A bidirectional circularly polarized dual-frequency antenna and communication terminal

Abstract

The present application discloses a bidirectional circularly polarized dual-frequency antenna and a communication terminal, which relate to the field of satellite communication terminals. The bidirectional circularly polarized dual-frequency antenna comprises: an antenna cavity, a feed plate, a first radiation plate, a second radiation plate and a feed port; wherein: the feed plate, the first radiation plate and the second radiation plate are installed in the antenna cavity in a stacked form from the inside to the outside; the feed port is connected to the feed plate, for receiving external input feed and inputting it into the feed plate; the feed plate is used to receive feed and feed the first radiation plate and the second radiation plate; the first radiation plate and the second radiation plate form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the combined resonance of the feed. Through the embodiments of the present application, the bidirectional circularly polarized dual-frequency antenna can be made small in size, thin in thickness, easy to fold, easy to carry, and high in performance, which can meet the needs of various market scenarios.

Description

Technical Field

[0001] The present application relates to the field of satellite communication terminals, and in particular to a bidirectional circularly polarized dual-frequency antenna and a communication terminal. Background Art

[0002] Antenna is an important radio device for transmitting and receiving electromagnetic waves. With the rapid development of mobile satellite communication technology, the market demand for high-performance antenna products is increasing, especially the demand for handheld terminal devices with small size, easy to carry, high sensitivity and high stability is more urgent.

[0003] At present, the antennas of mobile satellite communication terminals on the market are basically cylindrical four-arm spiral antennas, which are large in size, not easy to fold, and cannot adapt to various market scenarios. Summary of the invention

[0004] The embodiments of the present application aim to provide a bidirectional circularly polarized dual-frequency antenna and a communication terminal, aiming to solve the problems that the current satellite communication terminal antennas are large in size, inconvenient to fold, and cannot adapt to various market scenarios.

[0005] To solve the above technical problems, the embodiments of the present application provide the following technical solutions: a bidirectional circularly polarized dual-frequency antenna, comprising: an antenna cavity, a feeding plate, a first radiation plate, a second radiation plate and a feeding port; wherein:

[0006] The feeding plate, the first radiation plate and the second radiation plate are sequentially installed in the antenna cavity from the inside to the outside in a stacked form;

[0007] The feed port is connected to the feed board and is used to receive external input feed and input it into the feed board;

[0008] The feeding board is used to receive power and feed power to the first radiation board and the second radiation board;

[0009] The first radiation plate and the second radiation plate form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the feeding combination resonance.

[0010] Optionally, the antenna cavity includes a bottom plate; a cylinder is arranged at the center of the bottom plate; an inverted convex-shaped arm portion is arranged on each of the four sides of the bottom plate, and two first gaps are formed between each of the inverted convex-shaped arm portion and the bottom plate.

[0011] Optionally, the feeding port includes a left-hand polarized signal input port and a right-hand polarized signal input port, the left-hand polarized signal input port and the right-hand polarized signal input port are isolated from each other in the dual-frequency band, and are used to receive external input feed and input it into the feeding board.

[0012] Optionally, a thickness of the feeding board is smaller than a thickness of the first radiation board and the second radiation board.

[0013] Optionally, the feed board includes a third mounting hole arranged at the center of the feed board, and the third mounting hole is sleeved on the cylinder, so that the feed board is installed in the antenna cavity.

[0014] Optionally, the feed board includes a microstrip bridge printed on its surface; the microstrip bridge includes a first feed post, a second feed post and a microstrip; the microstrip is rectangular, and each microstrip edge constituting the rectangular shape extends a portion of the microstrip outward, wherein the two adjacent extended ends are respectively connected to the left-hand polarization signal input port and the right-hand polarization signal input port, and the other two ends are respectively connected to the first feed post and the second feed post.

[0015] Optionally, the first radiation plate is arranged on the feeding plate; the first radiation plate includes a first mounting hole arranged at the center of the first radiation plate, the first mounting hole is sleeved on the cylinder, and the first radiation plate is installed in the antenna cavity.

[0016] Optionally, the first radiation board includes a first microstrip radiation plate, which is square and used to receive feeding from the microstrip bridge by coupling.

[0017] Optionally, the first radiation plate is provided with a first through hole and a second through hole, respectively, and the first through hole and the second through hole are respectively sleeved on the first feeding pole and the second feeding pole.

[0018] Optionally, the second radiation plate is arranged on the first radiation plate; the first radiation plate includes a second mounting hole arranged at the center of the second radiation plate, the second mounting hole is sleeved on the cylinder, and the second radiation plate is installed in the antenna cavity.

[0019] Optionally, the second radiation plate is provided with a third electrical through hole and a fourth electrical through hole, respectively, and the third electrical through hole and the fourth electrical through hole are respectively sleeved on the first feeding post and the second feeding post, and are respectively in electrical contact with the first feeding post and the second feeding post.

[0020] Optionally, the second radiation board also includes a second microstrip radiation plate, which is square and has a side length smaller than that of the first microstrip radiation plate. The second microstrip radiation plate is in electrical contact with the third electrical via and the fourth electrical via, respectively, to receive power feed from the microstrip bridge.

[0021] Optionally, second slots are provided at four corners of the antenna cavity, and resonance is generated at the second slots at two adjacent corners, and the direction of the resonant electric field is at an angle of 45° with the direction of the electric field of the first microstrip radiation plate and the second microstrip radiation plate.

[0022] Optionally, the first radiation plate and the second radiation plate are both microwave dielectric plates.

[0023] In order to solve the above technical problems, the embodiments of the present application also provide the following technical solutions: a communication terminal, wherein the communication terminal comprises the bidirectional circularly polarized dual-frequency antenna described in any embodiment of the present application.

[0024] Compared with the prior art, the embodiment of the present application provides a bidirectional circularly polarized dual-frequency antenna and a communication terminal, wherein the bidirectional circularly polarized dual-frequency antenna includes an antenna cavity, a feed plate, a first radiating plate, a second radiating plate and a feed port; the feed plate, the first radiating plate and the second radiating plate are installed in the antenna cavity in a stacked form from the inside to the outside; the feed port is connected to the feed plate, receives external input feed and inputs it into the feed plate; the feed plate receives feed and feeds the first radiating plate and the second radiating plate; the first radiating plate and the second radiating plate form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the combined resonance of the feed. Thus, the bidirectional circularly polarized dual-frequency antenna can be small in size, thin in thickness (only 3.5 mm), easy to fold, easy to carry, and high in performance, which can meet the needs of various scenarios in the market, especially the needs of communication terminal equipment with small size, easy to carry, high sensitivity and high stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0026] Figure 1 It is a schematic diagram of the structural decomposition of a bidirectional circularly polarized dual-frequency antenna provided by the present application;

[0027] Figure 2 It is a perspective schematic diagram of the combined structure of a bidirectional circularly polarized dual-frequency antenna provided by the present application;

[0028] Figure 3 It is a structural schematic diagram of an antenna cavity in a bidirectional circularly polarized dual-frequency antenna provided by the present application;

[0029] Figure 4 It is a structural schematic diagram of a feed board in a bidirectional circularly polarized dual-frequency antenna provided by the present application;

[0030] Figure 5 It is a structural schematic diagram of a first radiating plate in a bidirectional circularly polarized dual-frequency antenna provided by the present application;

[0031] Figure 6 It is a structural schematic diagram of a second radiating plate in a bidirectional circularly polarized dual-frequency antenna provided by the present application;

[0032] Figure 7 It is a schematic diagram of an S11 test curve of a bidirectional circularly polarized dual-frequency antenna provided in the present application;

[0033] Figure 8 It is a structural schematic diagram of a communication terminal provided by the present application;

[0034] Fig. 9 This is a schematic diagram of the antenna gain curve of a bidirectional circularly polarized dual-frequency antenna provided by the present application applied to a satellite communication terminal at a high frequency band of 2.17 GHZ frequency;

[0035] Fig.10 This is a schematic diagram of the antenna gain curve of a bidirectional circularly polarized dual-frequency antenna provided by the present application applied to a satellite communication terminal at a low frequency band of 1.98 GHZ.

[0036] Reference numerals:

[0037] Bidirectional circular polarization dual-frequency antenna 1 Antenna cavity 11

[0038] Base plate 111 Cylinder 112

[0039] Inverted convex arm portion 113 First gap 114

[0040] Second gap 115 Resonance electric field direction 116

[0041] Induction magnetic field direction 117 Feed board 12

[0042] Third mounting hole 122 Microstrip bridge 123

[0043] The first feeding post 1231 The second feeding post 1232

[0044] Microstrip 1233 First radiation plate 13

[0045] First microstrip radiation plate 131 First mounting hole 132

[0046] The first through hole 133 and the second through hole 134

[0047] Second radiation plate 14 Second microstrip radiation plate 141

[0048] Second mounting hole 142 Third electrical through hole 143

[0049] Fourth electrical via 144 Feeding port 15

[0050] Left-hand polarization signal input port 151 Right-hand polarization signal input port 152 DETAILED DESCRIPTION

[0051] In order to facilitate the understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on another element or there can be one or more centered elements therebetween. When an element is described as "connected" to another element, it can be directly connected to another element or there can be one or more centered elements therebetween. The orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "bottom" and the like used in this specification is based on the orientation or positional relationship shown in the accompanying drawings, only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" and the like are used only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0052] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this specification and in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0053] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0054] Antenna is an important radio device for transmitting and receiving electromagnetic waves. With the rapid development of mobile satellite communication technology, the market demand for high-performance antenna products is increasing, especially the demand for handheld terminal devices with small size, easy to carry, high sensitivity and high stability is more urgent.

[0055] At present, the antennas of mobile satellite communication terminals on the market are basically cylindrical four-arm spiral antennas, which are large in size, not easy to fold, and cannot adapt to various market scenarios.

[0056] At present, in order to reduce the size of the antenna, a microstrip antenna is generally used. This type of microstrip antenna will encounter the following problems when reducing the size:

[0057] 1. Reducing the reflection reference ground will cause the antenna front-to-back gain ratio and directivity to deteriorate, and the antenna gain will decrease, which cannot meet the needs of satellite terminals. This is because the antenna gain is generated by the antenna's convergence of electromagnetic waves. Metal reflects electromagnetic waves, requiring the length of the reflection surface to be greater than 1 / 2 of the electromagnetic wave wavelength. If the antenna reference ground is close to or less than 1 / 2 of the wavelength, the antenna gain will deteriorate significantly.

[0058] 2. Reducing the thickness of the microstrip antenna will reduce the antenna bandwidth, and the bandwidth requirement of the communication antenna determines the thickness of the microstrip antenna.

[0059] In view of this, the present invention provides a bidirectional circularly polarized dual-frequency antenna, which includes an antenna cavity, a feed plate, a first radiating plate, a second radiating plate and a feed port; the feed plate, the first radiating plate and the second radiating plate are installed in the antenna cavity in a stacked form from the inside to the outside; the feed port is connected to the feed plate, receives external input feed and inputs it into the feed plate; the feed plate receives feed and feeds the first radiating plate and the second radiating plate; the first radiating plate and the second radiating plate form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the combined resonance of the feed. Thus, the bidirectional circularly polarized dual-frequency antenna can be small in size, thin in thickness (only 3.5 mm), easy to fold, easy to carry, and high in performance, which can meet the market's use in a variety of scenarios, especially to meet the needs of communication terminal equipment with small size, easy to carry, high sensitivity and high stability.

[0060] In order to facilitate understanding of the above inventive concept of the present invention, the above inventive concept of the present invention is described in more detail below in conjunction with the accompanying drawings and specific embodiments.

[0061] In one embodiment, Figure 1 and Figure 2 As shown, the present application provides a bidirectional circularly polarized dual-frequency antenna, wherein the bidirectional circular polarization includes a left-hand circular polarization direction and a right-hand circular polarization direction, and the dual frequency includes a receiving frequency band and a transmitting frequency band; the bidirectional circularly polarized dual-frequency antenna 1 includes: an antenna cavity 11, a feeding plate 12, a first radiating plate 13, a second radiating plate 14 and a feeding port 15; wherein:

[0062] The feeding plate 12, the first radiation plate 13 and the second radiation plate 14 are sequentially installed in the antenna cavity 11 from the inside to the outside in a stacked form;

[0063] The feeding port 15 is connected to the feeding board 12 and is used to receive external input power and input it into the feeding board 12;

[0064] The feeding plate 12 is used to receive power and feed power to the first radiation plate 13 and the second radiation plate 14;

[0065] The first radiation plate 13 and the second radiation plate 14 form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the feeding combined resonance.

[0066] In this embodiment, the bidirectional circularly polarized dual-frequency antenna includes an antenna cavity, a feed plate, a first radiating plate, a second radiating plate and a feed port; the feed plate, the first radiating plate and the second radiating plate are installed in the antenna cavity in a stacked form from the inside to the outside; the feed port is connected to the feed plate, receives external input feed and inputs it into the feed plate; the feed plate receives feed and feeds the first radiating plate and the second radiating plate; the first radiating plate and the second radiating plate form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the combined resonance of the feed. Thus, the bidirectional circularly polarized dual-frequency antenna can be small in size, thin in thickness (only 3.5 mm), easy to fold, easy to carry, and high in performance, which can meet the needs of various scenarios in the market, especially the needs of communication terminal equipment with small size, easy to carry, high sensitivity and high stability.

[0067] In one embodiment, Figure 2 and Figure 3 As shown, the antenna cavity 11 is used to install the feed plate 12, the first radiation plate 13 and the second radiation plate 14, so that the feed plate 12, the first radiation plate 13 and the second radiation plate 14 are sequentially installed in the antenna cavity 11 from the inside to the outside in a stacked form.

[0068] The antenna cavity 11 includes: a bottom plate 111; a cylinder 112 is arranged at the center of the bottom plate 111; an inverted convex arm portion 113 is arranged on each of the four sides of the bottom plate 111, and the first gap 114 formed between two adjacent inverted convex arm portions 113 and the bottom plate 111 can be connected together to form a long gap.

[0069] Furthermore, second slots 115 are provided at four corners of the antenna cavity 11 .

[0070] In one embodiment, Figure 4 As shown, the feeding port 15 is connected to the feeding board 12, and is used to receive external input feeding and input it into the feeding board 12. Wherein:

[0071] The feeding port 15 includes a left-hand polarized signal input port 151 and a right-hand polarized signal input port 152 . The left-hand polarized signal input port 151 and the right-hand polarized signal input port 152 are isolated from each other in the dual-frequency band and are respectively used to receive external input feed and input it into the feeding board 12 .

[0072] like Figures 2 to 4 As shown, the left-hand polarization signal input port 151 is fixedly installed in one of the first slots 114 formed between one of the inverted convex-shaped arm portions 113 and the bottom plate 111; the right-hand polarization signal input port 152 is fixedly installed in a first slot 114 formed between the inverted convex-shaped arm portion 113 adjacent to the above-mentioned inverted convex-shaped arm portion 113 and the bottom plate 111, and the two first slots 114 are connected together to form a long slot.

[0073] In one embodiment, Figures 1 to 4 As shown, the feeding board 12 is used to receive power and feed power to the first radiation board 13 and the second radiation board 14 .

[0074] The feeding plate 12 is a microwave dielectric plate, and the thickness of the feeding plate 12 is smaller than the thickness of the first radiation plate 13 and the second radiation plate 14 .

[0075] The feed board 12 includes: a third mounting hole 122 arranged at the center of the feed board 12, the third mounting hole 122 matches the cylinder 112 of the antenna cavity 11, and is used to sleeve the third mounting hole 122 on the cylinder 112, and the feed board 12 is installed in the antenna cavity 11 through the installation cooperation between the third mounting hole 122 and the cylinder 112.

[0076] The feeding board 12 further includes a microstrip bridge 123 printed on its surface, and the microstrip bridge 123 is connected to the feeding port 15 and is used to receive the feeding transmitted from the feeding port 15. Preferably, the microstrip bridge 123 is a microstrip 3DB bridge.

[0077] The microstrip bridge 123 includes: a first feeding post 1231, a second feeding post 1232 and a microstrip 1233; the microstrip 1233 is rectangular, and each microstrip edge constituting the rectangular shape extends a portion of the microstrip outward, wherein the two adjacent extended ends are respectively connected to the left-hand polarization signal input port 151 and the right-hand polarization signal input port 152, and receive external feeding input by the left-hand polarization signal input port 151 and the right-hand polarization signal input port 152; the other two ends are respectively connected to the first feeding post 1231 and the second feeding post 1232.

[0078] Since the conventional circularly polarized antenna feed board is generally arranged on the back of the antenna bottom, if it is installed on the front of the antenna bottom, the electromagnetic field generated by the feed board circuit will interact with the electromagnetic field of the antenna's microstrip radiator, causing the antenna radiator and the feed board circuit to work abnormally. In this embodiment, the feed board 12 is installed inside the antenna cavity 11, which can overcome the defect that the electromagnetic field generated by the feed board 12 circuit will interact with the electromagnetic field of the antenna's microstrip radiator; and the feed board 12 adopts a microstrip bridge solution, which can reduce the thickness of the feed board 12 as much as possible, thereby reducing the thickness of the bidirectional circularly polarized dual-frequency antenna, so that the electric field between the microstrip bridge 123 of the feed board 12 and the reference ground becomes larger, and the electric field difference between the first radiator and the second radiator and the reference ground becomes larger, thereby reducing the interaction between the circuit electromagnetic field of the feed board 12 and the electromagnetic field of the microstrip radiator of the first radiator 13 and the second radiator 14. For conventional circularly polarized antennas, the antenna thickness is reduced, which will also reduce the antenna bandwidth. After reducing the thickness of the bidirectional circularly polarized dual-frequency antenna, the present application can increase the bandwidth by setting the second slots 115 at the four corners of the antenna cavity 11, so that when the bidirectional circularly polarized dual-frequency antenna is working, resonance is generated at the second slots 115 at two adjacent corners, and the direction of the resonant electric field is as follows: Figure 3 As shown in the resonant electric field direction 116, the angle between the electric field directions of the first microstrip radiating plate of the first radiating plate and the second microstrip radiating plate of the second radiating plate of the antenna is 45° (the first microstrip radiating plate of the first radiating plate and the second microstrip radiating plate of the second radiating plate of the antenna are consistent with the directions of the first feeding pole 1231 and the second feeding pole 1232 of the antenna, in the vertical directions of the four sides). The resonant radiation increases the antenna bandwidth.

[0079] In one embodiment, Figures 1 to 5 As shown, the first radiation plate 13 is a microwave dielectric plate. The first radiation plate 13 is disposed on the feeding plate 12 .

[0080] The first radiation plate 13 includes: a first microstrip radiation plate 131 , which is square and is used to receive power feeding from the feeding plate 12 by coupling, specifically receiving power feeding from the microstrip bridge 123 .

[0081] Furthermore, the first radiation plate 13 also includes: a first mounting hole 132 arranged in the center of the first radiation plate 13, the first mounting hole 132 matches the cylinder 112 of the antenna cavity 11, and is used to sleeve the first mounting hole 132 on the cylinder 112, and the first radiation plate 13 is installed in the antenna cavity 11 through the installation cooperation between the first mounting hole 132 and the cylinder 112.

[0082] Furthermore, the first radiation plate 13 is also provided with a first through hole 133 and a second through hole 134, respectively, and the first through hole 133 and the second through hole 134 are respectively sleeved on the first feeding post 1231 and the second feeding post 1232 on the feeding plate 12. The first through hole 133 and the second through hole 134 are only through holes and have no electrical function. The first through hole 133 and the second through hole 134 cannot form an electrical contact with the second microstrip radiation plate 141, and the first through hole 133 and the second through hole 134 do not form an electrical contact with the first feeding post 1231 and the second feeding post 1232. The first radiation plate 13 is better installed on the feeding plate 12 by the installation cooperation of the first through hole 133 and the second through hole 134 with the first feeding post 1231 and the second feeding post 1232, respectively.

[0083] Specifically, the first radiation plate 13 is installed on the antenna cavity 11, including: after the feeding plate 12 is installed in the antenna cavity 11 through the installation cooperation of the third mounting hole 122 and the cylinder 112, the first mounting hole 132, the first through hole 133 and the second through hole 134 of the first radiation plate 13 are respectively sleeved on the cylinder 112 of the antenna cavity 11, the first feeding column 1231 and the second feeding column 1232 of the feeding plate 12, and the first radiation plate 13 is installed on the antenna cavity 11 and the feeding plate 12 through the cooperation of the first mounting hole 132 and the cylinder 112, the first through hole 133 and the first feeding column 1231, and the second through hole 134 and the second feeding column 1232.

[0084] In one embodiment, Figures 1 to 6 As shown, the second radiation plate 14 has the same shape as the first radiation plate 13 . The second radiation plate 14 is a microwave dielectric plate. The second radiation plate 14 is disposed on the first radiation plate 13 .

[0085] The second radiation plate 14 includes: a second mounting hole 142 arranged at the center of the second radiation plate 14, the second mounting hole 142 matches the cylinder 112 of the antenna cavity 11, and is used to sleeve the second mounting hole 142 on the cylinder 112, and the second radiation plate 14 is installed in the antenna cavity 11 through the installation cooperation between the second mounting hole 142 and the cylinder 112.

[0086] Further, the second radiation plate 14 is also provided with a third electrical through hole 143 and a fourth electrical through hole 144, respectively, and the third electrical through hole 143 and the fourth electrical through hole 144 are respectively sleeved on the first feeding post 1231 and the second feeding post 1232 on the feeding plate 12, and are respectively in electrical contact with the first feeding post 1231 and the second feeding post 1232. The feeding provided by the feeding plate 12 is received through the electrical contact between the third electrical through hole 143 and the fourth electrical through hole 144 and the first feeding post 1231 and the second feeding post 1232, respectively.

[0087] Furthermore, the second radiation plate 14 also includes: a second microstrip radiation plate 141, the second microstrip radiation plate 141 is square, the side length of the second microstrip radiation plate 141 is smaller than the side length of the first microstrip radiation plate 131, and the second microstrip radiation plate 141 forms electrical contact with the third electrical via 143 and the fourth electrical via 144 respectively; the second microstrip radiation plate 141 is used to electrically contact with the first feeding column 1231 and the second feeding column 1232 through the third electrical via 143 and the fourth electrical via 144 respectively, and receive the feed provided by the feeding board 12, specifically receiving the feed from the microstrip bridge 123.

[0088] Specifically, the second radiation plate 14 is installed on the antenna cavity 11, including: after the feeding plate 12 and the first radiation plate 13 are respectively installed in the antenna cavity 11, the second mounting hole 142, the third electrical through hole 143 and the fourth electrical through hole 144 of the second radiation plate 14 are respectively sleeved on the cylinder 112 of the antenna cavity 11, the first feeding post 1231 and the second feeding post 1232 of the feeding plate 12, and the second radiation plate 14 is installed on the antenna cavity 11 and the feeding plate 12 through the cooperation of the second mounting hole 142 and the cylinder 112, the third electrical through hole 143 and the first feeding post 1231, and the fourth electrical through hole 144 and the second feeding post 1232, and the third electrical through hole 143 and the fourth electrical through hole 144 are respectively in electrical contact with the first feeding post 1231 and the second feeding post 1232. The third electrical via 143 and the fourth electrical via 144 are in electrical contact with the first feeding post 1231 and the second feeding post 1232 respectively, so that the second microstrip radiation plate 141 receives the feeding provided by the feeding board 12 .

[0089] The first radiation plate 13 and the second radiation plate 14 form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the feeding combined resonance.

[0090] like Figure 7 As shown, Figure 7It is a schematic diagram of an S11 test curve of a bidirectional circularly polarized dual-frequency antenna provided in the present application.

[0091] The left-handed polarized signal is fed into the microstrip bridge 123 of the feeding board 12 through the left-handed polarized signal input port 151, and the two ports of the microstrip bridge 123 connecting the first feeding column 1231 and the second feeding column 1232 output a signal with a phase difference of 90°, which passes through the first feeding column 1231 and the second feeding column 1232, passes through the first radiation board 13, and is connected to the second microstrip radiation plate 141 of the second radiation board 14. The first microstrip radiation plate 131 of the first radiation board 13 receives the feed from the microstrip bridge 123 by coupling, and generates a primary resonance, which resonates in the high frequency band of the bidirectional circularly polarized dual-frequency antenna. The secondary coupling excites the first microstrip radiation plate 131 of the first radiation board 13 to generate a low-frequency resonance, which resonates in the low frequency band of the bidirectional circularly polarized dual-frequency antenna.

[0092] The present application provides a bidirectional circularly polarized dual-frequency antenna, in which a first slot 114 is arranged at the bottom position of four inverted convex-shaped arms 113 of an antenna cavity 11. When the bidirectional circularly polarized dual-frequency antenna is working, the first slot 114 can participate in the resonance of the bidirectional circularly polarized dual-frequency antenna, and an induced magnetic field will be generated along the induced magnetic field direction 117 between the two first slots 114. The induced magnetic field lag of the four inverted convex-shaped arms 113 of the antenna cavity 11 will cause the first microstrip radiating plate 131 of the first radiating plate 13 of the bidirectional circularly polarized dual-frequency antenna 1 and the second microstrip radiating plate 141 of the second radiating plate 14 to produce a resonance with a fixed phase difference. This fixed phase difference is exactly opposite to the reverse radiation phase of the bidirectional circularly polarized dual-frequency antenna 1, and is superimposed on the forward radiation of the bidirectional circularly polarized dual-frequency antenna 1, thereby suppressing the reverse radiation and increasing the gain of the bidirectional circularly polarized dual-frequency antenna 1, thereby achieving the purpose of reducing the size of the bidirectional circularly polarized dual-frequency antenna 1, and the gain of the antenna is not reduced when the overall size of the antenna is reduced.

[0093] Furthermore, the present application installs the feed board 12 inside the antenna cavity 11, which can overcome the defect that the existing feed board is installed on the front of the bottom of the antenna, so that the electromagnetic field generated by the feed board 12 circuit will interact with the electromagnetic field of the antenna's microstrip radiator; and the feed board 12 adopts a microstrip bridge solution, which can minimize the thickness of the feed board 12, thereby reducing the thickness of the bidirectional circularly polarized dual-frequency antenna, so that the electric field between the microstrip bridge 123 of the feed board 12 and the reference ground becomes larger, and the electric field difference between the first radiating plate and the second radiating plate and the reference ground becomes larger, thereby reducing the interaction between the circuit electromagnetic field of the feed board 12 and the electromagnetic field of the microstrip radiators of the first radiating plate 13 and the second radiating plate 14.

[0094] In addition, the bidirectional circularly polarized dual-frequency antenna of the present application can increase the bandwidth by setting the second slots 115 at the four corners of the antenna cavity 11 after reducing the thickness of the bidirectional circularly polarized dual-frequency antenna, so that when the bidirectional circularly polarized dual-frequency antenna is working, resonance is generated at the second slots 115 at two adjacent corners, and the direction of the resonant electric field is as follows: Figure 3 As shown in the resonant electric field direction 116, the angle between the electric field directions of the first microstrip radiating plate of the first radiating plate and the second microstrip radiating plate of the second radiating plate of the antenna is 45° (the first microstrip radiating plate of the first radiating plate of the antenna and the second microstrip radiating plate of the second radiating plate of the antenna are consistent with the directions of the first feeding pole 1231 and the second feeding pole 1232 of the antenna, in the vertical directions of the four sides). The resonant radiation increases the antenna bandwidth and can solve the problem that the existing conventional circularly polarized antenna will reduce the antenna bandwidth as the antenna thickness is reduced.

[0095] Based on the same concept, in one embodiment, Figure 8 As shown, the present application provides a communication terminal, which includes the bidirectional circularly polarized dual-frequency antenna 1 described in any of the above embodiments.

[0096] In this embodiment, the bidirectional circularly polarized dual-frequency antenna 1 is consistent with the bidirectional circularly polarized dual-frequency antenna 1 described in any of the above embodiments. The specific structure and function can refer to the bidirectional circularly polarized dual-frequency antenna 1 described in any of the above embodiments, which will not be repeated here.

[0097] In this embodiment, the communication terminal includes a bidirectional circularly polarized dual-frequency antenna, and the bidirectional circularly polarized dual-frequency antenna includes an antenna cavity, a feed plate, a first radiating plate, a second radiating plate and a feed port; the feed plate, the first radiating plate and the second radiating plate are installed in the antenna cavity in a stacked form from the inside to the outside; the feed port is connected to the feed plate, receives external input feed and inputs it into the feed plate; the feed plate receives feed and feeds the first radiating plate and the second radiating plate; the first radiating plate and the second radiating plate form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the feed combination resonance. Thus, the bidirectional circularly polarized dual-frequency antenna can be small in size, thin in thickness (only 3.5 mm), easy to fold, easy to carry, and high in performance, which can meet the market's use in a variety of scenarios, especially to meet the needs of communication terminal equipment with small size, easy to carry, high sensitivity and high stability.

[0098] It should be noted that the above-mentioned communication terminal embodiment and the bidirectional circularly polarized dual-frequency antenna embodiment belong to the same concept. The specific implementation process is detailed in the bidirectional circularly polarized dual-frequency antenna embodiment, and the technical features in the bidirectional circularly polarized dual-frequency antenna embodiment are correspondingly applicable in the communication terminal embodiment, which will not be repeated here.

[0099] The technical scheme and technical effects of the present application are described in detail below through specific embodiments. The following embodiments are only some embodiments of the present application and do not specifically limit the present application.

[0100] The present application provides a bidirectional circularly polarized dual-frequency antenna, which is applied to a large S-band (TX frequency: 1980-2010MHZ, RX frequency: 2170-2200MHZ) satellite communication terminal with a diameter of 15mm. The performance of the satellite communication terminal using the bidirectional circularly polarized dual-frequency antenna is tested, and the test results are as follows: Fig. 9 , Fig.10 , as shown in Table 1 and Table 2.

[0101] Fig. 9 This is a schematic diagram of the antenna gain curve of a bidirectional circularly polarized dual-frequency antenna provided by the present application applied to a satellite communication terminal at a high frequency band of 2.17 GHZ.

[0102] Fig.10 This is a schematic diagram of the antenna gain curve of a bidirectional circularly polarized dual-frequency antenna provided by the present application applied to a satellite communication terminal at a low frequency band of 1.98 GHZ.

[0103] From above Fig. 9 , Fig.10 As shown in Tables 1 and 2, the bidirectional circularly polarized dual-frequency antenna provided in the present application is applied to a satellite communication terminal. After performance testing of the satellite communication terminal, its low-frequency and high-frequency properties are relatively stable, which can meet the needs of high-sensitivity and high-stability communication terminal equipment.

[0104] Table 1: Statistics of high frequency band detection results of dual-frequency antenna

[0105]

[0106] Table 2: Statistics of dual-band antenna low-frequency detection results

[0107]

[0108] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Under the concept of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present application as described above, which are not provided in detail for the sake of simplicity. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A bidirectional circularly polarized dual-frequency antenna, characterized in that: The bidirectional circular polarization includes a left-hand circular polarization direction and a right-hand circular polarization direction, and the dual frequency includes a receiving frequency band and a transmitting frequency band; The bidirectional circularly polarized dual-frequency antenna comprises: an antenna cavity, a feeding plate, a first radiation plate, a second radiation plate and a feeding port; wherein: The feeding plate, the first radiation plate and the second radiation plate are sequentially installed in the antenna cavity from the inside to the outside in a stacked form; The feeding port comprises a left-hand polarized signal input port and a right-hand polarized signal input port, wherein the left-hand polarized signal input port and the right-hand polarized signal input port are isolated from each other in the dual-frequency band, and are used to receive external input feed and input it into the feeding board; The feed board is used to receive power feed and feed power to the first radiation board and the second radiation board; the feed board includes a microstrip bridge printed on its surface; the microstrip bridge includes a first feed post, a second feed post and a microstrip; the microstrip is rectangular, and each microstrip edge constituting the rectangular shape extends a portion of the microstrip outward, wherein the two adjacent ends of the extension are respectively connected to the left-handed polarization signal input port and the right-handed polarization signal input port, and the other two ends are respectively connected to the first feed post and the second feed post; The antenna cavity comprises a bottom plate, an inverted convex U-shaped arm portion is arranged on each of the four sides of the bottom plate, two first gaps are formed between each of the inverted convex U-shaped arm portion and the bottom plate, and second gaps are arranged at the four corners of the antenna cavity; The first radiation plate and the second radiation plate form two resonant frequencies of the bidirectional circularly polarized dual-frequency antenna according to the feeding combined resonance.

2. The bidirectional circularly polarized dual-frequency antenna according to claim 1, characterized in that: A cylinder is arranged at the center of the bottom plate.

3. The bidirectional circularly polarized dual-frequency antenna according to claim 1, characterized in that: The thickness of the feeding board is smaller than the thickness of the first radiation board and the second radiation board.

4. The bidirectional circularly polarized dual-frequency antenna according to claim 2, characterized in that: The feed board comprises a third mounting hole arranged at the center of the feed board, the third mounting hole is sleeved on the cylinder, and the feed board is mounted in the antenna cavity.

5. The bidirectional circularly polarized dual-frequency antenna according to claim 2, characterized in that: The first radiation plate is arranged on the feeding plate; the first radiation plate comprises a first mounting hole arranged at the center of the first radiation plate, the first mounting hole is sleeved on the cylinder, and the first radiation plate is installed in the antenna cavity.

6. The bidirectional circularly polarized dual-frequency antenna according to claim 2, characterized in that: The first radiation board includes a first microstrip radiation plate, which is square and used for receiving feeding from the microstrip bridge by coupling.

7. The bidirectional circularly polarized dual-frequency antenna according to claim 1, characterized in that: The first radiation plate is provided with a first through hole and a second through hole, respectively. The first through hole and the second through hole are sleeved on the first feeding post and the second feeding post, respectively.

8. The bidirectional circularly polarized dual-frequency antenna according to claim 6, characterized in that: The second radiation plate is arranged on the first radiation plate; the first radiation plate comprises a second mounting hole arranged at the center of the second radiation plate, the second mounting hole is sleeved on the cylinder, and the second radiation plate is installed in the antenna cavity.

9. The bidirectional circularly polarized dual-frequency antenna according to claim 8, characterized in that: The second radiation plate is provided with a third electrical through hole and a fourth electrical through hole, respectively. The third electrical through hole and the fourth electrical through hole are respectively sleeved on the first feeding post and the second feeding post, and are respectively in electrical contact with the first feeding post and the second feeding post.

10. The bidirectional circularly polarized dual-frequency antenna according to claim 9, characterized in that: The second radiation plate also includes a second microstrip radiation plate, which is square and has a side length smaller than that of the first microstrip radiation plate. The second microstrip radiation plate is in electrical contact with the third electrical via and the fourth electrical via, respectively, and receives power feed from the microstrip bridge.

11. The bidirectional circularly polarized dual-frequency antenna according to claim 10, characterized in that: Resonance is generated at the second gaps of two adjacent corners, and the direction of the resonant electric field is at an angle of 45° with the direction of the electric field of the first microstrip radiation plate and the second microstrip radiation plate.

12. The bidirectional circularly polarized dual-frequency antenna according to claim 1, characterized in that: The first radiation plate and the second radiation plate are both microwave dielectric plates.

13. A communication terminal, characterized in that: The communication terminal comprises the bidirectional circularly polarized dual-frequency antenna as described in any one of claims 1 to 12.

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