A broadband reflectionless differential filtering circularly polarized patch antenna

Abstract

The application discloses a broadband reflection-free differential filtering circularly polarized patch antenna, which comprises a circular defective radiation patch, a circular coupling patch, a feeding probe, a feeding network, a dielectric plate, a metal defective ground plate and a short-circuit needle; the circular defective radiation patch comprises two first circular defective coupling structures and two second circular defective coupling structures which are of the same structure; the first circular defective coupling structure is located on the right side of the circular defective radiation patch, and the second circular defective coupling structure is located on the upper side of the circular defective radiation patch. The patch antenna can not only effectively suppress common-mode noise and improve the electromagnetic compatibility of a communication system, but also simultaneously realize circularly polarized radiation, frequency selective filtering and broadband differential mode and common mode reflection-free absorption characteristics in a single device, thereby improving the overall performance of a differential communication system.

Description

Technical Field

[0001] This invention relates to a circularly polarized patch antenna, specifically a broadband, reflection-free, differentially filtered, circularly polarized patch antenna. Background Technology

[0002] As mobile communication systems increasingly demand higher data transmission rates and reliability, traditional unbalanced single-ended RF circuits are highly sensitive to external noise and prone to common-mode interference, leading to increased bit error rate and decreased receiver sensitivity. In contrast, balanced differential circuits, due to their inherent common-mode noise suppression capabilities, demonstrate significant advantages in improving the signal integrity of the RF front-end. Balanced differential filters, as key components of differential communication systems, effectively filter out out-of-band interference in differential signals. However, their traditional reflective design reflects stopband signal energy back to the preceding circuitry, causing nonlinear interference and degrading the system's signal-to-noise ratio. To address this issue, reflectionless filters dissipate stopband energy by introducing an absorption network, achieving full-band input port matching and significantly improving the overall system stability.

[0003] In recent years, filter antennas that combine filtering functionality with antenna radiation characteristics have become a research hotspot, aiming to reduce cascade losses and overall size in the RF front-end. However, most existing filter antennas are still based on single-ended designs and cannot be directly applied to differential communication systems; simply adding a balun for conversion introduces additional insertion loss. Furthermore, most existing differential filter antennas with reflection-free characteristics rely on complementary duplexer architectures. The inconsistent absorption branch structure in this architecture easily leads to impedance mismatch and problems such as deterioration of differential-mode transmission response at the passband edge, making it difficult to achieve broadband reflection-free absorption characteristics for both differential and common modes while maintaining good radiation performance. Therefore, it is indeed necessary to propose a broadband reflection-free differential filter circularly polarized patch antenna to provide an effective and reliable antenna solution for modern differential communication systems. Summary of the Invention

[0004] To address the aforementioned technical problem that differentially filtered circularly polarized patch antennas struggle to achieve broadband differential-mode and common-mode non-reflection absorption characteristics while maintaining good radiation performance, a broadband non-reflection differentially filtered circularly polarized patch antenna is provided. The specific technical solution includes: a circular defect radiating patch, a circular coupling patch, a feed probe, a feed network, a dielectric substrate, a metal defect ground plane, and a short-circuit pin.

[0005] The circular defect radiation patch includes two identical first circular defect coupling structures and a second circular defect coupling structure; wherein the first circular defect coupling structure is located on the right side of the circular defect radiation patch, and the second circular defect coupling structure is located on the upper side of the circular defect radiation patch. The circular coupling patch includes two identical first circular coupling patches and a second circular coupling patch; wherein the center of the first circular coupling patch coincides with the center of the first circular defect coupling structure, and the center of the second circular coupling patch coincides with the center of the second circular defect coupling structure. The power supply probe includes two identical first power supply probes and a second power supply probe; wherein one end of the first power supply probe is connected to the center of the first circular coupling patch and the other end is connected to the power supply network; one end of the second power supply probe is connected to the center of the second circular coupling patch and the other end is connected to the power supply network. The metal defect floor includes two identical first-fed circular defect structures and a second-fed circular defect structure; wherein the center of the first-fed circular defect structure is coaxial with the center of the first circular defect coupling structure, and the center of the second-fed circular defect structure is coaxial with the center of the second circular defect coupling structure. The dielectric substrate includes an upper dielectric substrate and a lower dielectric substrate; the circular defect radiation patch and the circular coupling patch are located on the upper surface of the upper dielectric substrate; the metal defect ground plane is located on the upper surface of the lower dielectric substrate; the power supply network is located on the lower surface of the lower dielectric substrate; the power supply probe passes through the upper dielectric substrate, the metal defect ground plane and the lower dielectric substrate in sequence to connect the circular coupling patch and the power supply network. The shorting pins include shorting pin I, shorting pin II, shorting pin III, shorting pin IV, and shorting pin V; The power supply network includes a differential input port A+ and a differential input port A. Differential inverting line, common-mode in-band absorption resistor, three-quarter wavelength transmission line, quarter wavelength transmission line, first microstrip connection line, second microstrip connection line, first differential mode out-of-band absorption resistor, second differential mode out-of-band absorption resistor, phase delay line, first bandpass filter structure and second bandpass filter structure; One end of the differential inverting line is connected to the differential input port A+, and the other end is connected to the differential input port A. Connected; One end of the common-mode band absorption resistor is connected to the midpoint of the differential antiphase line, and the other end is connected to the metal defect ground plane through short-circuit pin I; One end of the three-quarter wavelength transmission line is connected to the differential input port A+, and the other end is connected to the first microstrip connection line; one end of the quarter wavelength transmission line is connected to the differential input port A+. One end is connected to the first microstrip line, and the other end is connected to the second microstrip connection line. One end of the first microstrip connection line is connected to a three-quarter wavelength transmission line, and the other end is connected to a first bandpass filter structure; one end of the second microstrip connection line is connected to a quarter wavelength transmission line, and the other end is connected to a phase delay line. One end of the first differential mode external absorption resistor is connected to the connection between the three-quarter wavelength transmission line and the first microstrip connection line, and the other end is connected to the connection between the quarter wavelength transmission line and the second microstrip connection line; one end of the second differential mode external absorption resistor is connected to the connection between the first microstrip connection line and the first bandpass filter structure, and the other end is connected to the connection between the second microstrip connection line and the phase delay line; One end of the phase delay line is connected to the second microstrip connection line, and the other end is connected to the second bandpass filter structure; The first bandpass filter structure is identical to the second bandpass filter structure; the first bandpass filter structure includes a low-impedance filter resonator, a bent coupling line, and a high-impedance matching resonator. One end of the low-impedance filter resonator is connected to the connection between the first microstrip connecting line and the bent coupling line, and the other end is connected to the metal defect ground plane through shorting pin II; one end of the bent coupling line is connected to the first microstrip connecting line, and the other end is connected to the first feed probe; one end of the high-impedance matching resonator is connected to the connection between the bent coupling line and the first feed probe, and the other end is connected to the metal defect ground plane through shorting pin III.

[0006] Furthermore, a gap capacitor is provided between the circular defect radiation patch and the circular coupling patch.

[0007] Furthermore, an air layer is provided between the upper dielectric plate and the lower dielectric plate.

[0008] Furthermore, the thickness of the air layer is 8 mm.

[0009] Furthermore, the electric fields of the first circular coupling patch and the second circular coupling patch have a 90-degree phase difference.

[0010] Furthermore, the 90-degree phase difference is introduced by the phase delay line.

[0011] Furthermore, the non-reflective absorption characteristics within the common-mode band can be adjusted by regulating the absorption resistance within the common-mode band.

[0012] The differential mode out-of-band non-reflection absorption characteristics are adjusted by adjusting the first differential mode out-of-band absorption resistor and the second differential mode out-of-band absorption resistor.

[0013] The impedance matching characteristics between the first feed probe and the feed network are adjusted by modifying the high impedance matching resonator.

[0014] To extend the functionality of differential filtering antennas by eliminating reflections, this invention provides a broadband, reflection-free differential filtering circularly polarized patch antenna. This patch antenna effectively suppresses common-mode noise and improves the electromagnetic compatibility of communication systems. Furthermore, this patch antenna can simultaneously achieve circularly polarized radiation, frequency-selective filtering, and broadband differential-mode and common-mode reflection-free absorption characteristics in a single device, thereby enhancing the overall performance of differential communication systems. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is an exploded view of the structure of a broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to the present invention. Figure 2 This is a side view of a broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to the present invention. Figure 3 This is a diagram of the radiating patch structure of a broadband non-reflective differential filter circularly polarized patch antenna according to the present invention. Figure 4 This is a diagram of the metal ground plane structure of a broadband non-reflective differential filter circularly polarized patch antenna according to the present invention. Figure 5 This is a diagram of the feed network structure of a broadband non-reflection differential filter circularly polarized patch antenna according to the present invention. Figure 6 This is a graph showing the gain and hybrid S-parameters of a broadband, reflection-free, differentially filtered, circularly polarized patch antenna as a function of frequency, as described in this invention. Figure 7 This is a curve showing the axial ratio as a function of frequency for a broadband, reflection-free, differentially filtered, circularly polarized patch antenna as described in this invention. Figure 8 is a normalized directivity pattern at the center frequency of a broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to the present invention. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0018] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0019] A broadband, reflection-free, differentially filtered, circularly polarized patch antenna includes: a circular defective radiating patch 1, a circular coupling patch 2, a feed probe 3, a feed network 4, a dielectric substrate 5, a metallic defective ground plane 6, and a short-circuit pin 7. The circular defect radiation patch 1 includes two identical structures: a first circular defect coupling structure 11 and a second circular defect coupling structure 12; wherein the first circular defect coupling structure 11 is located on the right side of the circular defect radiation patch 1, and the second circular defect coupling structure 12 is located on the upper side of the circular defect radiation patch 1. The circular coupling patch 2 includes two identical first circular coupling patches 21 and second circular coupling patches 22; wherein the center of the first circular coupling patch 21 coincides with the center of the first circular defect coupling structure 11, and the center of the second circular coupling patch 22 coincides with the center of the second circular defect coupling structure 12. The power supply probe 3 includes two identical first power supply probes 31 and second power supply probes 32; wherein one end of the first power supply probe 31 is connected to the center of the first circular coupling patch 21 and the other end is connected to the power supply network 4; one end of the second power supply probe 32 is connected to the center of the second circular coupling patch 22 and the other end is connected to the power supply network 4. The metal defect floor 6 includes two identical first-feed circular defect structures 61 and second-feed circular defect structures 62; wherein the center of the first-feed circular defect structure 61 is coaxial with the center of the first circular defect coupling structure 11, and the center of the second-feed circular defect structure 62 is coaxial with the center of the second circular defect coupling structure 12. The dielectric substrate 5 includes an upper dielectric substrate 51 and a lower dielectric substrate 52; the circular defect radiation patch 1 and the circular coupling patch 2 are located on the upper surface of the upper dielectric substrate 51; the metal defect ground plane 6 is located on the upper surface of the lower dielectric substrate 52; the power supply network 4 is located on the lower surface of the lower dielectric substrate 52; the power supply probe 3 passes through the upper dielectric substrate 51, the metal defect ground plane 6 and the lower dielectric substrate 52 in sequence to connect the circular coupling patch 2 and the power supply network 4. The shorting pin 7 includes shorting pin I 71, shorting pin II 72, shorting pin III 73, shorting pin IV 74 and shorting pin V 75; The power supply network 4 includes differential input port A+ 41 and differential input port A 42. Differential inverting line; 43. Common-mode in-band absorption resistor; 44. Three-quarter wavelength transmission line; 45. Quarter wavelength transmission line; 46. First microstrip connection line; 47. Second microstrip connection line; 48. First differential-mode out-of-band absorption resistor; 49. Second differential-mode out-of-band absorption resistor; 410. Phase delay line; 411. First bandpass filter structure; 412. Second bandpass filter structure; 413. One end of the differential inverting line 43 is connected to the differential input port A+ 41, and the other end is connected to the differential input port A. 42 phases connected; One end of the common-mode band absorption resistor 44 is connected to the midpoint of the differential antiphase line 43, and the other end is connected to the metal defect ground plate 6 through the short-circuit pin I71. One end of the three-quarter wavelength transmission line 45 is connected to the differential input port A+ 41, and the other end is connected to the first microstrip connection line 47; one end of the quarter wavelength transmission line 46 is connected to the differential input port A+ 41. 42 is connected to the first phase, and the other end is connected to the second microstrip connection line 48. One end of the first microstrip connection line 47 is connected to the three-quarter wavelength transmission line 45, and the other end is connected to the first bandpass filter structure 412; one end of the second microstrip connection line 48 is connected to the quarter wavelength transmission line 46, and the other end is connected to the phase delay line 411; One end of the first differential mode external absorption resistor 49 is connected to the connection between the three-quarter wavelength transmission line 45 and the first microstrip connection line 47, and the other end is connected to the connection between the quarter wavelength transmission line 46 and the second microstrip connection line 48; one end of the second differential mode external absorption resistor 410 is connected to the connection between the first microstrip connection line 47 and the first bandpass filter structure 412, and the other end is connected to the connection between the second microstrip connection line 48 and the phase delay line 411; One end of the phase delay line 411 is connected to the second microstrip connection line 48, and the other end is connected to the second bandpass filter structure 413; The first bandpass filter structure 412 has the same structure as the second bandpass filter structure 413; the first bandpass filter structure 412 includes a low-impedance filter resonator 4121, a bent coupling line 4122 and a high-impedance matching resonator 4123. One end of the low-impedance filter resonator 4121 is connected to the connection between the first microstrip connection line 47 and the bent coupling line 4122, and the other end is connected to the metal defect ground plane 6 through the shorting pin II 72; one end of the bent coupling line 4122 is connected to the first microstrip connection line 47, and the other end is connected to the first feed probe 31; one end of the high-impedance matching resonator 4123 is connected to the connection between the bent coupling line 4122 and the first feed probe 31, and the other end is connected to the metal defect ground plane 6 through the shorting pin III 73.

[0020] Furthermore, a gap capacitor is provided between the circular defect radiation patch 1 and the circular coupling patch 2.

[0021] Furthermore, an air layer is provided between the upper dielectric plate 51 and the lower dielectric plate 52.

[0022] Furthermore, the thickness of the air layer is 8 mm.

[0023] Furthermore, the electric fields of the first circular coupling patch 21 and the second circular coupling patch 22 have a 90-degree phase difference.

[0024] Furthermore, the 90-degree phase difference is introduced by the phase delay line 411.

[0025] Furthermore, the non-reflective absorption characteristics within the common-mode band are adjusted by adjusting the absorption resistance 44 within the common-mode band.

[0026] Furthermore, by adjusting the first differential mode out-of-band absorption resistor 49 and the second differential mode out-of-band absorption resistor 410, the differential mode out-of-band non-reflection absorption characteristics are adjusted.

[0027] Furthermore, by adjusting the high-impedance matching resonator 4123, the impedance matching characteristics between the first feed probe 31 and the feed network 4 are adjusted.

[0028] Specific example: This example illustrates a broadband, reflection-free differentially filtered, circularly polarized patch antenna. Figure 6 This is a graph showing the gain and hybrid S-parameters of a broadband, reflection-free, differentially filtered, circularly polarized patch antenna as a function of frequency, according to the present invention. From... Figure 6 As can be seen, the broadband reflection-free differentially filtered circularly polarized patch antenna described in this invention has a center frequency of 2.0 GHz, a gain of 6.83 dBic at the center frequency of 2.0 GHz, a 3dB filtering relative bandwidth of 28%, and a differential mode reflection coefficient of | S ddAA | Less than in the frequency range of 0.87~3.07 GHz 10 dB, common-mode reflection coefficient | S ccAA | Smaller than 1.36~2.60 GHz in the frequency range 10 dB. This indicates that the broadband reflection-free differential filtered circularly polarized patch antenna described in this invention has good differential-mode and common-mode reflection-free absorption characteristics as well as frequency-selective filtering characteristics. Figure 7 This is a graph showing the axial ratio as a function of frequency for a broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to the present invention. From... Figure 7 As can be seen, the axial ratio of the broadband reflection-free differential filter circularly polarized patch antenna described in this invention is less than 3dB in the frequency range of 1.58~2.47GHz. Figure 8 shows the normalized directivity pattern of the broadband reflection-free differential filter circularly polarized patch antenna described in this invention at the center frequency. As can be seen from Figure 8, in the 120-degree spatial domain of the upper half-space, the right-hand circular polarization is much greater than the left-hand circular polarization, indicating that the broadband reflection-free differential filter circularly polarized patch antenna described in this invention has excellent circular polarization radiation characteristics.

[0029] In summary, the broadband non-reflective differential filter circularly polarized patch antenna described in this invention can not only effectively suppress common-mode noise and improve the electromagnetic compatibility characteristics of communication systems, but also simultaneously achieve circularly polarized radiation, frequency-selective filtering, and broadband differential and common-mode non-reflective absorption characteristics in a single device. Therefore, it is very suitable for application in various differential radio systems to improve the overall performance of the system.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A broadband, reflection-free, differentially filtered, circularly polarized patch antenna, characterized in that, include: Circular defect radiation patch (1), circular coupling patch (2), feed probe (3), feed network (4), dielectric substrate (5), metal defect ground plane (6) and shorting pin (7). The circular defect radiation patch (1) includes two identical structures: a first circular defect coupling structure (11) and a second circular defect coupling structure (12); wherein the first circular defect coupling structure (11) is located on the right side of the circular defect radiation patch (1), and the second circular defect coupling structure (12) is located on the upper side of the circular defect radiation patch (1). The circular coupling patch (2) includes two identical structures: a first circular coupling patch (21) and a second circular coupling patch (22); wherein the center of the first circular coupling patch (21) coincides with the center of the first circular defect coupling structure (11), and the center of the second circular coupling patch (22) coincides with the center of the second circular defect coupling structure (12); The power supply probe (3) includes two identical first power supply probes (31) and second power supply probes (32); wherein one end of the first power supply probe (31) is connected to the center of the first circular coupling patch (21) and the other end is connected to the power supply network (4); one end of the second power supply probe (32) is connected to the center of the second circular coupling patch (22) and the other end is connected to the power supply network (4); The metal defect floor (6) includes two identical structures: a first fed circular defect structure (61) and a second fed circular defect structure (62); wherein the center of the first fed circular defect structure (61) is coaxial with the center of the first circular defect coupling structure (11), and the center of the second fed circular defect structure (62) is coaxial with the center of the second circular defect coupling structure (12). The dielectric substrate (5) includes an upper dielectric substrate (51) and a lower dielectric substrate (52); the circular defect radiation patch (1) and the circular coupling patch (2) are located on the upper surface of the upper dielectric substrate (51); the metal defect ground plane (6) is located on the upper surface of the lower dielectric substrate (52); the power supply network (4) is located on the lower surface of the lower dielectric substrate (52); the power supply probe (3) passes through the upper dielectric substrate (51), the metal defect ground plane (6) and the lower dielectric substrate (52) in sequence to connect the circular coupling patch (2) and the power supply network (4); The shorting pin (7) includes shorting pin I (71), shorting pin II (72), shorting pin III (73), shorting pin IV (74) and shorting pin V (75). The power supply network (4) includes differential input port A+ (41) and differential input port A. (42) Differential inverting line (43) Common-mode in-band absorption resistor (44) Three-quarter wavelength transmission line (45) Quarter wavelength transmission line (46) First microstrip connection line (47) Second microstrip connection line (48) First differential mode out-of-band absorption resistor (49) Second differential mode out-of-band absorption resistor (410) Phase delay line (411) First bandpass filter structure (412) and Second bandpass filter structure (413); One end of the differential inverting line (43) is connected to the differential input port A+ (41), and the other end is connected to the differential input port A. (42) Connected; One end of the common-mode band absorption resistor (44) is connected to the midpoint of the differential antiphase line (43), and the other end is connected to the metal defect ground plane (6) through the short-circuit pin I (71). One end of the three-quarter wavelength transmission line (45) is connected to the differential input port A+ (41), and the other end is connected to the first microstrip connection line (47); one end of the quarter wavelength transmission line (46) is connected to the differential input port A+ (41). (42) Connected to the first end, and the other end connected to the second microstrip connection line (48); One end of the first microstrip connection line (47) is connected to the three-quarter wavelength transmission line (45), and the other end is connected to the first bandpass filter structure (412); one end of the second microstrip connection line (48) is connected to the quarter wavelength transmission line (46), and the other end is connected to the phase delay line (411); One end of the first differential mode external absorption resistor (49) is connected to the connection between the three-quarter wavelength transmission line (45) and the first microstrip connection line (47), and the other end is connected to the connection between the quarter wavelength transmission line (46) and the second microstrip connection line (48); one end of the second differential mode external absorption resistor (410) is connected to the connection between the first microstrip connection line (47) and the first bandpass filter structure (412), and the other end is connected to the connection between the second microstrip connection line (48) and the phase delay line (411); One end of the phase delay line (411) is connected to the second microstrip connection line (48), and the other end is connected to the second bandpass filter structure (413); The first bandpass filter structure (412) has the same structure as the second bandpass filter structure (413); the first bandpass filter structure (412) includes a low-impedance filter resonator (4121), a bent coupling line (4122), and a high-impedance matching resonator (4123). One end of the low-impedance filter resonator (4121) is connected to the connection between the first microstrip connection line (47) and the bent coupling line (4122), and the other end is connected to the metal defect ground plane (6) through the short-circuit pin II (72); one end of the bent coupling line (4122) is connected to the first microstrip connection line (47), and the other end is connected to the first feed probe (31); one end of the high-impedance matching resonator (4123) is connected to the connection between the bent coupling line (4122) and the first feed probe (31), and the other end is connected to the metal defect ground plane (6) through the short-circuit pin III (73).

2. The broadband reflection-free differential filter circularly polarized patch antenna according to claim 1, characterized in that: A gap capacitor is provided between the circular defect radiation patch (1) and the circular coupling patch (2).

3. The broadband reflection-free differential filter circularly polarized patch antenna according to claim 1, characterized in that: An air layer is provided between the upper dielectric plate (51) and the lower dielectric plate (52).

4. A broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to claim 3, characterized in that: The thickness of the air layer is 8 mm.

5. A broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to claim 1, characterized in that: There is a 90-degree phase difference between the electric fields of the first circular coupling patch (21) and the second circular coupling patch (22).

6. A broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to claim 5, characterized in that: The 90-degree phase difference is introduced by the phase delay line (411).

7. A broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to claim 1, characterized in that: The non-reflective absorption characteristics in the common-mode band are adjusted by adjusting the absorption resistance (44) in the common-mode band.

8. A broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to claim 1, characterized in that: The differential mode out-of-band non-reflective absorption characteristics are adjusted by adjusting the first differential mode out-of-band absorption resistor (49) and the second differential mode out-of-band absorption resistor (410).

9. A broadband, reflection-free, differentially filtered, circularly polarized patch antenna according to claim 1, characterized in that: The impedance matching characteristics between the first feed probe (31) and the feed network (4) are adjusted by adjusting the high impedance matching resonator (4123).

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