A horizontal omnidirectional filtering antenna

Abstract

This invention provides a horizontal omnidirectional filtering antenna, comprising an antenna housing, a metal inner core, a coaxial feed mechanism, a connecting bracket, and an open-circuit filter stub assembly. One end of the metal inner core is connected to the top inner surface of the antenna housing, and the other end of the metal inner core is fixedly connected to the coaxial feed mechanism, which is fixed to the bottom of the antenna housing. The antenna housing has a radiating slot that divides the antenna housing into a first housing at the top and a second housing at the bottom. The connecting bracket connects the first housing and the second housing. The first housing and the second housing each form two radiating slots to achieve horizontal omnidirectional radiation. The filtering effect is achieved by placing open-circuit stubs. This antenna has the advantages of easy production, high practicality, high frequency selectivity, and good out-of-band suppression performance, and can well meet the requirements of modern communication systems.

Description

Technical Field

[0001] This invention belongs to the technical field of wireless communication antennas, and particularly relates to a horizontal omnidirectional filtering antenna. Background Technology

[0002] With the continuous innovation of modern wireless communication, radar, and electronic systems, the electromagnetic environment in which terminals operate is becoming increasingly complex. Under various complex terrains and harsh weather conditions, higher demands are placed on antenna performance. Horizontal omnidirectional filtering antennas, capable of transmitting and receiving wireless signals in all directions on the horizontal plane, are particularly suitable for indoor and outdoor wireless communication and are widely used in civilian and commercial fields. To ensure high-quality communication, it is necessary not only to cover the service area but also to maximize antenna gain. Under the same conditions, increasing antenna gain can extend the distance electromagnetic energy can propagate. Therefore, researching a high-performance omnidirectional high-gain antenna is of great significance in the field of modern communication and information systems. Summary of the Invention

[0003] The purpose of this invention is to provide a rod-shaped high-gain horizontal omnidirectional filtering antenna with simple structure and outstanding performance.

[0004] The present invention is implemented as follows: a horizontal omnidirectional filtering antenna includes an antenna housing, a metal inner core, a coaxial feeding mechanism, a connecting bracket, and an open-circuit filtering stub group. One end of the metal inner core is connected to the top inner surface of the antenna housing, and the other end of the metal inner core is fixedly connected to the coaxial feeding mechanism, which is fixed to the bottom of the antenna housing.

[0005] The antenna housing has a radiating slot that divides it into a first housing at the top and a second housing at the bottom. One end of the connecting bracket is connected to the outer surface of the first housing, and the other end is connected to the outer surface of the second housing. The antenna housing is a cylindrical cavity structure with sealed top and bottom surfaces. The radiating slot is an annular slot coaxial with the cylindrical cavity. The open-circuit filter stub is fixed to the metal core and located inside the second housing.

[0006] Furthermore, the metal inner core includes an inner core rod and a slow-wave structure protruding from the inner core rod. Both the inner core rod and the slow-wave structure are housed within the antenna housing, and the slow-wave structure is integrally formed with the inner core rod.

[0007] Furthermore, the inner core rod is a cylindrical columnar structure, and the slow wave structure is a saucer shape that is thick in the middle and thin at the periphery.

[0008] Furthermore, a plurality of connecting brackets are connected between the first housing and the second housing, and the plurality of connecting brackets are uniformly and symmetrically arranged on the antenna housing with the metal inner core as the central axis.

[0009] Furthermore, the antenna housing has multiple radiating slots that divide the antenna housing into a first housing, a second housing, and several third housings. The first housing is connected to the adjacent third housing, several adjacent third housings are connected to each other, and the second housing is connected to the adjacent third housing through the connecting bracket.

[0010] Furthermore, the connecting bracket includes a first contact portion, a connecting rod portion, and a second contact portion. The first contact portion and the second contact portion are respectively disposed at both ends of the connecting rod portion, and the first contact portion and the second contact portion are respectively connected to the connecting rod portion at right angles in the same direction. The first contact portion is vertically fixed to the outer surface of the first housing, the second housing, or the third housing, and the second contact portion is vertically fixed to the outer surface of the third housing, the first housing, or the second housing.

[0011] Furthermore, the bottom of the second housing is provided with a through hole for fixing the coaxial power supply mechanism; the coaxial power supply mechanism includes an inner conductor, an outer conductor and an insulating medium, one end of the inner conductor passes through the through hole and is fixed to the end of the metal inner core, the insulating medium is sleeved on the other end of the inner conductor, the outer conductor is sleeved on the outside of the insulating medium, and the outer conductor is fixed to the outer surface of the bottom of the second housing.

[0012] Furthermore, the open-circuit filter stub group includes high-frequency filter stubs and low-frequency filter stubs. Multiple high-frequency filter stubs and multiple low-frequency filter stubs are fixed to the outer surface of the metal core. The multiple high-frequency filter stubs are arranged symmetrically about the metal core as the central axis, and the multiple low-frequency filter stubs are arranged symmetrically about the metal core as the central axis.

[0013] Furthermore, both the high-frequency filter stub and the low-frequency filter stub are right-angle bent structures. One end of the high-frequency filter stub and one end of the low-frequency filter stub are fixed to the outer surface of the metal inner core. The other ends of the high-frequency filter stub and the low-frequency filter stub point in the same direction toward the top of the first housing or toward the bottom of the second housing, respectively.

[0014] Furthermore, the radiation slit is located at the position where the current amplitude is the largest.

[0015] The beneficial effects of this invention are as follows:

[0016] This solution presents a horizontal omnidirectional filtering antenna with a metal core positioned at the center of the antenna housing, similar to a coaxial structure. Radiation slots separate the antenna housing into a first shell and a second shell, which are connected by a connecting bracket. The first and second shells each form two radiation slots to achieve omnidirectional horizontal radiation. The filtering effect is achieved by placing open-circuit stubs. This design offers advantages such as ease of production, high practicality, high frequency selectivity, and good out-of-band suppression, effectively meeting the requirements of modern communication systems. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the horizontal omnidirectional filtering antenna structure according to Embodiment 1 of the present invention;

[0018] Figure 2 This is a schematic diagram of the exploded structure of the horizontal omnidirectional filter antenna according to Embodiment 1 of the present invention;

[0019] Figure 3 This is a cross-sectional view of the horizontal omnidirectional filtering antenna according to Embodiment 1 of the present invention;

[0020] Figure 4 The return loss characteristics of the horizontal omnidirectional filtering antenna in Embodiment 1 of the present invention are shown in |S 11 |Graph;

[0021] Figure 5 This is the radiation pattern of the horizontal omnidirectional filter antenna in Embodiment 1 of the present invention at a center frequency of 2.65 GHz;

[0022] Figure 6 This is a three-dimensional radiation pattern of the horizontal omnidirectional filter antenna at a center frequency of 2.65 GHz, according to Embodiment 1 of the present invention.

[0023] Figure 7 This is a schematic diagram of the horizontal omnidirectional filtering antenna structure according to Embodiment 2 of the present invention;

[0024] Figure 8 This is a schematic diagram of the exploded structure of the horizontal omnidirectional filter antenna according to Embodiment 2 of the present invention;

[0025] Figure 9 This is a cross-sectional view of the horizontal omnidirectional filtering antenna according to Embodiment 2 of the present invention;

[0026] Figure 10 The return loss characteristics of the horizontal omnidirectional filtering antenna in Embodiment 2 of the present invention are shown in |S 11 |Graph;

[0027] Figure 11 This is the radiation pattern of the horizontal omnidirectional filter antenna in Embodiment 2 of the present invention at a center frequency of 2.9 GHz;

[0028] Figure 12This is a three-dimensional radiation pattern of the horizontal omnidirectional filter antenna at a center frequency of 2.9 GHz, according to Embodiment 2 of the present invention.

[0029] Figure 13 This is a schematic diagram of the horizontal omnidirectional filtering antenna structure according to Embodiment 3 of the present invention;

[0030] Figure 14 This is a cross-sectional view of the horizontal omnidirectional filtering antenna according to Embodiment 3 of the present invention;

[0031] Figure 15 The return loss characteristics of the horizontal omnidirectional filter antenna in Embodiment 3 of the present invention are shown in |S 11 |Graph;

[0032] Figure 16 This is the radiation pattern of the horizontal omnidirectional filter antenna in Embodiment 3 of the present invention at a center frequency of 2.8 GHz;

[0033] Figure 17 This is a three-dimensional radiation pattern of the horizontal omnidirectional filter antenna at a center frequency of 2.8 GHz, according to Embodiment 3 of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 100. Antenna housing; 110. First housing; 120. Second housing; 121. Through hole; 130. Third housing; 140. Radiation slot;

[0036] 200. Metal inner core; 210. Inner core rod; 220. Slow-wave structure; 221. First slow-wave structure; 222. Second slow-wave structure;

[0037] 300. Coaxial power supply mechanism; 310. Inner conductor; 320. Outer conductor; 330. Insulating medium;

[0038] 400. Connecting bracket; 410. First contact portion; 420. Connecting rod portion; 430. Second contact portion;

[0039] 500, Open-circuit filter stub group; 510, High-frequency filter stub; 520, Low-frequency filter stub; 530, Intermediate filter stub. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0041] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "front," "rear," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention; the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly, for example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or they can refer to the internal communication of two components. For those skilled in the art, the specific meaning of the terms in this invention can be understood according to the specific circumstances.

[0042] Typically, in engineering applications, the return loss characteristic |S11| of an antenna is required to be less than -10dB, which is a normal standard. The filter in this invention can work normally in the passband under the condition of meeting the requirements, and has high selectivity, good out-of-band suppression performance, and at the same time, the in-band radiation pattern is consistent and achieves horizontal omnidirectional radiation.

[0043] Example 1

[0044] See Figure 1-6 This embodiment discloses a horizontal omnidirectional filtering antenna, including an antenna housing 100, a metal core 200, a coaxial feed mechanism 300, four connecting brackets 400, and an open-circuit filter stub group 500. The antenna housing 100 has a radiation slot 140, which divides the antenna housing 100 into a first housing 110 at the top of the antenna housing 100 and a second housing 120 at the bottom of the antenna housing 100. One end of the metal core 200 is connected to the top inner surface of the first housing 110, and the other end of the metal core 200 is fixedly connected to the coaxial feed mechanism 300, which is fixed to the bottom of the second housing 120. One end of the connecting bracket 400 is connected to the outer surface of the first housing 110, and the other end of the connecting bracket 400 is connected to the outer surface of the second housing 120. The open-circuit filter stub group 500 is fixed to the metal core 200 and is located inside the second housing 120. The antenna housing 100 is a cylindrical cavity structure with sealed top and bottom surfaces, and the radiation slot 140 is a circular annular slot coaxial with the cylindrical cavity. The radiation slot 140 is located at the position of maximum current amplitude to achieve the best radiation effect.

[0045] In this embodiment, the metal core 200 is composed of a cylindrical inner core rod 210. The metal core 200 is coaxial with the centers of the first housing 110 and the second housing 120. The lengths of the metal core 200 and the antenna housing 100 are approximately one wavelength at the center frequency.

[0046] In this embodiment, four connecting brackets 400 are evenly and symmetrically arranged on the antenna housing 100 with the metal inner core 200 as the central axis. It is understood that the metal brackets are used to connect the two separate housing parts for ease of manufacturing. The number of brackets is not limited to four, as long as they are symmetrically placed and can support two adjacent housings.

[0047] In this embodiment, the connecting bracket 400 includes a first contact portion 410, a connecting rod portion 420, and a second contact portion 430. The first contact portion 410 and the second contact portion 430 are respectively disposed at both ends of the connecting rod portion 420, and the first contact portion 410 and the second contact portion 430 are respectively connected to the connecting rod portion 420 at right angles in the same direction. The first contact portion 410 is vertically fixed to the outer surface of the first housing 110, the second housing 120, or the third housing 130, and the second contact portion 430 is vertically fixed to the outer surface of the third housing 130, the first housing 110, or the second housing 120.

[0048] In this embodiment, the bottom of the second housing 120 is provided with a through hole 121 for fixing the coaxial feed mechanism 300. The coaxial feed mechanism 300 includes an inner conductor 310, an outer conductor 320, and an insulating medium 330. One end of the inner conductor 310 passes through the through hole 121 and is fixed to the end of the metal inner core 200. The insulating medium 330 is sleeved on the other end of the inner conductor 310, and the outer conductor 320 is sleeved on the outside of the insulating medium 330 and fixed to the outer surface of the bottom of the second housing 120. It can be understood that the coaxial feed mechanism 300 is used to connect to an external circuit. The insulating medium 330 insulates and isolates the inner conductor 310 and the outer conductor 320, so that the inner conductor 310 is electrically connected to the metal core and the outer conductor 320 is electrically connected to the antenna housing 100, forming a complete circuit.

[0049] In this embodiment, the open-circuit filter stub group includes two high-frequency filter stubs 510 and two low-frequency filter stubs 520. The lengths of the two high-frequency filter stubs 510 are longer than the lengths of the two low-frequency filter stubs 520. The two high-frequency filter stubs 510 are placed at 180° to each other and orthogonal to the two low-frequency filter stubs 520, thereby ensuring the symmetry of the structure. The total length of the high-frequency filter stubs 510 is approximately one-quarter wavelength of the high-frequency zero point, and the total length of the low-frequency filter stubs 520 is approximately one-quarter wavelength of the low-frequency zero point.

[0050] It should be noted that both the high-frequency filter stub 510 and the low-frequency filter stub 520 are right-angle bent structures. One end of the high-frequency filter stub 510 and one end of the low-frequency filter stub 520 are fixed to the outer surface of the metal inner core 200. The other ends of the high-frequency filter stub 510 and the low-frequency filter stub 520 point in the same direction to the top of the first housing 110 or to the bottom of the second housing 120, respectively. Because the internal space of the structure is limited, the distance between the antenna outer shell 100 and the metal inner core 200 is less than the stub length required to generate a null point, so a bent structure is adopted.

[0051] like Figure 4 As shown in the S-parameter response and gain curves of the above structure, it can be seen that the passband center frequency of the filter antenna is 2.65 GHz, S11 is less than -10 dB, the lower stopband has two zeros and the out-of-band rejection is -19 dB, the upper stopband has one zero and the out-of-band rejection is -9 dB, which enables the filter antenna to achieve good in-band performance and out-of-band rejection performance.

[0052] like Figure 5-6 As shown, the above structure exhibits a horizontal omnidirectional radiation pattern at a center frequency of 2.65 GHz, with a main polarization gain of 2 dB and a cross-polarization of less than -45 dB.

[0053] Example 2

[0054] See Figure 7-12Unlike Embodiment 1, this embodiment discloses a horizontal omnidirectional filtering antenna, including an antenna housing 100, a metal inner core 200, a coaxial feeding mechanism 300, two sets of four connecting brackets 400, and an open-circuit filtering stub group 500. The antenna housing 100 has two radiation slots 140, which divide the antenna housing 100 into a first housing 110 at the top of the antenna housing 100, a second housing 120 at the bottom of the antenna housing 100, and a third housing 130 between the first housing 110 and the second housing 120. One end of the metal inner core 200 is connected to the first housing 110. The top inner surface is connected to the metal inner core 200, and the other end of the metal inner core 200 is fixedly connected to the coaxial feed mechanism 300, which is fixed to the bottom of the second housing 120. One end of the first group of four connecting brackets 400 is connected to the outer surface of the first housing 110, and the other end of the first group of four connecting brackets 400 is connected to the outer surface of the third housing 130. One end of the second group of four connecting brackets 400 is connected to the outer surface of the third housing 130, and the other end of the second group of four connecting brackets 400 is connected to the outer surface of the second housing 120. The open-circuit filter stub group 500 is fixed to the metal inner core 200 and is located inside the second housing 120. The antenna housing 100 is a cylindrical cavity structure with sealed top and bottom surfaces, and the radiation slot 140 is an annular slot coaxial with the cylindrical cavity. The radiation slot 140 is opened at the position with the largest current amplitude to achieve the best radiation effect.

[0055] In this embodiment, the metal inner core 200 includes an inner core rod 210 and a slow wave structure 220 protruding from the inner core rod 210. Both the inner core rod 210 and the slow wave structure 220 are housed within the antenna housing 100, and the slow wave structure and the inner core rod 210 are integrally formed.

[0056] Furthermore, the inner core rod 210 is a cylindrical columnar structure, and the slow-wave structure 220 includes a first slow-wave structure 221 and a second slow-wave structure 222. One first slow-wave structure 221 is located inside the first housing 110 and one inside the second housing 120, while four second slow-wave structures 222 are located inside the third housing 130. Both the first slow-wave structure 221 and the second slow-wave structure 222 are saucer-shaped, thicker in the middle and thinner at the periphery, and the outer diameter of the first slow-wave structure 221 is smaller than the outer diameter of the second slow-wave structure 222. The arrangement of the slow-wave structure 220 can increase the length through which current flows, thereby reducing the overall length of the antenna housing 100 and the metal inner core 200, making the antenna structure more concise. It is understandable that the outer diameters of the first slow-wave structure 221 and the second slow-wave structure 222 are the optimal solutions obtained through calculation and testing based on different requirements.

[0057] In this embodiment, the open-circuit filter stub group includes two high-frequency filter stubs 510, two intermediate filter stubs 530, and two low-frequency filter stubs 520. The lengths of the two high-frequency filter stubs 510, the two intermediate filter stubs 530, and the two low-frequency filter stubs 520 decrease sequentially. The two high-frequency filter stubs 510, the two intermediate filter stubs 530, and the two low-frequency filter stubs 520 are uniformly and symmetrically distributed at 180° on the metal core 200.

[0058] like Figure 10 As shown in the S-parameter response and gain curves of the above structure, it can be seen that the passband center frequency of the filter antenna is 2.9 GHz, S11 is less than -10dB, the lower stopband has two zeros and the out-of-band rejection is -25dB, the upper stopband has one zero and the out-of-band rejection is -40dB, which enables the filter antenna to achieve good in-band performance and out-of-band rejection performance.

[0059] like Figure 11-12 As shown, the above structure exhibits a horizontal omnidirectional radiation pattern at a center frequency of 2.9 GHz, with a main polarization gain of 4.9 dB and a cross-polarization of less than -45 dB.

[0060] Example 3

[0061] See Figure 13-17Unlike Embodiment 1, this embodiment discloses a horizontal omnidirectional filtering antenna, including an antenna housing 100, a metal core 200, a coaxial feeding mechanism 300, four sets of four connecting brackets 400, and an open-circuit filtering stub group 500. The antenna housing 100 has four radiation slots 140, which divide the antenna housing 100 into a first housing 110 at the top of the antenna housing 100, a second housing 120 at the bottom of the antenna housing 100, and three third housings 130 between the first housing 110 and the second housing 120. One end of the metal core 200 is connected to the top inner surface of the first housing 110, and the other end of the metal core 200... The antenna is fixedly connected to the coaxial feed mechanism 300, which is fixed to the bottom of the second housing 120. One end of the first group of four connecting brackets 400 is connected to the outer surface of the first housing 110, and the other end is connected to the outer surface of the third housing 130. The two ends of the second and third groups of four connecting brackets 400 are respectively connected to the outer surface of the adjacent third housing 130. One end of the fourth group of four connecting brackets 400 is connected to the outer surface of the third housing 130, and the other end is connected to the outer surface of the second housing 120. The open-circuit filter stub group 500 is fixed to the metal inner core 200 and is located inside the second housing 120. The antenna housing 100 is a cylindrical cavity structure with sealed top and bottom surfaces. The radiation slot 140 is an annular slot coaxial with the cylindrical cavity. The radiation slot 140 is opened at the position with the largest current amplitude to achieve the best radiation effect.

[0062] In this embodiment, the metal inner core 200 includes an inner core rod 210 and a slow wave structure 220 protruding from the inner core rod 210. Both the inner core rod 210 and the slow wave structure 220 are housed within the antenna housing 100, and the slow wave structure and the inner core rod 210 are integrally formed.

[0063] Furthermore, the inner core rod 210 is a cylindrical columnar structure, and the slow-wave structure 220 includes a first slow-wave structure 221 and a second slow-wave structure 222. One first slow-wave structure 221 is located inside the first housing 110 and one inside the second housing 120, and three second slow-wave structures 222 are located inside each third housing 130. Both the first slow-wave structure 221 and the second slow-wave structure 222 are saucer-shaped, thicker in the middle and thinner at the periphery, and the outer diameter of the first slow-wave structure 221 is smaller than the outer diameter of the second slow-wave structure 222. The arrangement of the slow-wave structure 220 can increase the length through which current flows, thereby reducing the overall length of the antenna housing 100 and the metal inner core 200, making the antenna structure more concise. It is understandable that the outer diameters of the first slow-wave structure 221 and the second slow-wave structure 222 are the optimal solutions obtained through calculation and testing based on different requirements.

[0064] like Figure 15As shown in the S-parameter response and gain curves of the above structure, it can be seen that the passband center frequency of the filter antenna is 2.8 GHz, S11 is less than -10 dB, the lower stopband has two zeros and the out-of-band rejection is -21 dB, the upper stopband has one zero and the out-of-band rejection is -31 dB, which enables the filter antenna to achieve good in-band performance and out-of-band rejection performance.

[0065] like Figure 16-17 As shown, the above structure exhibits a horizontal omnidirectional radiation pattern at a center frequency of 2.9 GHz, with a main polarization gain of 6.25 dB and a cross-polarization of less than -45 dB.

[0066] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A horizontally omnidirectional filtered antenna, characterized by, The antenna includes an antenna housing, a metal inner core, a coaxial feed mechanism, a connecting bracket, and an open-circuit filter stub assembly. One end of the metal inner core is connected to the top inner surface of the antenna housing, and the other end of the metal inner core is fixedly connected to the coaxial feed mechanism, which is fixed to the bottom of the antenna housing. The antenna housing has a radiating slit that divides the antenna housing into a first housing at the top of the antenna housing and a second housing at the bottom of the antenna housing. One end of the connecting bracket is connected to the outer surface of the first housing, and the other end of the connecting bracket is connected to the outer surface of the second housing.

2. The horizontal omni-directional filter antenna according to claim 1, characterized in that, The metal inner core includes an inner core rod and a slow-wave structure protruding from the inner core rod. Both the inner core rod and the slow-wave structure are housed within the antenna housing, and the slow-wave structure is integrally formed with the inner core rod.

3. The horizontal omnidirectional filtering antenna according to claim 2, characterized in that, The inner core rod is a cylindrical columnar structure, and the slow wave structure is a saucer shape that is thick in the middle and thin at the periphery.

4. The horizontal omnidirectional filtering antenna according to claim 1, characterized in that, A plurality of connecting brackets are connected between the first housing and the second housing, and the plurality of connecting brackets are evenly and symmetrically arranged on the antenna housing with the metal inner core as the central axis.

5. The horizontal omnidirectional filtering antenna according to claim 1, characterized in that, The antenna housing has multiple radiating slots that divide it into a first housing, a second housing, and several third housings. The first housing is connected to the adjacent third housing, the several adjacent third housings are connected to each other, and the second housing is connected to the adjacent third housing through the connecting bracket.

6. The horizontal omnidirectional filtering antenna according to claim 5, characterized in that, The connecting bracket includes a first contact portion, a connecting rod portion, and a second contact portion. The first contact portion and the second contact portion are respectively disposed at both ends of the connecting rod portion, and the first contact portion and the second contact portion are respectively connected to the connecting rod portion at right angles in the same direction. The first contact portion is vertically fixed to the outer surface of the first housing, the second housing, or the third housing, and the second contact portion is vertically fixed to the outer surface of the third housing, the first housing, or the second housing.

7. The horizontal omnidirectional filtering antenna according to claim 1, characterized in that, The bottom of the second housing is provided with a through hole for fixing the coaxial power supply mechanism; the coaxial power supply mechanism includes an inner conductor, an outer conductor and an insulating medium, one end of the inner conductor passes through the through hole and is fixed to the end of the metal inner core, the insulating medium is sleeved on the other end of the inner conductor, the outer conductor is sleeved on the outside of the insulating medium and the outer conductor is fixed to the outer surface of the bottom of the second housing.

8. The horizontal omnidirectional filtering antenna according to claim 1, characterized in that, The open-circuit filter stub group includes high-frequency filter stubs and low-frequency filter stubs. Multiple high-frequency filter stubs and multiple low-frequency filter stubs are fixed to the outer surface of the metal core. The multiple high-frequency filter stubs are arranged symmetrically about the metal core as the central axis, and the multiple low-frequency filter stubs are arranged symmetrically about the metal core as the central axis.

9. The horizontal omnidirectional filtering antenna according to claim 8, characterized in that, Both the high-frequency filter stub and the low-frequency filter stub are right-angle bent structures. One end of the high-frequency filter stub and one end of the low-frequency filter stub are fixed to the outer surface of the metal inner core. The other ends of the high-frequency filter stub and the low-frequency filter stub point in the same direction to the top of the first housing or to the bottom of the second housing, respectively.

10. The horizontal omnidirectional filtering antenna according to claim 1, characterized in that, The radiation slit is located at the position where the current amplitude is the largest.

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