculate corresponding expense (as based on specific toll site, time etc.), and from registered user's account, deduct.Therefore, above RF reader and ETC transponder all are for automotive vehicle identification (AVI) process, so the identity of charge vehicle is determined in toll site.
But the ETC system does not always have vicious in charge.For example, the RF reader need to be placed on a side of the lane in which the drivers should pay fees, main lobe is aimed at and is crossed this track (place on the overhead road sign frame with respect to the RF reader, main lobe is aimed at this track downwards) and covers various vehicle structures (as from the motorcycle to the double-decker bus) in order to hold.This side-looking RF reader, may make the antenna beam main lobe not only cover this specific the lane in which the drivers should pay fees (wherein the vehicle transponder can be asked), also can cover contiguous track (such as cash track, the lane in which the drivers should pay fees that own RF reader is arranged, Reverse Commuting track etc.).So, the vehicle that is loaded with the ETC transponder on so contiguous track probably by the charge of ETC mistake (for example, on the cash track except cash payment also by electronic charging, by the RF reader electronic charging on two ETC thes lane in which the drivers should pay fees, direction has but been received the expense of both direction although only travelled, etc.).
For the RF reader interrogates that prevents side-looking and the transponder on this uncorrelated track of RF reader, between contiguous track, set up the RF screen, technical is possible.But this RF screen does not provide desirable solution.For example, want really effectively, usually need this this track of RF screen capping in toll site, this is so that the RF screen is unrealistic.And, usually need the RF screen hole to be arranged in order to can vision pass this screen, for example can see often that the fee collection personnel pass the toll plaza.
[summary of the invention]
The system and method that the present invention relates to provides antenna structure with the back lobe Fresnel region that reduces (being reduced to the signal communication that is enough to prevent in the unwanted or unacceptable Fresnel region).The embodiment of the invention comprises a kind of patch-antenna structure, wherein there are one or more back lobe Fresnel region reduction means to be used for reducing the back lobe Fresnel region of line on another day, the main lobe characteristic of this antenna of not negative effect (no matter be far-field region, Fresnel region, or near-field region) again.Back lobe Fresnel region reduction means is positioned at or very near the boundary (as being positioned at back lobe near-field region/Fresnel region boundary) of back lobe Fresnel region.Perhaps in addition, back lobe Fresnel region reduction means can be positioned at any position of the back lobe Fresnel region of the Fresnel field antenna structure that back lobe reduces.
The Fresnel field antenna that back lobe reduces can be used for various different situations.For example, the Fresnel field antenna that back lobe reduces can be used for the side-looking RF reader of ETC system, so that being provided, masking signal avoids unintentionally interrogator-responder (as side-looking RF reader is housed on the lane in which the drivers should pay fees, and the transponder on the track of contiguous the lane in which the drivers should pay fees is asked AVI and charge).The Fresnel field antenna that back lobe reduces is placed by side-looking, so that main lobe emission masking signal covers a masking regional (such as the above-mentioned contiguous track of a part), and the back lobe Fresnel region that reduces has prevented that masking signal from disturbing side-looking RF reader normally to the inquiry of transponder.
Aforementioned feature of the present invention and the technical advantage set forth quite widely is thus with following detailed description of the present invention easier to understand.Other Characteristics and advantages of the present invention will described thereafter, and this consists of claim part of the present invention.It will be understood by those skilled in the art that concept disclosed here and specific embodiment can be used as a basis, be used for revising or designing other structure and carry out identical purpose of the present invention.Those of ordinary skills should be realized that also this structure that is equal to does not have to break away from the spirit and scope of the invention of being set forth by claims.No matter be counted as the novel features of feature of the present invention, be its tissue or operation method, with other purpose and advantage, by following description also by reference to the accompanying drawings, will be better understood.But, it is emphasized that each accompanying drawing only is as describing and narration, be not intention restriction the present invention.
[description of drawings]
In order more completely to understand the present invention, now by reference to the accompanying drawings with reference to following description, wherein:
Figure 1A and 1B are the signal gain orientation diagrams of directional antenna structure;
Fig. 2 shows the radiation pattern district of antenna lobe;
Fig. 3 A and 3B show the Fresnel field antenna that the back lobe of the embodiment of the invention reduces.
Fig. 4 shows the signal gain orientation diagram of the directional antenna structure with back lobe Fresnel region reduction means of the embodiment of the invention, and the signal gain orientation diagram that does not have the directional antenna structure of back lobe Fresnel region reduction means;
Fig. 5 shows the antenna element that comprises back lobe Fresnel region reduction means of the embodiment of the invention;
Fig. 6 shows the open highway toll structure of a no-stop charging system, and wherein side-looking less radio-frequency reader bit is used for identification approach vehicle in a toll site;
Fig. 7 shows the antenna element that comprises the Fresnel field antenna structure that a back lobe reduces of the embodiment of the invention, in order to provide in the open highway toll structure of no-stop charging system the controlled of request signal is sheltered.
[detailed Description Of The Invention]
Figure 1A and 1B have shown the signal gain azimuth view of typical directional antenna structure, such as antenna patterns illustrated 100A and 100B.For example, can provide the antenna such as the signal gain of antenna patterns illustrated 100A representative in illustrated embodiment, can be a micro-strip paster antenna structure.From the feature of antenna patterns illustrated 100A and 100B, can see, this antenna has short transverse, wherein have very high front and back than (be the main lobe gain amplitude to the ratio of back lobe gain range, or the lobe pair that has highest-gain along antenna axial direction and antenna axial direction quadrature has ratio than the lobe of low gain).Particularly, in the embodiment shown in Figure 1A, the peak value 111A of main lobe 110A approximately is 7dB, and the peak value 121A of back lobe 120A approximately is-15dB, and therefore front and back are 22dB than approximately.The peak value 111B of the main lobe 110B of structure shown in Figure 1B and the peak value 121B of back lobe 120B have similar high front and back ratio, and wherein front lobe and back lobe have more clearly boundary.
Be understandable that the same with many typical directional antennas although back lobe is quite little, antenna patterns illustrated 100A and 100B remain and comprise an obvious back lobe composition.The axial antenna lobe of directional antenna not, back lobe described above can produce unwanted signal communication (it is undesired or unwanted namely communicating by letter with the signal of direction in those zones of antenna).Therefore, have need control (namely greatly reducing) one or more such antenna lobes.
Fig. 2 shows the radiation pattern district in the antenna lobe (such as main lobe 110A, 110B and back lobe 120A, 120B).Can see that from Fig. 2 kind radiation pattern comprises a plurality of radiation areas.Particularly, Rayleigh (Rayleigh) or near-field thermal radiation district are in the antenna patterns illustrated district from antenna surface to the about λ of distance antenna surface/2 π, and Fresnel (Fresnel) radiation area is to the about 2D of distance antenna surface from the about λ of distance antenna surface/2 π
2/ λ place, Frauhofer (Fraunhoffer) or far-field radiation district are from the about 2D of distance antenna surface
2/ λ place is to apart from the about (2D of antenna surface
2/ λ)+and the λ place, wherein λ is the wavelength of radiation signal, D is the length (according to embodiment, D≤10 λ or D≤5 λ) of antenna itself.The characteristics near field are not have radiation to occur, and the near field is pure induction field (has signal to exist such as the near field, but can not propagate into away from antenna), therefore along with the distance from antenna increases, will decline rapidly.On the contrary, the characteristics in far field are that this is pure radiation field, so to this not induction, therefore along with the distance from antenna increases, decline slowlyer.The characteristics of Fresnel field are that it is the transition region between near field and the far field, therefore has induction field and two kinds of features of radiation field concurrently.
Near-field region normally from the scope of antenna close to very, therefore can ignore under many circumstances (unless using near-field communication (NFC), radio frequency identification (RFID) and Magnetic resonance imaging (MRI)).But Fresnel region then has a segment distance from antenna, is useful in some cases.For example, when when the 2.5GHz frequency range is moved, the Fresnel region of antenna (such as a micro-strip paster antenna) just appears at the back lobe radiation field pattern approximately in the scope of 0.02 meter to 0.8 meter of antenna surface.Therefore Fresnel region is influential in communication, interference, electromagnetic wave energy absorptivity (SAR) etc.But Fresnel region is a mixed zone, has two kinds of features of induction field and radiation field concurrently, and this is so that Fresnel region is very difficult to analysis and understanding.
The embodiment of the invention provides an antenna structure, comprise one or more back lobe Fresnel region reduction means, it provides a back lobe Fresnel region that reduces (such as having dwindled widely, preventing from occurring unwanted or unacceptable signal and communication in this Fresnel region).Fig. 3 A and 3B show the Fresnel field antenna structure that back lobe reduces.Particularly, Fig. 3 A shows the end view of the Fresnel field antenna 300 that back lobe reduces, and Fig. 3 B shows the front view of the Fresnel field antenna 300 that back lobe reduces.
The Fresnel field antenna 300 that the back lobe of illustrated embodiment reduces comprises antenna element 310, its at a specific RF frequency band range interior resonance (as in the frequency range of a Gigahertz, for example on the frequency band from 2.4GHz to 2.5GHz), be used for emission and/or receive signal.For example, antenna element 310 can be a micro-strip paster antenna structure, the copper sheet of conducting plane 311(as being connected with the signal and communication circuit wherein) separate mutually with ground plane 312 juxtapositions (be connected to the ground connect such as copper sheet) and by a dielectric material (such as FR-4 printed circuit board material, insulating support, air etc., showing among Fig. 3).It is conductor squares that the conducting plane 311 of illustrated embodiment has an antenna length D(such as conducting plane 311, and the length of side is D).Such micro-strip paster antenna structure can provide the antenna gain such as antenna patterns illustrated 100A among Figure 1A.
The Fresnel field antenna 300 that the back lobe of illustrated embodiment reduces comprises back lobe Fresnel region reduction means 320, it can reduce the back lobe Fresnel region of this antenna greatly, but the main lobe feature of this antenna of not negative effect (no matter be far field, Fresnel field, or the near field).The back lobe Fresnel region reduction means 320 of present embodiment places antenna element 310 afterwards apart from the d place.For example, the back lobe Fresnel region reduction means 320 of present embodiment places or very close back lobe near field/back lobe Fresnel region border, so d ≈ λ/2 π (such as d=λ/2 π ± 5%).According to the preferred embodiment of the present invention, chosen distance d wants so that back lobe Fresnel region reduction means 320 is positioned at the back lobe Fresnel region (such as λ/2 π≤d≤2D
2/ λ).
Although the embodiment of Fig. 3 A and 3B has shown single back lobe Fresnel region reduction means, the Fresnel field antenna structure that the back lobe of present embodiment reduces can have a plurality of back lobe Fresnel region reduction means.Each back lobe Fresnel region reduction means can be placed on any position in the back lobe Fresnel region of the Fresnel field antenna structure that this back lobe reduces.This back lobe Fresnel region reduction means can be take the periodically corresponding placement of antenna running frequency (such as the distance of separation placed as signal wavelength (λ) or its mark), can be placed on the position that optimum (minimizing of the maximization of dwindling such as the back lobe Fresnel region, main lobe performance impact) is provided, etc.According to one embodiment of present invention, the first back lobe Fresnel region reduction means is placed on the first back lobe Fresnel region boundary (such as the border between back lobe near field and the back lobe Fresnel region), and the second back lobe Fresnel region reduction means is placed on the second back lobe Fresnel region boundary (such as the border between back lobe Fresnel region and the back lobe far field).
Back lobe Fresnel region reduction means 320 preferably can reduce the back lobe Fresnel region of antenna element 310 greatly, but does not change antenna performance (such as S-parameter and front and back than still remaining unchanged).For example, although having increased back lobe Fresnel region reduction means 320, antenna element 310 can greatly reduce the back lobe Fresnel region, but its antenna patterns illustrated and do not have the not too large change of antenna patterns illustrated of the antenna element 310 of back lobe Fresnel region reduction means 320, as shown in Figure 4 (wherein antenna patterns illustrated 410 is the orientation gains that do not have the antenna element 310 of back lobe Fresnel region reduction means 320, and antenna patterns illustrated 420 is orientation gains that the antenna element 310 of back lobe Fresnel region reduction means 320 is arranged).
The back lobe Fresnel region reduction means 320 of present embodiment comprises a ground level (such as the conducting plane that is connected with ground), and induction and the radiation signal trait-treatment interaction of itself and Fresnel region reduce the appearance of Fresnel region in the antenna patterns illustrated greatly.For example, in the back lobe Fresnel radiation area of antenna field shape, provide ground conductor plane except aforesaid, the size and dimension that can also change back lobe Fresnel region reduction means with induction and the radiation signal trait-treatment interaction of Fresnel region, and reduce Fresnel region in the antenna patterns illustrated.Therefore, the shape of the back lobe Fresnel region reduction means of Fig. 3 A and 3B illustrated embodiment is to shape that should antenna element.The size of the back lobe Fresnel region reduction means 320 of embodiment than the size of corresponding antenna element 310 (according to embodiment, the length of back lobe Fresnel region reduction means is 1.05*D or 1.10*D) larger a little (such as large 5% or 10%), with induction and the radiation signal trait-treatment interaction of optimization and Fresnel region.Perhaps in addition, the back lobe Fresnel region reduction means of embodiment can cooperate the peak current that minimizes on the back lobe Fresnel region reduction means, therefore more effectively with induction and the radiation signal trait-treatment interaction of Fresnel region.
The back lobe Fresnel region reduction means 320 of embodiment can have a loss ferrite coating (lossy ferrite coating) thereon, to minimize the peak current on this back lobe Fresnel region reduction means.Perhaps in addition, the back lobe Fresnel region reduction means 320 of embodiment can have super material (metamaterial thereon, as have architectural characteristic such as the engineering material of periodicity macroscopic view mushroom (periodicmacroscopic mushroom) or other shape and structures), to minimize the peak current on this back lobe Fresnel region reduction means.Also can use other technologies, as the slit is set on the conductive plane of back lobe Fresnel region reduction means suitably, be used for minimizing the peak current on the back lobe Fresnel region reduction means, with more effectively with induction and the radiation signal trait-treatment interaction of Fresnel region, and greatly reduce Fresnel region in the antenna patterns illustrated.
Should be appreciated that the structure of back lobe Fresnel region reduction means 320 reduces the back lobe Fresnel region except above-described, can also be used for providing other functional.For example, the rear surface of back lobe Fresnel region reduction means 320 (with the opposing surface of antenna element 310) can be used as the support that circuit is installed, as provides a signal to antenna element 310 or receive the circuit of signals from antenna element 310.Believe that this circuit supporting structure is particularly suitable for adopting above-mentioned setting with the place (as by the service wear ferrite) of the peak current that minimizes back lobe Fresnel region reduction means, because highly compact type structure is provided, wherein circuit has minimum on antenna performance or not impact.
The Fresnel field antenna structure that reduces according to the back lobe of this concept can also comprise sensing element except above-mentioned antenna element and back lobe Fresnel region reduction means.For example, the Fresnel field antenna 300 that reduces of the back lobe of illustrated embodiment comprises base plate 330.Base plate 330 provides a reflector relevant with antenna element 310, improving the directivity of antenna structure, and improves the operation in main lobe far field, and this is known prior art.Importantly, although back lobe Fresnel region reduction means 320 place between antenna element 310 and the base plate 330, on the almost not impact of operation of the base plate 330 relevant with antenna element 310.That is to say that back lobe Fresnel region reduction means 320 is configured to except affecting the back lobe Fresnel region, the impact of the antenna 300 operation aspects, Fresnel field that back lobe is reduced reaches and minimizes.
An exemplary cellular construction of the Fresnel field antenna 300 that back lobe reduces is illustrated in figure 5 as antenna element 500.Embodiment shown in Figure 5 is a suitable compact structure, and its housing 510 surrounds conducting plane 311 and the ground level 312 of antenna element 310, and back lobe Fresnel region reduction means 320, and signal circuit 520 is arranged on it.Shell 510 is weather-proof, a RF transparent outer cover preferably, to protect and to hold with upper-part.The base plate 330 of illustrated embodiment places outside the shell 510, such as because its size and/or from the interval (as providing a less shell sizes to hold the parts that need most protection) of antenna element.Should be understood that cellular construction such as unit 500 are fit to the application of various situations very much, no matter provide RFDC, or AVI use etc.
The Fresnel field antenna 300 particularly suitable application that the back lobe of embodiment reduces are exactly the operation of ETC system.For example, the Fresnel field antenna 300 that back lobe reduces can be used for the side-looking RF reader of ETC system, so that a masking signal (masking signal) to be provided, be used for avoiding transponder to respond unintentionally (the side-looking RF reader interrogates transponder such as the lane in which the drivers should pay fees is used for AVI and charge, the transponder response in the track of contiguous the lane in which the drivers should pay fees).
Referring to Fig. 6, shown the ORT structure of ETC system, wherein RF reader 611 places toll site, is used for identifying the vehicular traffic of participation charge treatment system 615 and charging.RF reader 611 can comprise a unit, and its shell covers an antenna and circuit thereof, with emission one request signal in a zone of toll site, launches request signals such as request signal main lobe 612 to a part of the lane in which the drivers should pay fees 601.When vehicle 621 process toll site, transponder 613 is asked, and then provides response signal and identifying information to charge treatment system 615, in order to identify vehicle 621 and/or corresponding ETC account.Charge treatment system 615 can comprise system and a command adapted thereto collection based on processor, with suitable operation from from the information of transponder and identify vehicle and/or ETC user account number, calculate suitable expense (as based on specific toll site, time etc.), and charge to registered user's account number.
But the RF reader 611 that should be understood that structure shown in Figure 6 places the side (such as the side-looking structure) of the lane in which the drivers should pay fees, and request signal main lobe 612 covers and passes track 601, can hold most vehicle structure (such as from the motorcycle to the double-decker bus).This side-looking RF reader structure is so that request signal main lobe 612 also covers contiguous track 602 except covering the lane in which the drivers should pay fees 601.Therefore, the transponder 614 that crosses the vehicle 622 in contiguous track 602 also may be by 611 inquiries of RF reader, although be not to travel in the lane in which the drivers should pay fees 601 of RF reader 611 operation charges, vehicle 622 still charged improperly treatment system 615 and charged.
Make it not cover contiguous track 602 although also RF reader 611 can be put again the position, the pendulum position of this RF reader is processed normally undesirable.For example, arrange RF reader 611 so that allow passing through and avoiding covering contiguous track 602 of quite large vehicle such as double-decker bus, this can probably fail suitable covering the lane in which the drivers should pay fees 601, so fail to inquire should be identified and the vehicle transponder of charging on the lane in which the drivers should pay fees of travelling.The turn pike management board of operation ETC is unwilling to adopt the system configuration that may receive less a large amount of expenses especially.Similarly, he may adopt a cover instruction set (such as software) of charge treatment system 615, to prevent Double Dipping situation (for example, the charge place of vehicle 622 in contiguous track 602, in time very approaching charge in track 601).But the turn pike management board of operation ETC also is unwilling their test and operational system are changed fully.
The Fresnel field antenna structure that the embodiment of the invention utilizes back lobe to reduce provides a masking signal, avoids incorrect charge, and don't needs to change existing ETC infrastructure.For example, as shown in Figure 7, antenna element 500 comprises the Fresnel field antenna 300 that back lobe reduces, place the side-looking structure, so that masking signal main lobe 751 covers the blasnket area (the contiguous track of a part that covers as also being asked signal main lobe 612) in contiguous tracks 602, masking signal prevents that transponders in the contiguous track 602 are by 611 inquiries of RF reader.For example, the signal circuit 520 of antenna element 500 can provide a carrier wave or other signals (such as the signal that moves in the frequency band identical with the request signal of RF reader 611 emissions or passage) with the generation interference relevant with request signal, thereby stops RF reader 611 interrogator-responder in masking signal main lobe 751 districts.
Should be understood that from structure shown in Figure 7 the back lobe 752 of antenna element 500 is side-looking structures, it points to the lane in which the drivers should pay fees 602, the interrogation zone of at least part of covering toll site (such as back lobe 752 cover part thes lane in which the drivers should pay fees 601).The transponder 613 of the vehicle 621 on the lane in which the drivers should pay fees 601 may be covered the road by the masking signal that antenna element 500 is launched so travel.But, the Fresnel field antenna 300 that antenna element 500 uses back lobe to reduce.As discussed above, the Fresnel field antenna 300 that back lobe reduces uses back lobe Fresnel region reduction means 320, has greatly reduced back lobe Fresnel region 752.For example, for near the ETC system that operates in the 2.5GHz frequency range, the Fresnel region of the Fresnel field antenna 300 that back lobe reduces (is being such zone from about 0.02 meter to 0.8 meter zone, antenna rear surface probably, when vehicle 621 travels on the lane in which the drivers should pay fees 601, when transponder 613 places the right side of vehicle 621, can pass through).According to this concept, use back lobe Fresnel region reduction means structure, above-mentioned masking signal has greatly reduced (greatly reducing to avoid undesirable transponder of covering on vehicle on the lane in which the drivers should pay fees 601 normal mounting of travelling) at this back lobe Fresnel region.Therefore, transponder that vehicle 621 is loaded with 613 wishes to cross the zone of the back lobe 752 that masking signal wherein greatly reduced, so allow correctly interrogator-responder 613 of RF reader 611, and prevented the travel transponder 614 of the vehicle 622 on contiguous track 602 of RF reader 611 inquiries.
Will be appreciated that, although the back lobe Fresnel region reduction means 320 among this embodiment affects the back lobe far-field region hardly, even when transponder 613 is installed in the opposite side (as being installed in vehicle right side rather than the left side at vehicle as shown in Figure 7) of vehicle 621, also wish correctly interrogator-responder of RF reader 611.That is to say, wish that the signal strength signal intensity of the lane in which the drivers should pay fees 601 right-hand component masking signals is very weak (as owing to compare etc. propagation loss, suitable antenna front and back), and wish that the signal strength signal intensity of the lane in which the drivers should pay fees 601 right-hand component request signals is very high.Therefore, the Fresnel field antenna that back lobe reduces is configured to only reduce in the toll site subregion masking signal, otherwise the request signal at this place may be covered by masked signal.
Although in conjunction with the use of ETC system and then described the embodiment of the Fresnel field antenna that back lobe reduces, should be appreciated that the Fresnel field antenna that back lobe reduces can also use in all cases at this.For example, the Fresnel field antenna structure that back lobe reduces can be applied in the wireless network secure enforcement, wherein the Fresnel field antenna that reduces of back lobe is used for providing masking signal to the zone that does not need wireless network communication, and the back lobe Fresnel place that reduces can make things convenient for the wireless network communication of the expectation in other zones.In addition, the Fresnel field antenna structure that reduces of back lobe can be used for PCS Personal Communications System (such as mobile phone, hand-hold wireless transceiver etc.) to reduce the signal radiation to the PCS Personal Communications System user.
Although described the present invention and advantage thereof in detail, should be understood that and to make various changes and replacement to it, and can not break away from the spirit and scope of the invention that is defined by claims.In addition, the scope of the present invention's application is not subject to the specific embodiment of process, machine, manufacturing, material composition, method and the step described in the specification.From disclosure of the present invention, those of ordinary skills will understand easily, can use current existing or following exploitation and can carry out the function identical with said corresponding embodiment or obtain identical result's process, machine, manufacturing, material composition, method or step.Therefore, claims are intended to comprise that these processes, machine, manufacturing, material composition, method and step are in its scope.
Claims (36)
1. antenna comprises:
Antenna element, it has a corresponding main lobe and a back lobe, and wherein said main lobe directional antenna is axial, the direction of described back lobe and described antenna axial direction quadrature; With
Back lobe Fresnel region reduction means, it places in the Fresnel region of described back lobe, and wherein said back lobe Fresnel region reduction means is configured to reduce the Fresnel field signal of described antenna element in described Fresnel region.
2. antenna according to claim 1, wherein said antenna element is a microstrip antenna element.
3. antenna according to claim 1, wherein said back lobe Fresnel region reduction means place on the border between the near-field region of described Fresnel region and described back lobe.
4. antenna according to claim 1, wherein said back lobe Fresnel region reduction means place from described antenna element apart from the d place, d=λ/2 π ± 5% wherein, and wherein λ is the wavelength of the communication carrier of described antenna element.
5. antenna according to claim 1, wherein said antenna element is that a length is the antenna element of D.
6. antenna according to claim 5, wherein said back lobe Fresnel region reduction means place from described antenna element apart from the d place, wherein λ/2 π≤d≤2D
2/ λ, wherein λ is the wavelength of the communication carrier of described antenna element.
7. antenna according to claim 5 also comprises:
The second back lobe Fresnel region reduction means, it places in the Fresnel region of described back lobe.
8. antenna according to claim 7, wherein said back lobe Fresnel region reduction means places on the border between the near-field region of described Fresnel region and described back lobe, wherein said the second back lobe Fresnel region reduction means places from described antenna element apart from the d place, wherein λ/2 π≤d≤2D
2/ λ, wherein λ is the wavelength of the communication carrier of described antenna element.
9. antenna according to claim 1, wherein said back lobe Fresnel region reduction means comprises a conducting plane that is connected with ground.
10. antenna according to claim 9, wherein said back lobe Fresnel region reduction means also comprises: the loss ferrite, in order to reduce the described Fresnel field signal of described antenna element.
11. antenna according to claim 9, wherein said back lobe Fresnel region reduction means also comprises: super material, and in order to reduce the described Fresnel field signal of described antenna element.
12. antenna according to claim 9, wherein said back lobe Fresnel region reduction means also comprises: one or more slits, it places on the described conducting plane, in order to reduce the described Fresnel field signal of described antenna element.
13. antenna according to claim 9 also comprises: signal circuit, it places on the surface of described back lobe Fresnel region reduction means.
14. antenna according to claim 9, wherein said antenna places in the no-stop charging system, provides in order to the request signal to automotive vehicle identification and shelters (masking).
15. a system comprises:
Automotive vehicle identification radio frequency (RF) reader, it is configured to launch request signal and covers a transponder interrogation, an also zone of the contiguous described transponder interrogation of at least part of covering of the described request signal of RF reader wherein, wherein said adjacent domain is such zone, does not wherein expect to use described request signal interrogator-responder;
The Fresnel field antenna that back lobe reduces, it is configured to launch masking signal and covers described adjacent domain, the described masking signal of the Fresnel field antenna that wherein said back lobe reduces also covers the transponder interrogation at least in part, the Fresnel field antenna that wherein said back lobe reduces is configured to reduce the masking signal in the back lobe Fresnel field of the Fresnel field antenna that described back lobe reduces, and therefore alleviates the Fresnel field antenna that reduced by described back lobe the signal of described transponder interrogation is covered.
16. system according to claim 15, the Fresnel field antenna that wherein said back lobe reduces comprises:
Antenna element, it has a corresponding main lobe and a back lobe, wherein said main lobe directional antenna axially and with described masking signal covers described adjacent domain, the direction of wherein said back lobe and described antenna axial direction quadrature, and cover at least in part described transponder interrogation with described masking signal; With
Back lobe Fresnel region reduction means, it places in the Fresnel region of described back lobe, and wherein said back lobe Fresnel region reduction means is configured to reduce the Fresnel field signal of described antenna element in described Fresnel region.
17. system according to claim 16, wherein said antenna element is a microstrip antenna element.
18. system according to claim 16, wherein said back lobe Fresnel region reduction means place on the border between the near-field region of described Fresnel region and described back lobe.
19. system according to claim 16, wherein said back lobe Fresnel region reduction means place from described antenna element apart from the d place, d=λ/2 π ± 5% wherein, and wherein λ is the wavelength of the communication carrier of described antenna element.
20. system according to claim 16, wherein said antenna element is that a length is the antenna element of D.
21. system according to claim 20, wherein said back lobe Fresnel region reduction means place from described antenna element apart from the d place, wherein λ/2 π≤d≤2D
2/ λ, wherein λ is the wavelength of the communication carrier of described antenna element.
22. system according to claim 16, wherein said back lobe Fresnel region reduction means comprises a conducting plane that is connected with ground.
23. system according to claim 22, wherein said back lobe Fresnel region reduction means also comprises: the loss ferrite, and in order to reduce the described Fresnel field signal of described antenna element.
24. system according to claim 22, wherein said back lobe Fresnel region reduction means also comprises: super material, and in order to reduce the described Fresnel field signal of described antenna element.
25. system according to claim 22, wherein said back lobe Fresnel region reduction means also comprises: one or more slits, it places on the described conducting plane, in order to reduce the described Fresnel field signal of described antenna element.
26. system according to claim 22 also comprises: signal circuit, it places on the surface of described back lobe Fresnel region reduction means, and wherein said signal circuit produces described masking signal.
27. system according to claim 15, wherein said automotive vehicle identification RF reader is the part no-stop charging system.
28. a method comprises:
Changing an antenna makes it that back lobe Fresnel region that reduces be arranged, wherein change antenna and comprise a back lobe Fresnel region reduction means is placed in the Fresnel region of wave beam back lobe of antenna element of described antenna that wherein said back lobe Fresnel region reduction means is configured to reduce the Fresnel field signal of described antenna element in described Fresnel region.
29. method according to claim 28 also comprises: provide the loss ferrite in described back lobe Fresnel region reduction means, in order to reduce the described Fresnel field signal of described antenna element.
30. method according to claim 28 also comprises: provide super material in described back lobe Fresnel region reduction means, in order to reduce the described Fresnel field signal of described antenna element.
31. method according to claim 28 also comprises: provide one or more slits in described back lobe Fresnel region reduction means, in order to reduce the described Fresnel field signal of described antenna element.
32. method according to claim 28, wherein said back lobe Fresnel region reduction means comprises a conducting plane that is connected with ground.
33. method according to claim 28 wherein places described back lobe Fresnel region reduction means in the Fresnel region of described wave beam back lobe to comprise: described back lobe Fresnel region reduction means is placed on the border between the near-field region of described Fresnel region and described back lobe.
34. method according to claim 28, wherein described back lobe Fresnel region reduction means is placed in the Fresnel region of described wave beam back lobe and comprise: described back lobe Fresnel region reduction means is placed from described antenna element apart from the d place, d=λ/2 π ± 5% wherein, wherein λ is the wavelength of the communication carrier of described antenna element.
35. method according to claim 28, wherein described back lobe Fresnel region reduction means is placed in the Fresnel region of described wave beam back lobe and comprise: described back lobe Fresnel region reduction means is placed from described antenna element apart from the d place, wherein λ/2 π≤d≤2D
2/ λ, wherein λ is the wavelength of the communication carrier of described antenna element.
36. method according to claim 28 also comprises: utilize described antenna to place in the no-stop charging system, provide in order to the request signal to automotive vehicle identification and shelter (masking).
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US201213648818A | 2012-10-10 | 2012-10-10 | |
| US13/648,818 | 2012-10-10 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103000989A true CN103000989A (en) | 2013-03-27 |
Family
ID=47929287
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012104254309A Pending CN103000989A (en) | 2012-10-10 | 2012-10-30 | Micro-strip antenna with reduced rear lobe of Fresnel zone |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103000989A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107710285A (en) * | 2015-09-30 | 2018-02-16 | 杜拉汽车系统有限公司 | Vehicle enters equipment and the vehicle decorative member equipped with this equipment |
| CN111292532A (en) * | 2020-02-07 | 2020-06-16 | 北京易路行技术有限公司 | Device, communication system and method for detecting vehicle-mounted label on expressway |
| WO2020177025A1 (en) * | 2019-03-01 | 2020-09-10 | Telefonaktiebolaget Lm Ericsson (Publ) | Antenna device and base station comprising the same |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4063246A (en) * | 1976-06-01 | 1977-12-13 | Transco Products, Inc. | Coplanar stripline antenna |
| US20010050651A1 (en) * | 1998-05-28 | 2001-12-13 | Christophe Grangeat | Radiocommunications device, and a slot loop antenna |
| CN102034281A (en) * | 2010-12-10 | 2011-04-27 | 北京快通高速路电子收费系统有限公司 | Method for solving problem of adjacent channel interference through additional antenna positioning |
| CN102299418A (en) * | 2011-06-15 | 2011-12-28 | 集美大学 | Multilayer broadband microstrip antenna |
| CN102299409A (en) * | 2011-05-16 | 2011-12-28 | 电子科技大学 | Broadband dual polarized base station antenna applied to IMT-Advanced system |
-
2012
- 2012-10-30 CN CN2012104254309A patent/CN103000989A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4063246A (en) * | 1976-06-01 | 1977-12-13 | Transco Products, Inc. | Coplanar stripline antenna |
| US20010050651A1 (en) * | 1998-05-28 | 2001-12-13 | Christophe Grangeat | Radiocommunications device, and a slot loop antenna |
| CN102034281A (en) * | 2010-12-10 | 2011-04-27 | 北京快通高速路电子收费系统有限公司 | Method for solving problem of adjacent channel interference through additional antenna positioning |
| CN102299409A (en) * | 2011-05-16 | 2011-12-28 | 电子科技大学 | Broadband dual polarized base station antenna applied to IMT-Advanced system |
| CN102299418A (en) * | 2011-06-15 | 2011-12-28 | 集美大学 | Multilayer broadband microstrip antenna |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107710285A (en) * | 2015-09-30 | 2018-02-16 | 杜拉汽车系统有限公司 | Vehicle enters equipment and the vehicle decorative member equipped with this equipment |
| WO2020177025A1 (en) * | 2019-03-01 | 2020-09-10 | Telefonaktiebolaget Lm Ericsson (Publ) | Antenna device and base station comprising the same |
| US11778486B2 (en) | 2019-03-01 | 2023-10-03 | Telefonaktiebolagget LM Ericsson (Publ) | Antenna device and base station comprising the same |
| CN111292532A (en) * | 2020-02-07 | 2020-06-16 | 北京易路行技术有限公司 | Device, communication system and method for detecting vehicle-mounted label on expressway |
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Application publication date: 20130327 |