CN106252872B - Co-polarized microstrip duplex antenna array - Google Patents

Abstract

The invention discloses a co-polarized microstrip duplex antenna array, which comprises two identical symmetrically placed microstrip patch antennas and an anti-phase power distribution network with a duplex function, the anti-phase power distribution network Including power distribution microstrip line, transmitting microstrip band-rejection filter, transmitting impedance conversion microstrip line, receiving microstrip band-rejection filter and receiving impedance conversion microstrip line; one end of the transmitting microstrip band-rejection filter is connected to the transmitting port , the other end is connected to the power distribution microstrip line through the transmission impedance transformation microstrip line; one end of the reception microstrip band-stop filter is connected to the receiving port, and the other end is connected to the power distribution microstrip line through the reception impedance transformation microstrip line. The present invention designs a duplex power distribution network with both duplex function and power distribution function. The structure of the antenna is relatively compact and the gain is high. At the same time, high isolation between the sending and receiving ports is realized by setting the sending and receiving microstrip band-stop filters.

Description

Co-polarized Microstrip Duplex Antenna Array

technical field

The invention belongs to the technical field of wireless communication, in particular to a co-polarized microstrip duplex antenna array.

Background technique

The antenna feeder system is the front end of the wireless communication system and an indispensable key component of the wireless communication system. The antenna feed system includes antenna, filter and duplexer. The traditional method is to design the three separately and connect them with radio frequency cables. The disadvantage is that all three need a separate matching network to match the 50 ohm feeder, which brings about the problems of large volume and total weight. At the same time, too many matching networks bring about the disadvantage of large loss.

With the development of wireless communication, the communication system tends to be miniaturized and integrated more and more. Therefore, there is a great demand for an integrated antenna-feeder system. Duplex antennas combine antennas, filters, duplexers and other front-end components to make the structure of the RF front-end system more compact, reduce unnecessary loss, and make the miniaturization and integration of the communication system easier to achieve.

In the existing technology, antennas capable of duplexing (transmitting and receiving signals at the same time) are mainly dual-polarized antennas. This type of antenna adopts different polarization modes for transmitting and receiving signals, and the transmission and reception of the antenna can work on the same frequency band or different frequency bands. However, in most communication systems, transmission and reception are often required to be of the same polarization, and the radiation patterns of transmission and reception are required to be as consistent as possible. Therefore, it is necessary to develop a co-polarized duplex antenna.

At present, the design of co-polarized duplex antenna mainly utilizes microstrip patch or slot structure to radiate two modes of the same polarization. Through the isolation between modes, or adding a resonant structure to the feed network to form a filter antenna with the radiation structure, the port isolation between two co-polarized operating frequencies can be achieved. Currently proposed co-polarization duplex antennas have relatively large intervals between transmitting and receiving frequencies, port isolation is generally between 20-30dB, and antenna gain is below 5dBi. Therefore, the current co-polarized duplex antennas generally have the disadvantages of low port isolation, a relatively large interval between transmitting and receiving frequencies of the antenna, and low gain of the antenna.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art, and provide a co-polarized microstrip duplex antenna array. Compared with the existing co-polarized duplex antenna, the transmission and reception frequency intervals of the antenna are closer, The port isolation of the antenna for transmitting and receiving is high, and the gain of the antenna is high.

The purpose of the present invention is achieved through the following technical solutions: co-polarized microstrip duplex antenna array, including two identical microstrip patch antennas placed symmetrically and a reversed-phase power distribution network with duplex function, said The reverse-phase power distribution network includes a power distribution microstrip line, a transmission microstrip band-stop filter, a transmission impedance conversion microstrip line, a receiving microstrip band-stop filter and a receiving impedance conversion microstrip line; the transmission microstrip band-stop filter One end is connected to the transmitting port, and the other end is connected to the power distribution microstrip line through the transmitting impedance transformation microstrip line; one end of the receiving microstrip band-stop filter is connected to the receiving port, and the other end is connected to the power distribution microstrip line through the receiving impedance transformation microstrip line. Connected with wire.

Preferably, the transmitting microstrip bandstop filter is connected to the power distribution microstrip line at a distance of _λg /4 from the central point of the power distribution microstrip line through the transmission impedance transformation microstrip line, and λg _is the transmission signal at the power Assign wavelengths on the microstrip line.

Preferably, the receiving microstrip bandstop filter is connected to the power distribution microstrip line on the other side of the center point of the power distribution microstrip line through the receiving impedance transformation microstrip line and at a distance _{of λg} /4 from the center point, λ _{g is received} as the wavelength of the received signal on the power distribution microstrip line.

Specifically, the co-polarized microstrip duplex antenna array also includes two parallel upper dielectric substrates and lower dielectric substrates, the upper surface of the lower dielectric substrate is covered with a metal reflective floor, and the bottom surface is provided with an anti-phase power distribution network The microstrip patch antenna includes two rectangular metal patches printed on the upper surface of the upper dielectric substrate and the T-shaped probe for exciting the microstrip patch antenna, and the T-shaped probe is printed on the metal microstrip on the surface of the upper dielectric substrate. The metal probe is connected to the center of the metal microstrip, and the other end of the metal probe is respectively connected to the two ends of the power distribution microstrip line through the reflection floor and the through hole on the lower dielectric substrate.

Preferably, the transmitting microstrip bandstop filter is composed of two open-ended microstrip lines and a connecting microstrip line. The length and width of the stripline are such that the _transmitted signal at frequency f can pass but the _received signal at frequency f cannot pass.

Preferably, the receiving microstrip bandstop filter is composed of two sections of open-ended microstrip lines and a section of connecting microstrip lines, the two ends of the connecting microstrip lines are respectively connected with two end-opening microstrip lines, the end-opening microstrip lines and the connecting microstrip line The length and width of the stripline are such that the _received signal at frequency f can pass through, but the _transmitted signal at frequency f cannot pass through.

Furthermore, the operating passband and stopband frequencies of the transmitting microstrip bandstop filter and the receiving microstrip bandstop filter are opposite.

Preferably, the length and width of the transmission impedance transformation microstrip line meet the following requirements: to ensure that for the _received signal at a frequency of f, when the transmission port is connected to a matched load, the impedance of the connection end of the power distribution microstrip line is close to an open circuit . Thus, the transmission of the _received signal at the frequency f on the power distribution microstrip line is not affected.

Preferably, the length and width of the receiving impedance transformation microstrip line meet the following requirements: to ensure that for the transmission signal with a frequency of f, when the _receiving port is connected to a matching load, the impedance of the connection end of the power distribution microstrip line is close to an open circuit . Therefore, the transmission of the _transmitted signal with the frequency f on the power distribution microstrip line is not affected.

Furthermore, the transmitting impedance transforming microstrip line and the receiving impedance transforming microstrip line are left and right sections of 50Ω impedance transforming lines with lengths of λ _{g receiving} /4 and λ _{g sending} /4 working at different frequencies.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The present invention combines the power distribution network of the array antenna with the duplex network design, and designs a duplex power distribution network with both duplex function and power distribution function. Therefore, the structure of the antenna is relatively compact. At the same time, the high isolation between the sending and receiving ports is realized by setting the sending microstrip band-stop filter at the sending port and the receiving microstrip band-stop filter at the receiving port. At the same time, the invention improves the gain of the antenna by designing the antenna array.

2. The signals transmitted and received by the present invention are coupled with the patch antenna through the microstrip on the T-type probe, and its polarization direction is the same as that of the coupled microstrip, realizing the same polarization for transmission and reception.

3. The present invention transmits and receives little mutual interference. By inserting a transmission impedance conversion microstrip line between the transmission microstrip band-rejection filter and the power distribution microstrip line, the transmission branch will not generate a signal on the received signal on the power distribution microstrip line. Influence. By inserting the receiving impedance conversion microstrip line between the receiving microstrip band-stop filter and the power distribution microstrip line, it is possible to make the receiving branch not affect the transmission on the power distribution microstrip line when the transmitting port (port 1) is working. Signals have an impact. Therefore, the mutual interference between transmission and reception is small.

4. Existing co-polarized duplex antennas are usually designed based on the design method of band-pass filters, while the pass-band of band-pass filters is more concerned with the design within the pass-band, and outside the band that is relatively close to the pass-band , the effect of suppressing the passage of signals is generally not very good, so the frequency interval of sending and receiving is generally far away to obtain better port isolation. However, the present invention adopts the method of band-rejection filter to design the co-polarization duplex antenna, which has a better effect of suppressing the passing of signals outside the pass-band, so it can realize a relatively small sending and receiving frequency interval, and keep Better transmission and reception isolation characteristics.

Description of drawings

Fig. 1 is the general schematic diagram of the present embodiment and the numbering label of main components;

Fig. 2 is the overall schematic diagram of the present embodiment and the numbering labeling of refinement;

Fig. 3 is the front sectional view of the antenna of this embodiment;

FIG. 4 is a top view of the upper dielectric substrate of this embodiment;

FIG. 5 is a bottom view of the upper dielectric substrate of this embodiment;

FIG. 6 is a top view of the lower dielectric substrate in this embodiment;

FIG. 7 is a bottom view of the lower dielectric substrate of this embodiment;

FIG. 8 is a dimensional drawing of the upper surface structure of the upper dielectric substrate in this embodiment;

FIG. 9 is a dimensional drawing of the lower surface structure of the upper dielectric substrate in this embodiment;

FIG. 10 is a dimensional drawing of the upper surface structure of the lower dielectric substrate in this embodiment;

Fig. 11 is the simulation S-parameter curve diagram of the embodiment sending the band-stop filter example;

Fig. 12 is the simulation S-parameter curve diagram of the receiving bandstop filter example of the present embodiment;

Fig. 13 is the simulation S parameter of transmitting and transforming the microstrip line connected to transmitting the microstrip bandstop filter of the present embodiment, and the impedance diagram after the transmitting port (port 1) is connected to the matching load;

Fig. 14 is the simulation S parameter of receiving transformed microstrip line connection receiving microstrip band-stop filter of the present embodiment and the impedance diagram after the receiving port (port 2) is connected to the matched load;

Fig. 15 is the test S parameter curve diagram of the antenna of the present embodiment;

Fig. 16 (a) is the E plane test pattern of the excitation of the antenna port 2 (2.2GHz) of the present embodiment;

Fig. 16 (b) is the H surface test pattern of the excitation of the antenna port 2 (2.2GHz) of the present embodiment;

Fig. 17 (a) is the E plane test pattern of the excitation of the antenna port 1 (2.4GHz) of the present embodiment;

Fig. 17 (b) is the H plane test pattern of the excitation of the antenna port 1 (2.4GHz) of the present embodiment;

FIG. 18 is a curve of test gain versus frequency of the antenna of this embodiment.

Detailed ways

The present invention will be further described in detail below in conjunction with the embodiments and the accompanying drawings, but the embodiments of the present invention are not limited thereto.

With reference to Fig. 1, Fig. 2 and Fig. 3, the co-polarized microstrip duplex antenna array of this embodiment includes two identical microstrip patch antennas 1 placed symmetrically and a reversed-phase power distribution network with a duplex function 2. The inverting power distribution network 2 includes a power distribution microstrip line 3, a transmission microstrip band-stop filter 4, a transmission impedance conversion microstrip line 6, a reception microstrip band-stop filter 5 and a reception impedance conversion microstrip line 7.

One end of the sending microstrip bandstop filter 4 is connected to the sending port (port 1), and the other end passes through the sending impedance transformation microstrip line 6 and the power distribution microstrip line 3 at a distance from the center point of the power distribution microstrip line _λg /4 λ _{g is} the wavelength of the transmitted signal on the power distribution microstrip line 3 .

One end of the receiving microstrip band-stop filter 5 is connected to the receiving port (port 2), and the other end passes through the receiving impedance transformation microstrip line 7 and the power distribution microstrip line 3 on the other side of the center point of the power distribution microstrip line The center point λ _g is connected to /4, and λ _{g is} the wavelength of the received signal on the power distribution microstrip line 3 .

The transmitting impedance transforming microstrip line 6 and the receiving impedance transforming microstrip line 7 are 50Ω impedance transforming lines with the lengths of λ _{g receiving} /4 and λ _{g sending} /4 and working at different frequencies. The microstrip impedance transformation lines 6, 7 are followed by two sections of low-impedance transmission lines 21, 22 respectively, and then connected to two ports of the radio frequency system through two sections of 50Ω transmission lines 25, 26. Four loaded L-shaped terminal open-circuit stub lines 19, 20, 23, 24 are respectively loaded on the two ends of two low-impedance lines 21, 22, and the two low-impedance lines form two band-stop filters at the transmitting and receiving ports . The working passband and stopband frequencies of the two bandstop filters are just opposite.

The transmitting microstrip bandstop filter 4 is composed of two sections of open-ended microstrip lines 19 and 23 and a section of connecting microstrip line 21, and two open-circuit microstrip lines 19 and 23 are respectively connected to the two ends of the connecting microstrip line 21. The length and width of the open-ended microstrip lines 19, 23 and the connecting microstrip line 21 are properly selected so that the _transmitted signal at frequency f can pass through, while the _received signal at frequency f cannot pass through. As an example, when requiring f _{to send out} =2.4GHz, f _receives =2.2GHz, can adopt relative permittivity to be 2.55, the dielectric plate that thickness is h=0.8mm is made substrate, the length of open-circuit microstrip line 19 gets 25.7mm , the width is 0.5mm, the length of the open microstrip line 23 is 26.5mm, the width is 0.5mm, the length of the connecting microstrip line 21 is 25.7mm, and the width is 7mm. Figure 11 is the sending microstrip bandstop filter at this time It can be seen that its S12 is -1.94dB when the frequency is 2.4GHz, and its S12 is -35.45dB when the frequency is 2.2GHz, which realizes the function of blocking the receiving signal by sending the signal.

The receiving microstrip bandstop filter 5 is composed of two sections of open-ended microstrip lines 20 and 24 and a section of connecting microstrip line 22, and two open-circuit microstrip lines 20 and 24 are respectively connected to the two ends of the connecting microstrip line 22. The length and width of the open-ended microstrip lines 20, 24 and the connecting microstrip line 22 are properly selected so that the _received signal at frequency f can pass through, while the _transmitted signal at frequency f cannot pass through. As an example, when requiring f _{to send out} =2.4GHz, f _receives =2.2GHz, can adopt the dielectric plate that relative permittivity is 2.55, thickness is h=0.8mm to do substrate, the length of open-circuit microstrip line 20 gets 26.5mm , the width is 0.5mm, the length of the open circuit microstrip line 24 is 25.9mm, and the width is 0.5mm, the length of the connecting microstrip line 22 is 25.5mm, and the width is 13mm. Figure 12 is the receiving microstrip bandstop filter at this time It can be seen that its S12 is -1.22dB when the frequency is 2.2GHz, and its S12 is -38.07dB when the frequency is 2.4GHz, which realizes the function of blocking the sending signal by receiving the signal.

Transmitting impedance transforming microstrip line 6 ensures that for the _received signal with frequency f, its impedance (transmitting port (port No. 1)) at the connection end of power distribution microstrip line 3 is matched by properly selecting its length and width. load) is very large (close to an open circuit), so as not to affect the transmission of the _received signal at the frequency f on the power distribution microstrip line 3 . As an example, when requiring f _{to send} =2.4GHz, f _{to receive} =2.2GHz, can adopt relative permittivity to be 2.55, the dielectric plate that thickness is h=0.8mm is made substrate, and the length of transmitting impedance transformation microstrip line 6 is taken as 24mm, the width is 2.25mm, and the above-mentioned example of transmitting microstrip bandstop filter is connected, its S parameters, and the impedance of the transmitting port (port 1) connected to the matching load are shown in Figure 13. It can be seen that the impedance is greater than 1000 ohms when f _receive = 2.2 GHz, and the attenuation is very little for the transmit signal with frequency f _transmit = 2.4 GHz.

The receiving impedance transformation microstrip line 7 ensures that for the _transmission signal with frequency f, its impedance at the connection end with the power distribution microstrip line 3 (the receiving port (port 2) is connected to the matching load by selecting its length and width appropriately) ) is very large (close to an open circuit), so that it does not affect the transmission of the _transmitted signal at the frequency f on the power distribution microstrip line 3 . As an example, when f _sends =2.4GHz, and f _receives =2.2GHz, can adopt relative permittivity to be 2.55, the dielectric plate that thickness is h=0.8mm is made substrate, and the length of receiving impedance conversion microstrip line 7 gets 20mm, The width is 2.25mm, and the above-mentioned example of receiving microstrip band-stop filter is connected. The S parameters and the impedance of the receiving port (port 2) connected to the matching load are shown in Figure 14. It can be seen that when f = _2.4GHz , the impedance is greater than 1000 ohms, and the attenuation is very little for the received signal with frequency f = _2.2GHz .

The co-polarized microstrip duplex antenna array also includes two parallel upper layer dielectric substrates 8 and lower layer dielectric substrates 10, the upper surface of the lower layer dielectric substrate 10 is covered with a metal reflection floor 9, and the bottom surface is provided with a reflector of the antenna. Phase power distribution network 2.

The microstrip patch antenna 1 includes two rectangular metal patches 11 and 12 printed on the upper surface of the upper dielectric substrate 8 and a T-shaped probe for exciting the microstrip patch antenna. The T-shaped probe is composed of metal microstrips 13, 14 printed on the lower surface of the upper dielectric substrate 8 and metal probes 15, 16 connected to the center of the metal microstrips 13, 14. The other ends of the metal probes 15, 16 are The two ends of the power distribution microstrip line 3 pass through the through holes 17 and 18 on the reflective floor 9 and the lower dielectric substrate 10 respectively.

When sending, the sending signal is sent from the sending port (port 1), and sent to the power distribution microstrip line through the sending microstrip band-rejection filter 4 and the sending impedance transformation microstrip line 6. The signal passing through the power distribution microstrip line is distributed to two T-shaped probes 13, 14, 15, and 16 with the same amplitude and opposite phase (phase difference of 180 degrees), and passes through the microstrip on the T-shaped probe. The strips 13 , 14 are coupled to radiating patches 11 , 12 . Since the two patches 11, 12 are symmetrically placed and excited, the electromagnetic waves coupled through the microstrip 13, 14 will generate a phase difference of 180 degrees at the two patches again, so that the signal phases of the two radiating patches radiate 11, 12 Similarly, they can be superimposed in the same direction in the positive Z direction of the antenna, resulting in higher antenna gain. The polarization direction of the electromagnetic wave radiated by the antenna is the same as the direction of the long sides of the coupling microstrips 13 and 14 .

When receiving, received signals are received from the two radiating patch antennas 11 , 12 and coupled to T-probes 13 , 14 , 15 , 16 . The polarization direction of the received electromagnetic wave is the same as that of the long sides of the coupling microstrips 13 and 14 . The received signal is sent to both ends of the power distribution microstrip line 3 after passing through T-shaped probes 13 , 14 , 15 , and 16 . At this time, the signals at both ends of the power distribution microstrip line 3 are also equal in amplitude and 180 degrees out of phase. The signals at both ends of the power distribution microstrip line 3 respectively pass through the power distribution microstrip line with a phase of 180 degrees and arrive at the receiving impedance transformation microstrip line 7. They are just superimposed with the same phase, and then pass through the receiving impedance transformation microstrip line 7 and the receiving microstrip line. Rejection filter 5, output from the receiving port (port 2).

Figures 4, 5, 6, and 7 are the electrical structure diagrams of the upper and lower surfaces of the two dielectric substrates respectively. The stripe filling part is the structure covered by conductor copper, and the rest is the dielectric substrate.

Figures 8, 9, and 10 are dimensioned diagrams of the electrical structure of each part.

Combined with the dimensions in Figure 2, Figure 8, Figure 9, and Figure 10, the specific parameters of the antenna in this embodiment are as follows: both dielectric plates are FR4 plates, the thickness c is 0.8mm, the width b is 130mm, and the length a is 200mm . The height h between the two dielectric plates is 6mm. The side lengths 1a and 1b of the rectangular patch are 49mm and 50mm respectively, and the distance 1c is 49.5mm. The two elongated microstrips used for coupling are 2a long, 2b wide, and the spacing 2c is 2mm, 6.5mm, and 69.5mm, respectively. The power distribution network is left-right symmetrical, and its main dimensions 3a, 4a, 5a, 6a, 3b are 28.5mm, 21.78mm, 22.73mm, 27.3mm, 1.27mm respectively. The lengths 7a and 8a of the two 50Ω impedance transformation lines are 24mm and 20mm respectively, and the width 7b is 2.25mm. The width 4b of the four open-ended L-shaped stub lines is 0.5mm, and the lengths 9a, 10a, 13a, and 14a are 25.7mm, 26.5mm, 26.5mm, and 25.9mm, respectively. The lengths 11a, 12a and widths 5b, 6b of the two sections of low-impedance transmission are 25.7mm, 25.5mm, 7mm, and 13mm, respectively. The lengths of the two transmission lines connected to the port are 28.83mm, 33.03mm, and the width is 2.25mm respectively. Port 1 of the antenna works in a frequency band of 2.4 GHz and serves as a sending port. Port 2 works in the 2.2GHz frequency band as a receiving port. In the two frequency bands, the isolation of the two ports is greater than 33dB, as shown in Figure 15. In the two operating frequency bands, the gain of the antenna is basically greater than 9.5dBi, and the cross-polarization is greater than 20dB, as shown in the simulation test patterns 16 and 17 of the antenna. When the port 2 of the antenna is working, the gain of the antenna at the port 2 operating frequency of 2.2GHz is 10dBi, while the gain at the port 1 operating frequency of 2.4GHz drops rapidly to below -25dBi, and the gain difference reaches more than 30dB, as shown in the figure 18. Similarly, when the port 1 of the antenna is working, the gain of the antenna at the port 1 operating frequency of 2.4GHz is 9.8dBi, while the gain of the port 2 operating frequency of 2.2GHz also drops rapidly to below -25dBi, and the gain difference reaches 30dB Above, as shown in Figure 18. This side proves that the duplex antenna has a high port isolation between the two ports.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (9)

1. The co-polarization microstrip duplex antenna array is characterized by comprising two identical microstrip patch antennas which are symmetrically arranged and an inverted power distribution network with a duplex function, wherein the inverted power distribution network comprises a power distribution microstrip line, a sending microstrip band elimination filter, a sending impedance conversion microstrip line, a receiving microstrip band elimination filter and a receiving impedance conversion microstrip line; one end of the sending microstrip band elimination filter is connected with the sending port, and the other end of the sending microstrip band elimination filter is connected with the power distribution microstrip line through the sending impedance transformation microstrip line; one end of the receiving microstrip band elimination filter is connected with the receiving port, and the other end of the receiving microstrip band elimination filter is connected with the power distribution microstrip line through the receiving impedance transformation microstrip line;

the co-polarization microstrip duplex antenna array further comprises an upper dielectric substrate and a lower dielectric substrate which are arranged in parallel, the upper surface of the lower dielectric substrate is covered with a metal reflecting floor, and the bottom surface of the lower dielectric substrate is provided with an inverse power distribution network; the microstrip patch antenna comprises two rectangular metal patches printed on the upper surface of an upper-layer dielectric substrate and a T-shaped probe for exciting the microstrip patch antenna, wherein the T-shaped probe consists of a metal microstrip printed on the surface of the upper-layer dielectric substrate and a metal probe connected to the center of the metal microstrip, and the other end of the metal probe penetrates through holes in a reflection floor and a lower-layer dielectric substrate respectively and is connected with two ends of a power distribution microstrip line.

2. The co-polarized microstrip duplex antenna array of claim 1 wherein the transmit microstrip band reject filter is configured to pass the transmit impedance transformation microstrip line and the power distribution microstrip line at a distance λ from a center point of the power distribution microstrip line _{g hair} At position/4 is connected, λ _{g hair} The wavelength of the sending signal on the power distribution microstrip line.

3. The co-polarized microstrip duplex antenna array as claimed in claim 1, wherein the receive microstrip band reject filter passes through the receive impedance transformation microstrip line and the power distribution microstrip line on the other side of the center point of the power distribution microstrip line and λ from the center point _{g harvesting} At position/4 is connected, λ _{g harvesting} The wavelength of the received signal on the power distribution microstrip line.

4. The co-polarized microstrip duplex antenna array according to claim 1 or 2, wherein the transmitting microstrip band stop filter is composed of two end open-circuited microstrip lines and a connecting microstrip line, the two ends of the connecting microstrip line are respectively connected to the two end open-circuited microstrip lines, and the lengths and widths of the end open-circuited microstrip line and the connecting microstrip line are such that the frequency is f _{Hair-like device} Can pass through the transmission signal of (f) _{Harvesting machine} Cannot pass through.

5. The co-polarized microstrip duplex antenna array as claimed in claim 1 or 3, wherein the receiving microstrip band stop filter is composed of two sections of open-ended microstrip lines at the ends and one section of connecting microstrip line at the endsRespectively connected with two open-circuit microstrip lines at the tail ends, wherein the length and the width of the open-circuit microstrip line at the tail end and the connection microstrip line enable the frequency to be f _{Harvesting machine} Can pass through a received signal of frequency f _{Hair-like device} Cannot pass the transmission signal of (1).

6. The co-polarized microstrip duplex antenna array as claimed in claim 1, wherein the operational pass band of the transmit microstrip band stop filter and the receive microstrip band stop filter are opposite to the stop band frequency.

7. The co-polarized microstrip duplex antenna array of claim 1 wherein the length and width of the transmit impedance transformation microstrip line meet the following requirements: ensuring for a frequency f _{Harvesting machine} When the transmission port is connected to the matching load, the impedance of the connection terminal to the power distribution microstrip line approaches an open circuit.

8. The co-polarized microstrip duplex antenna array of claim 1 wherein the length and width of the receive impedance transforming microstrip line meet the following requirements: ensuring for a frequency f _{Hair-like device} When the receiving port is connected to the matching load, the impedance of the connection end with the power distribution microstrip line approaches an open circuit.

9. The co-polarized microstrip duplex antenna array of claim 1 wherein the transmit and receive impedance transformation microstrip lines are such that the two left and right center points of the power distribution microstrip line operate at different frequencies with a length λ _{g receive} A/4 and lambda _{g hair} A 50 Ω impedance transformation line of/4.

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