A broadband high-isolation antenna array with the same circular polarization for transmission and reception

Abstract

The present invention provides a broadband, high-isolation antenna array with identical circular polarization for both transmission and reception, belonging to the field of microwave antenna technology. The array comprises eight radiating elements arranged in a crisscross pattern, with four radiating elements forming a group, for a total of two groups with identical circular polarization. The array achieves high isolation and identical circular polarization across a wide frequency band, and is suitable for use in co-frequency, simultaneous full-duplex systems and other microwave communication systems.

Description

Technical Field

[0001] The present invention belongs to the technical field of microwave antennas, and in particular relates to a differentially fed broadband high-isolation antenna array with co-directional circular polarization for transmission and reception. Background Art

[0002] Antennas, as basic devices for receiving and transmitting radio waves, are an essential component of wireless communication systems. Circularly polarized antennas are commonly used in vehicular communication systems, airborne communications, and satellite communications. With the explosive growth in demand for information and data exchange, and the emergence of advanced applications based on massive multiple-input multiple-output (MIMO) and indoor directional wireless power transmission systems, the use of multi-port antennas for both transmission (Tx) and reception (Rx) offers significant advantages, especially when considering the size and possible compactness of the antenna system. For such applications, improving isolation between ports remains a critical and challenging problem. Therefore, achieving broadband, high-isolation circularly polarized antenna arrays in a limited space has become a challenge in current wireless communications.

[0003] The paper "Dual-circularly polarized patch antenna using simple isolation techniques and its array application, (PL Bihan, Y. Zhaksylyk, PDHRe, SK Podilchak, M. García-Vigueras, and G. Goussetis, 12th European Conference on Antennas and Propagation (EuCAP 2018), 2018, pp. 1-5)" proposes a simple and low-cost aperture-coupled circularly polarized antenna. This antenna uses slot feeding to cancel surface currents in a specific area of ​​the antenna. However, this solution suffers from low port isolation and difficulty expanding to more operating frequency bands.

[0004] The paper "Monostatic Co-Polarized Full-Duplex Antenna with Left or Right-Hand Circular Polarization (Jaegeun Ha, Mohamed A. Elmansouri, PrathapValaleprasannakumar. IEEE Transactions on Antennas and Propagation, 2017:10.1109)" proposes a high-isolation circularly polarized antenna based on a beamforming network. This antenna achieves port isolation of at least 47 dB in the 2.4-2.5 GHz frequency band, but its structure is not conducive to miniaturization and integration, and it is difficult to further expand the bandwidth.

[0005] The paper "Dual-Band and Dual-Circularly Polarized Single-Layer Microstrip Array Based on Multiresonant Modes (Jin-Dong Zhang, Lei Zhu, Neng-Wu Liu, WenWu, IEEE Transactions on Antennas and Propagation, 2017:1428-1433)" proposes a circularly polarized antenna based on a thin single-layer substrate and a planar cross-junction. This antenna's port isolation needs to be further improved in the 2.4 GHz WLAN band, and structural limitations make it difficult to apply to more frequency bands.

[0006] Currently, relevant research has reported high-isolation dual-circularly polarized antennas. However, these reports generally lack port isolation or have too narrow an operating band, making their implementation methods inapplicable to other frequency bands. Therefore, realizing a broadband, high-isolation dual-circularly polarized antenna array is a challenging and important topic in the field of microwave antenna technology. Summary of the Invention

[0007] In view of this, the present invention provides a broadband high-isolation antenna with the same circular polarization for transmission and reception, which has the advantages of wide bandwidth, high isolation and easy implementation.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] A broadband high-isolation antenna array for transmitting and receiving signals with the same circular polarization, comprising a first dielectric plate, a perforated floor plate, a second dielectric plate, and a third dielectric plate arranged from bottom to top. A first feed network is provided on the back of the first dielectric plate, and a second feed network and a radiation patch are provided on the front of the second dielectric plate. The first feed network and the second feed network together constitute a feed network structure. A parasitic patch is provided on the back of the third dielectric plate.

[0010] The radiation patch is divided into eight radiation units, all of which operate in a linear polarization mode. The eight radiation units are numbered from small to large in a crisscross pattern, wherein the first, third, fifth, and seventh radiation units constitute a first radiation unit group; the second, fourth, sixth, and eighth radiation units constitute a second radiation unit group; and the eight parasitic patches are respectively located directly above the eight radiation units.

[0011] The feeding network structure has two input ports and sixteen output ports, providing equal-amplitude but unequal-phase feeding to eight radiating elements; the first input port of the first feeding network corresponds to the first, fourth, fifth, eighth, ninth, twelfth, thirteenth and sixteenth feed sources at the output ports; the second input port of the second feeding network corresponds to the second, third, sixth, seventh, tenth, eleventh, fourteenth and fifteenth feed sources at the output ports;

[0012] The first radiating element is excited by the first or second feed source, the second radiating element is excited by the third or fourth feed source, the third radiating element is excited by the fifth or sixth feed source, the fourth radiating element is excited by the seventh or eighth feed source, the fifth radiating element is excited by the ninth or tenth feed source, the sixth radiating element is excited by the eleventh or twelfth feed source, the seventh radiating element is excited by the thirteenth or fourteenth feed source, and the eighth radiating element is excited by the fifteenth or sixteenth feed source.

[0013] Furthermore, the first to sixteenth feed sources are excited with equal amplitudes, and the excitation phases of the first, fifth, ninth, and thirteenth feed sources are reduced by 90° in sequence. o The excitation phase of the twelfth feed source is the same as that of the first feed source, and the excitation phases of the twelfth, sixteenth, fourth, and eighth feed sources decrease by 90 degrees respectively. o The excitation phase of the second, sixth, tenth and fourteenth feed sources decreases by 90 degrees respectively. o The excitation phase of the third feed source is the same as that of the second feed source, and the excitation phases of the third, seventh, eleventh, and fifteenth feed sources decrease by 90 degrees respectively. o .

[0014] Furthermore, the eight radiation units have the same structure.

[0015] Furthermore, the first radiation unit group and the second radiation unit group are both left-hand circularly polarized.

[0016] Furthermore, the feeding network offsets the residual signal between ports through a differential network and a broadband phase shifting network, and includes a first excitation source, a second excitation source, a first differential network, a second differential network, a first phase shifter, a second phase shifter, a third phase shifter, a fourth phase shifter, a fifth phase shifter, a sixth phase shifter, a seventh phase shifter, and an eighth phase shifter;

[0017] The first excitation source located on the back of the first dielectric plate is subjected to equal amplitude and anti-phase power distribution through the first differential network to obtain the first and second paths; the first path is subjected to equal power distribution of one-to-two paths to obtain the third and fourth paths; the third path is connected to the front of the second dielectric plate through a metal column and then subjected to equal power distribution of one-to-two paths to obtain the fifth and sixth paths; the fifth path is subjected to 90° rotation through the first phase shifter o Phase shift, connected to the sixteenth feed, the sixth feed is connected to the first feed; the fourth feed is 90 degrees through the second phase shifter o Phase shifting, after phase shifting, is connected to the front of the second dielectric plate through a metal column, and then divided into two equal power distributions to obtain the seventh and eighth channels; the seventh channel is 90 degrees through the third phase shifter o Phase shifting is performed and connected to the fourth feed source, and the eighth channel is connected to the fifth feed source; the second channel is divided into two equal power channels to obtain the ninth and tenth channels; the ninth channel is connected to the front of the second dielectric plate through a metal column and then divided into two equal power channels to obtain the eleventh and twelfth channels; the eleventh channel is divided into two equal power channels by 90° through the fourth phase shifter. o Phase shift, after phase shift, connected to the eighth feed, the twelfth route connected to the ninth feed; the tenth route is 90 degrees through the fifth phase shifter o Phase shifting, after phase shifting, is connected to the front of the second dielectric plate through a metal column, and then divided into two equal power distributions to obtain the 13th and 14th paths; the 13th path is 90 degrees through the sixth phase shifter o Phase shift, after phase shifting, connected to the 13th feed, and the 14th channel connected to the 13th feed;

[0018] The second excitation source located on the back of the first dielectric plate performs equal amplitude reverse power distribution through the second differential network to obtain the fifteenth and sixteenth paths; the fifteenth path is connected to the front of the second dielectric plate through a metal column, and then performs one-to-two equal power distribution to obtain the seventeenth and eighteenth paths; the seventeenth path performs one-to-two equal power distribution and is connected to the fourteenth and fifteenth feed sources respectively; the eighteenth path is 90° through the seventh phase shifter o Phase shifting, and then one-to-two equal power distribution, respectively connected to the second feed and the third feed; the sixteenth channel is connected to the front of the second dielectric plate through a metal column, and then one-to-two equal power distribution is performed to obtain the nineteenth and twentieth channels; the nineteenth channel is subjected to one-to-two equal power distribution and connected to the sixth feed and the seventh feed respectively; the twentieth channel is 90° through the eighth phase shifter oPhase shifting is performed, and then equal power distribution is performed into two paths, which are connected to the tenth feed and the eleventh feed respectively.

[0019] The beneficial effects of the present invention are:

[0020] The broadband, high-isolation antenna array designed for transmitting and receiving the same circular polarization includes radiating elements and a dual-circularly polarized feed network. It generates circularly polarized waves using two groups of four elements in a sequentially rotated sequence. The feed network utilizes a microstrip structure, providing each radiating element with the amplitude and phase required for circular polarization via a differential network and a broadband phase-shifting network. The entire antenna design and structure can be implemented using a multi-layer PCB process.

[0021] Compared with the existing technology, the present invention achieves a working bandwidth of 10.3%, the working frequency covers 5.5GHz~6.1GHz, the in-band reflection coefficient is less than -10dB, the transmit-receive isolation is greater than 50dB, and the circular polarization axis ratio is less than 3dB; it has the advantages of wide bandwidth, high isolation, and easy implementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the overall structure of a broadband high-isolation antenna array in an embodiment of the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the layout of the medium radiation patch array;

[0024] Figure 3 is a schematic structural diagram of a first feeding network;

[0025] Figure 4 is a schematic structural diagram of a second feeding network;

[0026] Figure 5 A schematic structural diagram of a connecting metal column between a first dielectric plate and a second dielectric plate;

[0027] Figure 6 The figure is a schematic diagram of the overall structure of the feed network structure; the left side is the first feed network, and the right side is the second feed network;

[0028] Figure 7 for Figure 6 Schematic diagram of the structure of the medium-wideband phase-shifting network;

[0029] Figure 8 for Figure 6 Schematic diagram of the differential network structure;

[0030] Figure 9 Graph showing echo characteristics of a broadband high-isolation antenna array according to an embodiment of the present invention;

[0031] Figure 101 is an axial ratio characteristic diagram of a broadband high isolation antenna array according to an embodiment of the present invention;

[0032] Figure 11 : is the directional pattern at 5.8 GHz when port 101 of the broadband high isolation antenna array in an embodiment of the present invention is excited;

[0033] Figure 12 : is the directional pattern at 5.8 GHz when the port 201 of the broadband high isolation antenna array in the embodiment of the present invention is excited. DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0035] like Figures 1 to 8 As shown, a broadband high-isolation antenna array with the same circular polarization for transmission and reception is provided, which comprises, from bottom to top, a first dielectric plate, a perforated floor, a second dielectric plate, and a third dielectric plate. A first feeding network is provided on the back of the first dielectric plate, a second feeding network and a radiation patch are provided on the front of the second dielectric plate, and a parasitic patch is provided on the back of the third dielectric plate.

[0036] The radiation unit part is composed of eight radiation units, all of which work in linear polarization mode. The eight radiation units are arranged in a "well" shape according to the numbers from small to large, and are respectively recorded as the first radiation unit 1, the second radiation unit 2, the third radiation unit 3, the fourth radiation unit 4, the fifth radiation unit 5, the sixth radiation unit 6, the seventh radiation unit 7, and the eighth radiation unit 8; among them, the first radiation unit 1, the third radiation unit 3, the fifth radiation unit 5 and the seventh radiation unit 7 constitute the first radiation unit group; the second radiation unit 2, the fourth radiation unit 4, the sixth radiation unit 6 and the eighth radiation unit 8 constitute the second radiation unit group; the eight parasitic patches are located directly above the eight radiation units.

[0037] The feed network has two input ports and sixteen output ports, providing equal-amplitude, unequal-phase feeds to the first through eighth radiating elements. The first input port 101 corresponds to the first feed source 9, the fourth feed source 12, the fifth feed source 13, the eighth feed source 16, the ninth feed source 17, the twelfth feed source 20, the thirteenth feed source 21, and the sixteenth feed source 24. The second input port 201 corresponds to the second feed source 10, the third feed source 11, the sixth feed source 14, the seventh feed source 15, the tenth feed source 18, the eleventh feed source 19, the fourteenth feed source 22, and the fifteenth feed source 23.

[0038] The first radiating element 1 is excited by the first feed source 9 or the second feed source 10, the second radiating element 2 is excited by the third feed source 11 or the fourth feed source 12, the third radiating element 3 is excited by the fifth feed source 14 or the sixth feed source 14, the fourth radiating element 1 is excited by the seventh feed source 15 or the eighth feed source 16, the fifth radiating element 5 is excited by the ninth feed source 17 or the tenth feed source 18, the sixth radiating element 6 is excited by the eleventh feed source 19 or the twelfth feed source 20, the seventh radiating element 7 is excited by the thirteenth feed source 21 or the fourteenth feed source 22, and the eighth radiating element 8 is excited by the fifteenth feed source 23 or the sixteenth feed source 24;

[0039] The first feed source 9, the second feed source 10, the third feed source 11, the fourth feed source 12, the fifth feed source 13, the sixth feed source 14, the seventh feed source 15, the eighth feed source 16, the ninth feed source 17, the tenth feed source 18, the eleventh feed source 19, the twelfth feed source 20, the thirteenth feed source 21, the fourteenth feed source 22, the fifteenth feed source 23 and the sixteenth feed source 24 are excited with equal amplitudes, and the excitation phases of the first feed source 9, the fifth feed source 13, the ninth feed source 21 and the thirteenth feed source 21 are successively reduced by 90 o , wherein the excitation phase of the twelfth feed source 20 is the same as the excitation phase of the first feed source 9, and the excitation phases of the twelfth feed source 20, the sixteenth feed source 24, the fourth feed source 12, and the eighth feed source 16 are reduced by 90 o The excitation phases of the second feed source 10, the sixth feed source 14, the tenth feed source 18, and the fourteenth feed source 22 are reduced by 90 o , wherein the excitation phase of the third feed source 11 is the same as the excitation phase of the second feed source 10, and the excitation phases of the third feed source 11, the seventh feed source 15, the eleventh feed source 19, and the fifteenth feed source 23 are reduced by 90 o .

[0040] Correspondingly, when the input port 101 is excited, the first radiation element group and the second radiation element group are left-hand circular polarization; when the input port 201 is excited, the first radiation element group and the second radiation element group are left-hand circular polarization.

[0041] Here's a more specific example:

[0042] like Figures 1 to 8As shown, a broadband high-isolation antenna array for transmitting and receiving the same circular polarization includes a first feeding network, a first dielectric plate, an open-hole floor, a second dielectric plate, a second feeding network, a radiation patch array, an air layer, a parasitic patch array and a third dielectric plate stacked in sequence from bottom to top. The radiation patch array is composed of eight "well"-shaped radiation patches, and the eight parasitic patch units are at the same center as the eight radiation patch arrays. The first radiation unit 1, the third radiation unit 3, the fifth radiation unit 5 and the seventh radiation unit 7 constitute the first radiation unit group; the second radiation unit 2, the fourth radiation unit 4, the sixth radiation unit 6 and the eighth radiation unit 8 constitute the second radiation unit group; a sequential rotation sequence is used to generate circularly polarized waves. The first radiation unit 1 is placed as it is, and the third radiation unit 3 is rotated 90 degrees clockwise around the center of the array. o The fifth radiation unit 5 is rotated 180 degrees clockwise around the center of the array. o The seventh radiation element 7 is rotated 270 degrees clockwise around the center of the array. o The second radiation unit 2 is mirror-symmetrical to the first radiation unit 1 along the y-axis, and the fourth radiation unit 4 is rotated 90 degrees clockwise around the center of the array. o The sixth radiation element 6 is placed back and rotated 180 degrees clockwise around the center of the array. o The eighth radiation element 8 is rotated 270 degrees clockwise around the center of the array. o Then place it.

[0043] The feed network has two input ports 101 and 201 and sixteen output ports, providing equal-amplitude but unequal-phase feeds to the eight radiating elements 1, 2, 3, 4, 5, 6, 7, and 8. By inputting excitation from the two input ports 101 and 201 of the feed network, two different phase excitation distributions can be provided to the eight radiating elements, as follows:

[0044] When the excitation phase of the first feed source 9 is used as the reference phase (the phase difference with itself is 0), when the first radiation unit group 1, 3, 5, 7 is excited from the feed network input port 101, the excitation phases obtained are 0 o 、-90 o 、-180 o 、-270 o The excitation phases of the second radiation unit groups 2, 4, 6, and 8 are -180 o 、-270 o , 0 o 、-90 o , at this time the entire array antenna radiates left-hand circularly polarized waves; when excited from the feed network input port 201, the excitation phases obtained by the first radiation unit groups 1, 3, 5, and 7 are 0 o 、-90 o 、-180 o、-270 o , the excitation phases obtained by the second radiation unit groups 2, 4, 6, and 8 are 0 o 、-90 o 、-180 o 、-270 o , at this time the entire array antenna radiates left-hand circularly polarized waves.

[0045] The feed network is placed on the back of the first dielectric plate and the front of the second dielectric plate, connected by metal pillars. It includes excitation sources 101 and 201, a differential network 102, a second differential network, a first phase shifter 103, a second phase shifter 104, a third phase shifter 105, a fourth phase shifter 106, a fifth phase shifter 107, a sixth phase shifter 108, a seventh phase shifter 203, an eighth phase shifter 204, several microstrip lines, and a power divider. The connections are as follows:

[0046] First, the excitation source 101 located on the back of the first dielectric plate is subjected to equal amplitude and anti-phase power distribution through the differential network 102: the first path after distribution is then divided into two equal power paths, and then one of the paths is connected to the front of the second dielectric plate through the metal column 109, and then divided into two equal power paths. The first path formed is 90° through the first phase shifter 103. o Phase shift, connected to the sixteenth feed 24, the second path is connected to the first feed 9; the other path is 90 degrees through the second phase shifter 104 o Phase shifting, after phase shifting, is connected to the front of the second dielectric plate through the metal column 110, and then the power distribution is divided into two equal paths, and the third path formed is 90 degrees through the third phase shifter 105. o Phase shifting is performed, and the phase shifted signal is connected to the fourth feed source 12. The fourth path is connected to the fifth feed source 13. The other path distributed by the differential network 102 is first subjected to equal power distribution. Then, one of the paths is connected to the front of the second dielectric plate through the metal column 111, and then subjected to one-to-two equal power distribution. The fifth path formed is subjected to 90° phase shifting by the fourth phase shifter 106. o Phase shift, after phase shift, connected to the eighth feed 16, the sixth path is connected to the ninth feed 17; the other path is 90 degrees through the fifth phase shifter 107 o Phase shifting, after phase shifting, is connected to the front of the second dielectric plate through the metal column 112, and then the power distribution is divided into two equal paths, and the seventh path formed is 90 degrees through the sixth phase shifter 108. o Phase shift, after phase shift, connected to the thirteenth feed source 21, the eighth path is connected to the thirteenth feed source 21;

[0047] The excitation source 201 located on the back of the first dielectric plate performs equal-amplitude reverse power distribution through the second differential network: the first path after distribution is connected to the front of the second dielectric plate through the metal column 205, and then performs equal power distribution of one-to-two paths. One path performs equal power distribution of one-to-two paths and is connected to the fourteenth feed source 22 and the fifteenth feed source 23 respectively; the other path is 90° through the seventh phase shifter 203. o Phase shifting, and then one-to-two equal power distribution is performed, and they are connected to the second feed 10 and the third feed 11 respectively; the other path through the second differential network is first connected to the front of the second dielectric plate through the metal column 206, and then one-to-two equal power distribution is performed, one of which is one-to-two equal power distribution and is connected to the sixth feed 14 and the seventh feed 15 respectively; the other path is 90° through the eighth phase shifter 204. o Phase shifting is performed, and then equal power distribution is performed on one-to-two paths, which are connected to the tenth feed source 18 and the eleventh feed source 19 respectively.

[0048] Figure 9 : is the echo characteristic diagram of the broadband high isolation antenna array in the embodiment. Figure 6 The excitation port 101 in is port 1, set Figure 6 The excitation port 102 in is 2 ports. Figure 9 As shown in the figure, the return loss of port 1 (|S(1,1)|) and the return loss of port 2 (|S(2,2)|) are both greater than 14 dB from 5.3 GHz to 6.18 GHz, indicating that the antenna achieves broadband operating characteristics. The isolation between port 1 and port 2 (|S(1,2)|) is both greater than 40 dB from 5.3 GHz to 6.18 GHz, indicating that the antenna achieves broadband port isolation, and the antenna can transmit and receive without interfering with each other when operating simultaneously.

[0049] Figure 10 : is the axial ratio characteristic diagram of the broadband high isolation antenna array in the embodiment. Figure 10 As shown, when excited from the excitation port 101 and the excitation port 201, the axial ratio is less than 3, achieving broadband circular polarization characteristics.

[0050] Figure 11 : is the directional pattern of the broadband high isolation antenna array at 5.8 GHz when the port 101 is excited. Figure 11 As shown in the figure, when excited from the excitation port 101, the left-hand circular polarization gain (|GainLHCP|) in the normal direction (theta=0°) is ≥15 dB, and the right-hand circular polarization gain (|GainRHCP|) is ≤-20 dB. The antenna achieves good polarization isolation and good gain characteristics when excited from port 101.

[0051] Figure 12: is the directional pattern of the broadband high isolation antenna array at 5.8 GHz when the port 201 is excited. Figure 12 As shown in the figure, when excited from the excitation port 201, the left-hand circular polarization gain (|GainLHCP|) in the normal direction (theta=0°) is ≥15 dB, and the right-hand circular polarization gain (|GainRHCP|) is ≤-20 dB. The antenna achieves good polarization isolation and good gain characteristics when excited from port 201.

[0052] The above scheme is specifically designed with a center frequency of 5.8 GHz, using full-wave electromagnetic simulation and optimization in Ansys HFSS. The first and second dielectric plates have a relative permittivity of 2.65, a thickness of 0.8 mm, and a surface copper layer thickness of 0.035 mm. The third dielectric plate has a relative permittivity of 2.65, a thickness of 1 mm, a surface copper layer thickness of 0.035 mm, and an air layer thickness of 4 mm. The radiating patch is 15.8 mm long and 15.8 mm wide; the parasitic patch is 17.4 mm long and 17.4 mm wide. All microstrip lines not specifically described are 2.1 mm wide, corresponding to a 50 ohm characteristic impedance. The broadband phase shift network includes a one-to-two power divider, a 90° phase shifter, and a phase balancer. Input port 301 and output ports 302 and 303 are 2.1mm wide. Quarter-wavelength impedance transformation lines 304 and 305 are 8.99mm long and 1.2mm wide. The 90° phase shifter includes microstrip lines 306, 307, 308, 309, 310, and 311, each 0.596mm wide. Microstrip lines 306, 307, 310, and 311 are 7.54mm long, while microstrip lines 308 and 309 are 3mm long. The phase balancer includes a parallel ground line at both ends. Microstrip lines 312 and 314 are 4.46mm long and 0.56mm wide. The radius of the grounding metal post is 0.28mm. The metal posts 109, 110, 111, 112, 205, and 206 all have the same structure. 401 is a circular metal pad on the back of the first dielectric plate with a radius of 1.05mm, 402 is a metal cylinder with a radius of 0.5mm and a height of 1.635mm, 403 is a circular metal pad on the front of the second dielectric plate with a radius of 1.05mm, and 404 is a circular hole in the floor with a radius of 1.5mm. The differential networks 101 and 201 have the same structure, with the input end 501 and the output ends 502 and 503 all being microstrip lines with a width of 2.1 mm; the microstrip line 504 is 19.01 mm long and 1.8 mm wide; the microstrip lines 505 and 506 are 9.21 mm long and 1.16 mm wide; the microstrip line 507 is 18.43 mm long and 4.3 mm wide; the microstrip lines 508 and 509 are 9.21 mm long and 1.83 mm wide; the microstrip line 510 is 15.13 mm long and 1.83 mm wide, and 511 and 512 are 85 ohm resistors.

Claims

1. A broadband high-isolation antenna array with the same circular polarization for transmission and reception, characterized in that: It includes a first dielectric plate, a perforated floor, a second dielectric plate, and a third dielectric plate arranged from bottom to top. A first feeding network is provided on the back of the first dielectric plate, a second feeding network and a radiation patch are provided on the front of the second dielectric plate. The first feeding network and the second feeding network together constitute a feeding network structure. A parasitic patch is provided on the back of the third dielectric plate. The radiation patch is divided into eight radiation units, and the eight radiation units have the same structure. All radiation units operate in a linear polarization mode. The eight radiation units are distributed in a crisscross pattern from small to large according to the numbering, wherein the first, third, fifth and seventh radiation units constitute a first radiation unit group; the second, fourth, sixth and eighth radiation units constitute a second radiation unit group; the eight parasitic patches are respectively located directly above the eight radiation units; the first radiation unit group and the second radiation unit group are both left-hand circularly polarized; The feeding network structure has two input ports and sixteen output ports, providing equal-amplitude but unequal-phase feeding to eight radiating elements; the first input port of the first feeding network corresponds to the first, fourth, fifth, eighth, ninth, twelfth, thirteenth and sixteenth feed sources at the output ports; the second input port of the second feeding network corresponds to the second, third, sixth, seventh, tenth, eleventh, fourteenth and fifteenth feed sources at the output ports; The first radiating element is excited by the first or second feed source, the second radiating element is excited by the third or fourth feed source, the third radiating element is excited by the fifth or sixth feed source, the fourth radiating element is excited by the seventh or eighth feed source, the fifth radiating element is excited by the ninth or tenth feed source, the sixth radiating element is excited by the eleventh or twelfth feed source, the seventh radiating element is excited by the thirteenth or fourteenth feed source, and the eighth radiating element is excited by the fifteenth or sixteenth feed source.

2. The broadband high-isolation antenna array with the same circular polarization for transmission and reception according to claim 1, characterized in that: The first to sixteenth feeds are excited with equal amplitudes, and the excitation phases of the first, fifth, ninth, and thirteenth feeds are reduced by 90 degrees in sequence. o The excitation phase of the twelfth feed source is the same as that of the first feed source, and the excitation phases of the twelfth, sixteenth, fourth, and eighth feed sources decrease by 90 degrees respectively. o The excitation phase of the second, sixth, tenth and fourteenth feed sources decreases by 90 degrees respectively. o The excitation phase of the third feed source is the same as that of the second feed source, and the excitation phases of the third, seventh, eleventh, and fifteenth feed sources decrease by 90 degrees respectively. o .

3. The broadband high isolation antenna array with the same circular polarization for transmission and reception according to claim 1, characterized in that: The feeding network offsets the residual signal between ports through a differential network and a broadband phase shift network, and includes a first excitation source, a second excitation source, a first differential network, a second differential network, a first phase shifter, a second phase shifter, a third phase shifter, a fourth phase shifter, a fifth phase shifter, a sixth phase shifter, a seventh phase shifter, and an eighth phase shifter; The first excitation source located on the back side of the first dielectric plate performs equal-amplitude and anti-phase power distribution through the first differential network, and obtains a first path and a second path after distribution; The first path is split into two paths with equal power distribution to obtain the third and fourth paths; the third path is connected to the front of the second dielectric plate through a metal column, and then split into two paths with equal power distribution to obtain the fifth and sixth paths; The fifth path is 90 degrees through the first phase shifter o Phase shift, connected to the sixteenth feed, the sixth path connected to the first feed; The fourth path is 90 degrees through the second phase shifter o Phase shifting, after which the phase shifting is connected to the front of the second dielectric plate via a metal column, and then one-to-two equal power distribution is performed to obtain the seventh and eighth channels; The seventh path is 90 degrees through the third phase shifter o Phase shift, after phase shift, connected to the fourth feed source, and the eighth channel connected to the fifth feed source; The second route is divided into two routes with equal power distribution, resulting in the ninth and tenth routes; The ninth channel is connected to the front of the second dielectric plate through a metal column, and then divided into two equal power channels to obtain the eleventh and twelfth channels; The eleventh channel is 90° through the fourth phase shifter o Phase shift, after phase shift, connected to the eighth feed, and the twelfth channel connected to the ninth feed; The tenth path is 90° through the fifth phase shifter o Phase shifting, after which the phase shift is connected to the front of the second dielectric plate via a metal column, and then one-to-two equal power distribution is performed to obtain the 13th and 14th channels; The thirteenth path is 90° through the sixth phase shifter o Phase shift, after phase shifting, connected to the 13th feed, and the 14th channel connected to the 13th feed; The second excitation source located on the back side of the first dielectric plate performs equal-amplitude reverse power distribution through the second differential network to obtain the fifteenth path and the sixteenth path; The fifteenth channel is connected to the front of the second dielectric plate through a metal column, and then divided into two equal power channels to obtain the seventeenth and eighteenth channels; the seventeenth channel is divided into two equal power channels and connected to the fourteenth and fifteenth feed sources respectively; The eighteenth path is 90° through the seventh phase shifter o Phase shifting, and then performing one-to-two equal power distribution, which are connected to the second feed and the third feed respectively; The sixteenth path is connected to the front of the second dielectric plate through a metal column, and then divided into two paths with equal power distribution to obtain the nineteenth and twentieth paths; The nineteenth route is divided into two routes with equal power distribution, and is connected to the sixth feed and the seventh feed respectively; The twentieth path is 90° through the eighth phase shifter. o Phase shifting is performed, and then equal power distribution is performed into two paths, which are connected to the tenth feed and the eleventh feed respectively.

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