阅读说明：本技术 一种基于e面***波导的双工喇叭天线 (Duplex horn antenna based on E-plane split waveguide ) 是由 傅继承 谢泽明 于 2019-09-27 设计创作，主要内容包括：本发明公开了一种基于E面分裂波导的双工喇叭天线,包括E面喇叭、E面分裂波导、上金属波导腔、下金属波导腔；E面分裂波导一端与E面喇叭小口径一端相连,另一端与上金属波导腔和下金属波导腔连接,上金属波导腔的另一端通过信号输入端口与限流器相连,下金属波导腔的另一端通过波导拐弯头与第二信号输入端口相连。本发明提出的双工喇叭天线具有以下优点,能够同时接受和发射信号,端口隔离度高,高选择性,增益平坦；结构简单可靠；易于集成；适用于VSAT卫星通信天线；可用作抛物面天线的馈源,并能起到抛物面天线的自支撑作用。(The invention discloses a duplex horn antenna based on an E-plane splitting waveguide, which comprises an E-plane horn, an E-plane splitting waveguide, an upper metal waveguide cavity and a lower metal waveguide cavity, wherein the E-plane horn is connected with the upper metal waveguide cavity; one end of the E-surface splitting waveguide is connected with the small-caliber end of the E-surface horn, the other end of the E-surface splitting waveguide is connected with the upper metal waveguide cavity and the lower metal waveguide cavity, the other end of the upper metal waveguide cavity is connected with the current limiter through the signal input port, and the other end of the lower metal waveguide cavity is connected with the second signal input port through the waveguide elbow. The duplex horn antenna provided by the invention has the advantages that the duplex horn antenna can receive and transmit signals at the same time, the port isolation degree is high, the selectivity is high, and the gain is flat; the structure is simple and reliable; the integration is easy; the antenna is suitable for a VSAT satellite communication antenna; the feed can be used as a feed source of the parabolic antenna and can play a self-supporting role of the parabolic antenna.)

1. a duplex horn antenna based on E-plane splitting waveguide, characterized in that the duplex filtering horn antenna comprises: the waveguide cavity comprises an E-plane horn (1), an E-plane split waveguide (2), an upper metal waveguide cavity (3) and a lower metal waveguide cavity (4); one end of the E-face split waveguide (2) is connected with the small-caliber end of the E-face horn (1), the other end of the E-face split waveguide is connected with the upper metal waveguide cavity (3) and the lower metal waveguide cavity (4), the other end of the upper metal waveguide cavity (3) is connected with the current limiter (14) through the signal input port (16), and the other end of the lower metal waveguide cavity (4) is connected with the second signal input port (17) through the waveguide elbow (15).

2. The duplex horn antenna based on the E-plane splitting waveguide as claimed in claim 1, wherein there is a space between the upper metallic waveguide cavity (3) and the lower metallic waveguide cavity (4).

3. The duplex horn antenna based on the E-plane splitting waveguide according to the claim 1, wherein the upper metal waveguide cavity (3) is divided into an upper channel first resonant cavity (18), an upper channel second resonant cavity (19) and an upper channel third resonant cavity (20) by a first pair of inductive diaphragms (5), a second pair of inductive diaphragms (6), a third pair of inductive diaphragms (7) and a fourth pair of inductive diaphragms (8) in sequence; the capacitive diaphragm (13), the current limiter (14) and the signal input port (16) form a fourth resonant cavity (21);

The lower metal waveguide cavity (4) is sequentially divided into a lower channel first resonant cavity (22), a lower channel second resonant cavity (23) and a lower channel third resonant cavity (24) by a fifth pair of inductive diaphragms (9), a sixth pair of inductive diaphragms (10), a seventh pair of inductive diaphragms (11) and an eighth pair of inductive diaphragms (13).

4. The duplex horn antenna based on the E-plane splitting waveguide as claimed in claim 1, wherein the upper metallic waveguide cavity (3) and the lower metallic waveguide cavity ((4) are both rectangular waveguide cavities.

5. The duplex horn antenna based on the E-plane splitting waveguide as claimed in claim 3, wherein the first pair of inductive irises (5), the second pair of inductive irises (6), the third pair of inductive irises (7) and the fourth pair of inductive irises (8) are respectively used as four impedance inversion transformers to form a third-order Chebyshev filter.

6. the duplex horn antenna based on the E-plane splitting waveguide as claimed in claim 3, wherein the fifth pair of inductive diaphragms (9), the sixth pair of inductive diaphragms (10), the seventh pair of inductive diaphragms (11) and the eighth pair of inductive diaphragms (12) are respectively used as four impedance inversion transformers to form a third-order Chebyshev filter.

7. The duplex horn antenna based on the E-plane splitting waveguide according to claim 3, wherein the upper channel is a fourth resonant cavity (21) formed by the first resonant cavity (18), the second resonant cavity (19), the third resonant cavity (20), the capacitive diaphragm (13), the current limiter (14) and the signal input port (16), and the operating principal modes of the first resonant cavity (18), the second resonant cavity (19), the third resonant cavity (20) and the fourth resonant cavity (21) are TE101 modes.

8. The duplex horn antenna based on the E-plane splitting waveguide as claimed in claim 1, wherein the three main operating modes of the lower channel first resonant cavity (22), the lower channel second resonant cavity (23) and the lower channel third resonant cavity (24) are TE101 mode.

9. The duplex horn antenna based on the E-plane splitting waveguide as claimed in claim 1, wherein the current limiter 14 is a cavity recess structure, which is equivalent to an inductor, and is used for increasing a transmission zero point to improve the isolation of the port; a capacitive diaphragm (13) is also introduced to counteract the effect of the current limiter (14).

10. the duplex horn antenna based on the E-plane splitting waveguide as claimed in claim 1, wherein the first signal input port (16) and the second signal input port (17) are rotated 90 degrees for installation and testing, wherein the first signal input port is connected with the current limiter (14) and the second signal input port (17) is connected with the waveguide bend (15).

Technical Field

The invention relates to the technical field of wireless communication, in particular to a duplex horn antenna based on an E-plane split waveguide.

Background

The antenna and the microwave filter are indispensable key components in a wireless communication system, a satellite communication system, a modern microwave relay communication system and the like. The antenna itself is reversible, i.e., the same pair of antennas is used for both transmitting and receiving electromagnetic signals. The main function of the microwave filter is to select the desired signal to filter out unwanted signals, passing the desired signal in this frequency band at a low loss in a certain useful frequency range, while attenuating the frequency components in other frequency ranges to very low levels. Therefore, the performance advantage of the microwave filter of the antenna, which is an important part of the wireless communication system, largely determines the quality of the system, and the size of the microwave filter directly affects the size and portability of the whole system.

With the rapid development of modern wireless communication demands, the demands of users for high-performance portable terminal devices are becoming more and more extensive, and miniaturization and integration are becoming new development trends. The duplex antenna is designed by combining the antenna and the microwave filter, so that the structure of a radio frequency front-end system can be more compact, unnecessary loss can be reduced, and the miniaturization and integration of a modern wireless communication system can be realized more easily. In a typical communication system, antennas and filters are often designed separately as two independent subsystems, but due to mutual influence between devices and mismatching between ports, the overall performance of the cascaded system is easily deteriorated, and the loss of the system is increased. In order to eliminate the influence, a matching network needs to be additionally added between the two, which easily makes the system more complicated. The size is also larger, which is not favorable for realizing miniaturization. Therefore, the antenna and the filter are directly integrated, so that an additional matching network which needs to be added can be omitted, the size and the weight of the system can be reduced, the loss can be reduced, and the whole performance of the system can be improved.

The duplex filtering antenna can simultaneously realize the functions of transmitting and receiving, filtering, transmitting-receiving separation and anti-interference of wireless electromagnetic waves by using one component, can realize high efficiency, low cost and light weight of integrated wireless equipment, and can be widely applied to systems such as a wireless communication system, a satellite communication system, modern microwave relay communication and the like. The existing microstrip duplex antenna generally has the disadvantages of low port isolation, large antenna transmitting and receiving frequency interval, narrow bandwidth and low antenna gain, so further research is needed.

Disclosure of Invention

The invention aims to solve the defects in the prior art that a waveguide horn antenna is difficult to have both filtering characteristics and duplex characteristics, and provides a duplex horn antenna based on an E-plane splitting waveguide, which has the advantages of simple structure, easiness in tuning, good frequency selectivity, flat gain and the like.

the invention is realized by at least one of the following technical schemes.

A duplex horn antenna based on an E-plane splitting waveguide, said duplex filtering horn antenna comprising: the waveguide cavity comprises an E-plane horn, an E-plane split waveguide, an upper metal waveguide cavity and a lower metal waveguide cavity; one end of the E-surface splitting waveguide is connected with the small-caliber end of the E-surface horn, the other end of the E-surface splitting waveguide is connected with the upper metal waveguide cavity and the lower metal waveguide cavity, the other end of the upper metal waveguide cavity is connected with the current limiter through the signal input port, and the other end of the lower metal waveguide cavity is connected with the second signal input port through the waveguide elbow.

Further, a space exists between the upper metal waveguide cavity and the lower metal waveguide cavity.

Furthermore, the E surface (wide side) of the E-surface horn is opened, and the H surface (narrow side) is unchanged, so that the radiation gain and the directionality of the filter antenna are improved, and the effect of reducing side lobes is achieved.

Furthermore, the upper metal waveguide cavity is sequentially divided into an upper channel first resonant cavity, an upper channel second resonant cavity and an upper channel third resonant cavity by a first pair of inductive diaphragms, a second pair of inductive diaphragms, a third pair of inductive diaphragms and a fourth pair of inductive diaphragms; the capacitive diaphragm, the current limiter and the signal input port form a fourth resonant cavity;

The lower metal waveguide cavity is sequentially divided into a lower channel first resonant cavity, a lower channel second resonant cavity and a lower channel third resonant cavity by a fifth pair of inductive diaphragms, a sixth pair of inductive diaphragms, a seventh pair of inductive diaphragms and an eighth pair of inductive diaphragms.

Furthermore, the upper metal waveguide cavity and the lower metal waveguide cavity are both rectangular waveguide cavities.

Furthermore, the first pair of inductive diaphragms, the second pair of inductive diaphragms, the third pair of inductive diaphragms and the fourth pair of inductive diaphragms are respectively used as four impedance inversion converters to form a third-order Chebyshev filter.

Furthermore, the fifth pair of inductive diaphragms, the sixth pair of inductive diaphragms, the seventh pair of inductive diaphragms and the eighth pair of inductive diaphragms are respectively used as four impedance inversion converters to form a third-order Chebyshev filter.

Furthermore, the first resonant cavity, the second resonant cavity, the third resonant cavity, the capacitive diaphragm, the current limiter and the signal input port of the upper channel form a fourth resonant cavity, and the operating main modes of the first resonant cavity, the second resonant cavity, the third resonant cavity and the fourth resonant cavity are all TE101 modes.

Further, the three resonant cavity working main modes of the first resonant cavity of the lower channel, the second resonant cavity of the lower channel and the third resonant cavity of the lower channel are TE101 modes.

Furthermore, the current limiter is of a cavity concave structure, is equivalent to an inductor, is used for increasing a transmission zero point, and plays a role in improving the isolation degree of the port; a capacitive diaphragm is also introduced to counteract the effect of the current limiter.

Further, the first signal input port and the second signal input port are rotated by 90 degrees for installation and testing, wherein the first signal input port is connected to the current limiter and the second signal input port is connected to the waveguide corner.

the invention relates to a high-power transmission device, which comprises an E-surface loudspeaker, an E-surface split waveguide, a transmitting channel inductive diaphragm type 3-order Chebyshev filter and a receiving channel inductive diaphragm type 3-order Chebyshev filter which are loaded on the upper side and the lower side of the E-surface split waveguide, a transmitting channel current limiter, a receiving channel waveguide elbow, a transmitting port and a receiving port. The antenna has both filtering characteristic and radiation characteristic, wherein the filtering characteristic has duplex characteristic and is generated by upper and lower channel filters of the split waveguide, and the radiation characteristic is generated by an E-plane horn. By adjusting the width of the window of the inductance diaphragm and the distance between the adjacent inductance diaphragms, the coupling strength between the adjacent resonant cavities, the external quality factor of the filter and the radiation quality factor of the antenna can be controlled. The isolation degree of the two ports is improved by introducing the current limiter; by introducing the E-plane horn, the radiation gain and the directivity of the antenna can be improved, and the side lobe is reduced. The duplex horn antenna provided by the invention has the advantages that the duplex horn antenna can receive and transmit signals at the same time, the port isolation degree is high, the selectivity is high, and the gain is flat; the structure is simple and reliable; the integration is easy; the antenna is suitable for a VSAT satellite communication antenna; the feed can be used as a feed source of the parabolic antenna and can play a self-supporting role of the parabolic antenna.

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

1. The duplex horn antenna based on the E-plane split waveguide has the advantages that the duplex horn antenna simultaneously has a filtering characteristic, a duplex characteristic and a radiation characteristic, wherein the filtering characteristic is generated by two filters formed by an upper channel and a lower channel, the duplex characteristic is generated by the E-plane split waveguide and the filters formed by the two channels, and the radiation characteristic is generated by an E-plane horn.

2. The coupling strength between adjacent resonant cavities, the external quality factor of the filter and the radiation quality factor of the antenna can be controlled by adjusting the width of the inductive diaphragm window, the filtering characteristic can be controlled by adjusting the distance between the adjacent inductive diaphragm windows, and the filter can be used as the fourth order of the filter by adjusting the height and the length of a current limiter in the upper channel filter, the height of a capacitive diaphragm and the distance between the capacitive diaphragm and an input port, and simultaneously the isolation degree of the two ports is improved.

3. When the E-plane horn, the E-plane split waveguide, the upper channel filter, the lower channel filter and the signal input port are well connected and matched, the E-plane split waveguide duplex horn antenna can be formed, meanwhile, the E-plane split waveguide duplex horn antenna has filtering characteristics, duplex characteristics and radiation characteristics, radiation gain and directionality of the antenna can be improved, and side lobes are reduced.

4. The duplex filtering antenna provided by the invention has the following advantages: the insertion loss is small; the filter has good passband standing wave characteristics and high out-of-band attenuation; the gain is flat; high selectivity; low side lobes; low cross polarization; the structure is simple and reliable; the integration is easy; the processing is easy; the method is suitable for various communication systems.

Drawings

Fig. 1 is a three-dimensional structure diagram of an E-plane splitting waveguide-based duplex horn antenna according to the present embodiment;

Fig. 2 is a front view of an E-plane splitting waveguide duplex horn antenna according to the present embodiment;

fig. 3 is a top view of the duplex horn antenna based on the E-plane splitting waveguide according to the embodiment;

Fig. 4 is a perspective structural diagram of an upper channel signal input port of the duplex horn antenna based on the E-plane splitting waveguide according to the embodiment;

Fig. 5 is a perspective structural view of a lower channel signal input port of the duplex horn antenna based on the E-plane splitting waveguide according to the embodiment;

Fig. 6 is a graph of simulated S-parameters of the duplex horn antenna based on the E-plane splitting waveguide according to the embodiment;

FIG. 7 is a graph showing the variation of simulated gain with frequency of the antenna of this embodiment;

FIG. 8 is a yoz plane simulation directional diagram excited at the frequency of 11.5GHz of the transmitting port of the present embodiment;

FIG. 9 is an xoz plane simulation directional diagram excited by the frequency of the transmitting port of the present embodiment being 11.5 GHz;

FIG. 10 is a yoz plane simulation directional diagram excited at the frequency of 14.5GHz of the transmitting port of the present embodiment;

FIG. 11 is an xoz plane simulation pattern excited at the transmitting port frequency of 14.5GHz according to the embodiment;

Wherein: 1-E surface horn, 2-E surface splitting waveguide, 3-upper layer metal waveguide cavity, 4-lower layer metal waveguide cavity, 5-first pair of inductive diaphragms, 6-second pair of inductive diaphragms, 7-third pair of inductive diaphragms, 8-fourth pair of inductive diaphragms, 9-fifth pair of inductive diaphragms, 10-sixth pair of inductive diaphragms, 11-seventh pair of inductive diaphragms, 12-eighth pair of inductive diaphragms, 13-capacitive diaphragms, 14-current limiter, 15-waveguide elbow-, 16-first signal input port, 17-second signal input port, 18-upper channel first resonant cavity, 19-upper channel second resonant cavity, 20-upper channel third resonant cavity, 21-fourth resonant cavity, 22-lower channel first resonant cavity, 23-lower channel second resonant cavity, 24-lower channel third resonant cavity.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention.

as shown in fig. 1, an E-plane splitting waveguide-based duplex horn antenna of the present embodiment includes: the waveguide cavity comprises an E-plane horn 1, an E-plane split waveguide 2, an upper metal waveguide cavity 3 and a lower metal waveguide cavity 4; one end of the E-surface split waveguide 2 is connected with the small-caliber end of the E-surface horn 1, and the other end of the E-surface split waveguide is connected with the upper metal waveguide cavity 3 and the lower metal waveguide cavity 4 and used for separately receiving and sending signals. The other end of the upper metallic waveguide cavity 3 is connected with a current limiter 14 through a signal input port 16, and the other end of the lower metallic waveguide cavity 4 is connected with a second signal input port 17 through a waveguide elbow 15.

The upper metal waveguide cavity 3 is sequentially divided into an upper channel first resonant cavity 18, an upper channel second resonant cavity 19 and an upper channel third resonant cavity 20 by a first pair of inductive diaphragms 5, a second pair of inductive diaphragms 6, a third pair of inductive diaphragms 7 and a fourth pair of inductive diaphragms 8, and meanwhile, the capacitive diaphragm 13, the current limiter 14 and the signal input port 16 form a fourth resonant cavity 21;

The lower metal waveguide cavity 4 is sequentially divided into a lower channel first resonant cavity 22, a lower channel second resonant cavity 23 and a lower channel third resonant cavity 24 by a fifth pair of inductive diaphragms 9, a sixth pair of inductive diaphragms 10, a seventh pair of inductive diaphragms 11 and an eighth pair of inductive diaphragms 13.

As shown in fig. 2 and 3, the E-plane split waveguide duplex horn antenna structure is symmetrical. FIG. 2 is a drawing1, wherein: the thickness of all diaphragms is 1mm, the width A of the large-caliber end of the E-face horn 1 is 19.05mm, the height H of the horn is 25mm, the distance dH between the upper channel and the lower channel of the upper metal waveguide cavity 3 and the lower metal waveguide cavity 4 is 1mm, the length of the channel is LL (LH) 70.3mm, and the distance between the diaphragms between the upper channel and the lower channel is L respectively₁₀＝8mm，L₁₁＝14.42mm，L₁₂＝15.5mm，L₁₃The distance between each diaphragm between the lower channels is L respectively as 13mm₂₀＝9.38mm，L₂₁＝9.3mm，L₂₂＝11.766mm，L₂₃10.76mm, the height of the channel is W₁4.65mm, the height a of the capacitive diaphragm 13 is 3.65mm, and the distance X from the signal input port 16₃10mm, width W of signal input port 16₂9.525mm, restrictor 14 length b 3.5mm, height c 1mm, signal input port 17 width W₂9.525mm, the inclination angle alpha of the waveguide elbow 15 is 45 DEG, and X is₁＝0.5*W₁，X₂＝0.5*W₂。

fig. 3 is a top view of fig. 1, where the waveguide width is equal to the width of the large-caliber end of the horn, and a is 19.05mm, and the distances between the first pair of inductive diaphragms 5, the second pair of inductive diaphragms 6, the third pair of inductive diaphragms 7, and the fourth pair of inductive diaphragms 8 in the upper metal waveguide cavity 3 are S₁₁＝13.3mm，S₁₂＝8.7mm，S₁₃＝8.4mm，S₁₄12.9 mm; the distances among the fifth pair of inductive diaphragms 9, the sixth pair of inductive diaphragms 10, the seventh pair of inductive diaphragms 11 and the eighth pair of inductive diaphragms 13 in the lower metal waveguide cavity 4 are respectively S₂₁＝10.66mm，S₂₂＝6.1mm，S₂₃＝6.1mm，S₂₄＝9mm。

The E surface of the E surface loudspeaker 1 is opened, the H surface is unchanged, the E surface loudspeaker is used for the radiation gain and the directionality of the one draft filter antenna, and the effect of reducing the side lobe is achieved.

The upper metal waveguide cavity 3 and the lower metal waveguide cavity 4 are both rectangular waveguides.

the first pair of inductive diaphragms 5, the second pair of inductive diaphragms 6, the third pair of inductive diaphragms 7 and the fourth pair of inductive diaphragms 8 are respectively used as four impedance inversion converters to form a third-order Chebyshev filter.

the fifth pair of inductive diaphragms 9, the sixth pair of inductive diaphragms 10, the seventh pair of inductive diaphragms 11 and the eighth pair of inductive diaphragms 12 are respectively used as four impedance inversion transformers to form a third-order Chebyshev filter.

The operating main modes of the first resonant cavity 18, the second resonant cavity 19, the third resonant cavity 20 and the fourth resonant cavity 21 of the upper channel are TE101 modes.

The operating main modes of the first resonant cavity 22, the second resonant cavity 23 and the third resonant cavity 24 of the lower channel are TE101 modes.

As shown in fig. 4 and 5, the current limiter 14 is a cavity recess structure, is a current limiter for improving the isolation of the port, and can be equivalent to an inductor, so as to add a transmission zero point and play a role in improving the isolation of the port; a capacitive diaphragm 13 is also introduced to counteract the effect of the current limiter 14. In the figure, the width of the channel is 19.05mm, and the height W is₁4.65mm, the height a of the capacitive diaphragm 13 is 3.65mm, and the distance X from the signal input port 16₃10mm, width W of signal input port 16₂9.525mm, the restrictor 14 has a length b of 3.5mm and a height c of 1 mm.

The first signal input port 16, which is connected to the flow restrictor 14, and the second signal input port 17, which is connected to the waveguide bend 15, are rotated 90 degrees for installation and testing.

Fig. 5 is a lower port signal input port, and specific reference numbers and sizes are shown in the figure. In the figure, the width of the channel is 19.05mm, and the height W is₁4.65mm, the signal input port 17 has a width W₂9.525mm, the inclination angle alpha of the waveguide elbow 15 is 45 DEG, and X is₁＝0.5*W₁，X₂＝0.5*W₂。

When the center frequency f is required_{Hair-like device}＝11.5GHz，f_{Harvesting machine}At 14.5GHz, the signal input port and the signal output port use a standard rectangular waveguide BJ120, and all the diaphragms have a thickness Δ S of 1 mm. And simulating and optimizing the structure by using three-dimensional simulation software HFSS.

When transmitting, a signal is sent from a transmitting port, namely, the first signal input port 16, and is transmitted to the E-face loudspeaker 1 through the upper metal waveguide cavity 3, the capacitive diaphragm 13, the fourth pair of inductive diaphragms 8, the third pair of inductive diaphragms 7, the second pair of inductive diaphragms 6, and the first pair of inductive diaphragms 5 of the upper metal waveguide cavity 3, and is radiated out by the E-face loudspeaker 1.

When receiving, a received signal is received from the E-plane horn 1, and the E-plane horn 1 passes through the fifth pair of inductive diaphragms 9, the sixth pair of inductive diaphragms 10, the seventh pair of inductive diaphragms 11, and the eighth pair of inductive diaphragms 12 in the cavity of the lower-layer metal waveguide cavity 4, and finally passes through the waveguide elbow 15, and is output from a receiving port, that is, the second signal input port 17.

The signal input port 16 of the antenna operates in a frequency band with a center frequency of 11.5 GHz; the receive port 17 operates in a frequency band having a center frequency of 14.5 GHz.

Fig. 6 shows a simulated S-curve plot for an embodiment duplex filtered antenna. The horizontal axis represents the frequency of the input signal and ranges from 10GHz to 16GHz, the vertical axis represents the logarithmic magnitude dB of the S parameter, the reflection loss of the transmitting port 1612.6dB of the antenna ranges from 10.91GHz to 12.24GHz, the relative bandwidth is 11.5%, and the reflection loss of the receiving port 1712.4dB ranges from 13.98GHz to 15GHz, and the relative bandwidth is 7%. The isolation of the two ports is greater than 47dB in both frequency bands.

Fig. 7 shows the results of a gain simulation of the duplex filtered antenna of the embodiment. The horizontal axis represents the frequency of the input signal, ranging from 10GHz to 16GHz, the vertical axis represents the gain (dB), the low-frequency channel gain is about 8.4dB, and the high-frequency channel gain is about 9.4dB within the antenna operating frequency range. It can be seen from the figure that the antenna has the advantages of flat gain, high selectivity, high out-of-band rejection, etc.

Fig. 8 and fig. 9 are simulation results of an E-plane directional diagram (yoz plane) and an H-plane directional diagram (xoz plane) at the center frequency of 11.5GHz of the filtering antenna of the embodiment, respectively, and it can be seen from the graphs that both the E-plane cross polarization is less than-35 dB, and both the H-plane cross polarization is less than-40 dB.

Fig. 10 and fig. 11 are simulation results of an E-plane directional diagram (yoz plane) and an H-plane directional diagram (xoz plane) at a center frequency of 14.5GHz of the filtering antenna of the embodiment, respectively, and it can be seen from the graphs that both the E-plane cross polarization is less than-30 dB, and both the H-plane cross polarization is less than-40 dB.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents and are included in the scope of the present invention.