Dual-frequency common-caliber antenna radiation unit and dual-frequency common-caliber antenna

Abstract

The invention provides a dual-frequency common-caliber antenna radiation unit and a dual-frequency common-caliber antenna, and relates to the communication and antenna technology, and each radiation unit comprises a K-frequency-band folded dipole, four Ka-frequency-band microstrip patches, and two groups of feed baluns in orthogonal layout. The Ka frequency band microstrip patch is coupled with the feed network layer through two H-shaped Ka frequency band coupling gaps which are arranged in an orthogonal mode, an orthogonal feed balun is adopted to achieve selectable K frequency band dual-linear polarization, left-hand circular polarization or right-hand circular polarization, and an orthogonal H-shaped gap is adopted to achieve selectable Ka frequency band dual-linear polarization, left-hand circular polarization or right-hand circular polarization. The dual-frequency common-caliber antenna comprises an antenna layer, a feed network layer, a strip line and a waveguide switching layer, the antenna layer comprises radiation units in a periodic array, and through the technical means of bridging, vertical conductive via holes and the like, the number of layers of PCBs is reduced, meanwhile, the high-density feed network layout is achieved, and the overall performance of the antenna is improved. The K frequency band / Ka frequency band common aperture design and the polarization-selectable multi-polarization application are effectively realized.

Description

Technical Field

[0001] The present application belongs to the field of communication technology and relates to a dual-frequency co-aperture antenna, and specifically to a dual-frequency co-aperture antenna radiation unit and a dual-frequency co-aperture antenna. Background Art

[0002] Dual-frequency co-aperture antennas are widely used in modern communication systems, especially in full-duplex communications, such as satellite communications and mobile communications. They are a widely used method to effectively reduce the number of antennas, improve system integration, and reduce antenna costs.

[0003] A common method to achieve dual-frequency co-aperture is to use the same broadband radiating unit or aperture, such as parabolic antenna, waveguide horn array, etc.

[0004] Although broadband radiating units or apertures solve the problem of common apertures, they often lead to the deterioration of other performances. For example, dual-frequency parabolic antennas require a complex dual-feed structure and cannot achieve optimal efficiency in both operating frequency bands, requiring the sacrifice of some performance. In addition, the dual-frequency parabolic structure is bulky, has a high profile, and has high platform requirements. For example, the waveguide horn array is limited by the spacing between array elements, and it is very easy to produce coral petals in the high-frequency band, which greatly deteriorates the performance and seriously interferes with communications in other directions.

[0005] Other dual-frequency co-aperture methods include stacked design and staggered layout, which place radiating units of different frequency bands in the same physical aperture. The challenge faced by this type of design is how to achieve high isolation in the same physical aperture and reduce the mutual interference between the performance of the two frequency bands. And achieving polarization-selective design is also a very severe challenge for the layout of the feed network.

[0006] Currently, dual-band co-aperture antennas that adopt a stacked design and staggered layout scheme are mainly concentrated in low-frequency bands, such as the L-band; while in high-frequency bands, such as the K-band and Ka-band, there are fewer executable solutions.

[0007] In general, dual-band parabolic antennas and waveguide horn arrays perform poorly in the K-band / Ka-band, while dual-band co-aperture antennas with a stacked design and staggered layout scheme face many challenges in multi-polarization and high-frequency band applications. Summary of the invention

[0008] In response to the problems that the radiation performance of K / Ka dual-frequency co-aperture antennas is prone to mutual interference, the layout of the feeding network is difficult, and multi-polarization is difficult to achieve, the present application provides a dual-frequency co-aperture antenna radiation unit and a dual-frequency co-aperture antenna, which effectively realizes the K / Ka dual-frequency co-aperture design and polarization-selective multi-polarization application, and provides a low-profile, broadband, high-aperture efficiency compact K / Ka dual-frequency co-aperture satellite terminal antenna solution for satellite communications.

[0009] In order to achieve the above object, the present invention adopts the following technologies: A dual-frequency common-aperture antenna radiating unit is arranged in an antenna layer of the antenna in a periodic array, and each radiating unit includes: A K-band folded dipole located on the top surface of the antenna layer; Four Ka-band microstrip patches located in the middle interlayer of the antenna layer and evenly distributed around the K-band folded dipole; and Two groups of feeding baluns are arranged orthogonally and located in the middle layer of the antenna layer, and the feeding baluns are connected to the K-band folded oscillator through conductive vias; The feed balun is coupled with the feed network layer under the antenna layer in the antenna through the H-type K-band coupling slot. When the two sets of feed baluns are fed with the same phase, K-band dual linear polarization is realized. When 90° phase difference feeding is used, K-band left-hand circular polarization or right-hand circular polarization is realized. Each Ka-band microstrip patch is coupled to the feeding network layer through two orthogonally arranged H-type Ka-band coupling slots. When the two H-type Ka-band coupling slots are fed with the same phase, Ka-band dual-linear polarization is achieved. When 90° phase difference feeding is used, Ka-band left-hand circular polarization or right-hand circular polarization is achieved. The H-type K-band coupling slot and the H-type Ka-band coupling slot are located in an H-type coupling slot array arranged on the bottom surface of the antenna layer or the top surface of the feed network layer.

[0010] Furthermore, the K-band folded oscillator is a cross-shaped ring structure, including four ring structures that are arranged in a circular array and connected together to form a cross shape, and has filtering characteristics for Ka-band electromagnetic signals.

[0011] Furthermore, each group of feed baluns includes a feed balun upper structure and a feed balun lower structure. Along the height direction of the antenna layer, the feed balun upper structure is arranged higher than the feed balun lower structure. One end of the feed balun upper structure is a 180° phase feed line, and the other end is connected to the floor layer in the antenna layer through a ground via. One end of the feed balun lower structure is a 0° phase feed line, and the other end is coupled with the feed network layer through an H-type K-band coupling gap. Furthermore, the K-band folded oscillator is connected to two 0° phase feeding lines and two 180° phase feeding lines through four conductive vias.

[0012] Furthermore, the K-band folded oscillator corresponds to two independent K-band electromagnetic transmission paths. When used to receive signals, one path passes through the K-band folded oscillator, a group of feeding baluns, and an H-type K-band coupling slot in sequence, and the other path passes through the K-band folded oscillator, another group of feeding baluns, and an H-type K-band coupling slot in sequence. The path used for transmitting signals is opposite to the path used for receiving signals.

[0013] Furthermore, the length direction of the ring structure is arranged at a predetermined angle with the side of the antenna layer, and the Ka-band microstrip patches are respectively located in the length direction of the ring structure.

[0014] Furthermore, each Ka-band microstrip patch includes an upper microstrip patch unit and a lower microstrip patch unit which are arranged at intervals along the layer height direction of the antenna.

[0015] Furthermore, a circle of grounding conductive holes is arrayed on the periphery of the edge of the upper microstrip patch unit and the lower microstrip patch unit, and the grounding conductive holes are connected to the floor layer in the antenna layer.

[0016] Furthermore, each Ka-band microstrip patch corresponds to two independent Ka-band electromagnetic transmission paths. When used to transmit signals, one of the paths passes through one of the H-type Ka-band coupling gaps, the lower microstrip patch unit, and the upper microstrip patch unit in sequence, and the other path passes through another H-type Ka-band coupling gap, the lower microstrip patch unit, and the upper microstrip patch unit in sequence. The path used for receiving signals is opposite to the path used for transmitting signals.

[0017] A dual-frequency co-aperture antenna comprises an antenna layer, a feed network layer, a strip line and a waveguide switching layer stacked from top to bottom, wherein the antenna layer comprises the dual-frequency co-aperture antenna radiation unit.

[0018] Furthermore, the feed network layer includes a plurality of mutually isolated multi-stage H-type stripline feed networks, and the end of the multi-stage H-type stripline feed network has an electrical coupling structure for electrically coupling with an H-type coupling slot array provided on the bottom surface of the antenna layer or the top surface of the feed network layer to conduct signals with the antenna layer, and the input / output interlayer coupling slots of the multi-stage H-type stripline feed network connect the stripline and the waveguide transition layer.

[0019] Furthermore, the feeding network layer includes four mutually isolated multi-stage H-type stripline feeding networks, namely a first H-type feeding network, a second H-type feeding network, a third H-type feeding network, and a fourth H-type feeding network; the signal transmission lengths of the first H-type feeding network and the second H-type feeding network are the same, and they are two orthogonal polarization feeding networks in the Ka band; the signal transmission lengths of the third H-type feeding network and the fourth H-type feeding network are the same, and they are two orthogonal polarization feeding networks in the K band.

[0020] Furthermore, the feeding network layer includes two PCB layers, the first H-type feeding network and the third H-type feeding network are located on one of the PCB layers, and the second H-type feeding network and the fourth H-type feeding network are located on the other PCB layer; a bridge structure is adopted at the intersection of the transmission branches of different multi-level H-type stripline feeding networks in the same PCB layer, and the transmission branch line of one of the multi-level H-type stripline feeding networks at the intersection is disconnected, and vertical conductive through holes are respectively arranged at the two ends of the disconnection, and the two vertical conductive through holes are connected to the same transmission bridge line located on the other PCB layer.

[0021] Furthermore, the stripline and waveguide transition layer includes a plurality of transition units, and the transition units include signal transmission striplines and coupling patches in different interlayers. One end of the signal transmission stripline is connected to the input / output end of the multi-stage H-type stripline feeding network through an interlayer coupling gap, and the other end is connected to the coupling patch through an H-type microstrip coupling gap for signal conduction.

[0022] Furthermore, the multiple switching units include at least one pair of K-band switching units and at least one pair of Ka-band switching units; a circle of first grounding holes arranged in a rectangular ring is provided on the circumference of the coupling patch, and the first grounding holes are connected to the ground layer in the strip line and waveguide switching layer; in the K-band switching unit, the rectangular area surrounded by the first grounding holes serves as a K-band input / output port; in the Ka-band switching unit, the rectangular area surrounded by the first grounding holes serves as a Ka-band input / output port.

[0023] Furthermore, second grounding holes are arranged in arrays on both sides of the signal transmission stripline and the periphery of the coupling patch, and the second grounding holes are connected to the ground layer in the stripline and waveguide transition layer.

[0024] Furthermore, the H-type microstrip coupling gap includes a straight segment and an open rectangular ring symmetrically and vertically connected to both ends of the straight segment in the length direction, the opening of the open rectangular ring faces outward and is located on the extension line of the straight segment along the length direction; in the layer height direction of the strip line and the waveguide transition layer, the projection of the signal transmission strip line intersects vertically with the projection of the straight segment.

[0025] Furthermore, the antenna layer, the feed network layer, the strip line and the waveguide switching layer are respectively implemented by multi-layer PCB boards.

[0026] The beneficial effects of the present invention are: 1. The combination of heterogeneous folded vibrators and double-layer microstrip patches, and the staggered layout up and down, can realize the design of common-aperture radiation units in the K / Ka band. By optimizing the folded vibrator structure, the re-radiation of Ka-band electromagnetic signals on the K-band antenna can be suppressed, ensuring the performance of the Ka band. In addition, the use of H-shaped gaps to achieve electromagnetic coupling reduces the difficulty of PCB processing; 2. Two sets of orthogonal feeding baluns are used to realize the optional dual linear polarization, left-hand circular polarization or right-hand circular polarization in the K band, and two orthogonal H-type Ka band coupling slots are used to realize the optional dual linear polarization, left-hand circular polarization or right-hand circular polarization in the Ka band, which can be adapted according to application needs. The wiring density of the single-layer feeding network and the staggered layout of the orthogonal polarization feeding network are reduced by bridging, vertical conductive vias and other technical means, so as to achieve a high-density feeding network layout while reducing the number of PCB layers. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a diagram of the overall structure of the dual-frequency common-aperture antenna of an embodiment of the present application.

[0028] Figure 2 It is a schematic diagram of the cross section of the radiation unit and the transmission path of an embodiment of the present application.

[0029] Figure 3 It is a schematic diagram of the structure of the K-band folded oscillator and the Ka-band microstrip patch in the radiation unit of the embodiment of the present application.

[0030] Figure 4 It is the antenna gain simulation result with and without the folded dipole in the embodiment of the present application.

[0031] Figure 5 It is a schematic diagram of the structure of the K-band folded oscillator and the feeding balun in the radiation unit of the embodiment of the present application.

[0032] Figure 6 It is a partial top view of the H-type coupling slot array according to an embodiment of the present application.

[0033] Figure 7 It is a top view of the feed network layer of an embodiment of the present application.

[0034] Figure 8 It is a schematic diagram of the bridging structure of an embodiment of the present application.

[0035] Fig. 9 It is a schematic diagram of the structure of the switching unit of an embodiment of the present application.

[0036] Fig.10 This is a diagram of the overall structure of the dual-frequency co-aperture antenna from another perspective of an embodiment of the present application.

[0037] Fig.11 It is a simulation result diagram of the stripline and waveguide transition layer in the K band of the embodiment of the present application.

[0038] Fig.12 It is a simulation result diagram of the stripline and waveguide transition layer in the Ka band of an embodiment of the present application.

[0039] Figure numerals: 100a-antenna layer, 100b-feed network layer, 100c-strip line and waveguide transition layer, 111-K-band folded oscillator, 111a-ring structure, 112-Ka-band microstrip patch, 112a-upper microstrip patch unit, 112b-lower microstrip patch unit, 113a-first Ka-band path, 113b-second Ka-band path, 114a-first K-band path, 114b-second K-band path, 121-conductive via, 122-feed balun, 122a-feed balun upper structure, 122b-feed balun lower structure, 122c-180° phase feed line, 122d-0° phase feed line, 123-ground via, 124-floor layer, 125-H-type Ka-band coupling slot, 126-H-type K-band coupling slot, 130-H-type coupling slot array, 140-first H-type feeding network, 142-second H-type feeding network, 144-third H-type feeding network, 146-fourth H-type feeding network, 148-electrical coupling structure, 151-transmission branch line, 152-vertical conductive through hole, 153-transmission bridge line, 170-second grounding hole, 171-signal transmission stripline, 172-coupling patch, 173-H-type microstrip coupling slot, 173a-straight section, 173b-open rectangular ring, 174-first grounding hole, 175-rectangular area, 181-K-band input / output port, 182-Ka-band input / output port. DETAILED DESCRIPTION

[0040] To make the objectives, technical solutions and advantages of the embodiments of the present invention more clear, the implementation modes of the present invention are described in detail below with reference to the accompanying drawings. However, the embodiments described in the present invention are only part of the embodiments of the present invention, rather than all the embodiments.

[0041] In one aspect of an embodiment of the present application, a dual-frequency common-aperture antenna radiating unit is provided, such as Figure 1-Figure 3 , Figure 5 As shown, the antenna layer 100a of the antenna is arranged in a periodic array, and each radiating unit includes: a K-band folded dipole 111 located on the top surface of the antenna layer 100a, four Ka-band microstrip patches 112 located in the middle layer of the antenna layer 100a and evenly distributed on the sides of the K-band folded dipole 111, and two groups of feeding baluns 122 arranged in an orthogonal manner and located in the middle layer of the antenna layer 100a.

[0042] The feeding balun 122 is connected to the K-band folded oscillator 111 through the conductive via 121, and is coupled with the feeding network layer 100b below the antenna layer 100a in the antenna through the H-type K-band coupling slot 126. When the feeding balun 122 adopts the same phase feeding, the K-band dual linear polarization is realized, and when the 90° phase difference feeding is adopted, the K-band left-hand circular polarization or right-hand circular polarization is realized.

[0043] Each Ka-band microstrip patch 112 is coupled to the feeding network layer 100b through two orthogonally arranged H-type Ka-band coupling slots 125. When the H-type Ka-band coupling slots 125 are fed with the same phase, Ka-band dual-linear polarization is achieved, and when 90° phase difference feeding is used, Ka-band left-hand circular polarization or right-hand circular polarization is achieved.

[0044] like Figure 6 As shown, the H-type K-band coupling slot 126 and the H-type Ka-band coupling slot 125 are located in the H-type coupling slot array 130; Figure 1 As shown, the H-type coupling slot array 130 is located on the bottom surface of the antenna layer 100a or the top surface of the feed network layer 100b. Specifically, the size, spacing, relative position, etc. of each slot in the H-type coupling slot array 130 are set according to the operating frequency. The H-type coupling slot array 130 is used for coupling conduction, which can reduce the processing difficulty of the PCB board layer and allow each functional layer to be processed independently.

[0045] like Figure 3 and Figure 5 As shown, a structural example of the K-band folded oscillator 111 is a cross-shaped ring structure, including four ring structures 111a in a circular array and connected together to form a cross shape, which can optimize the suppression of the re-radiation of the Ka-band electromagnetic signal on the K-band folded oscillator 111 and has filtering characteristics for the Ka-band electromagnetic signal.

[0046] The two groups of feeding baluns 122 are arranged orthogonally and staggered with each other. Figure 5 As shown, the feed balun 122 adopts a stripline structure, and each group includes a feed balun upper structure 122a and a feed balun lower structure 122b. Along the layer height direction of the antenna layer 100a, the feed balun upper structure 122a is arranged higher than the feed balun lower structure 122b. One end of the feed balun upper structure 122a is a 180° phase feed line 122c, and the other end is connected to the floor layer 124 in the antenna layer 100a through a ground via 123. One end of the feed balun lower structure 122b is a 0° phase feed line 122d, and the other end is coupled with the feed network layer 100b through an H-type K-band coupling slot 126; the K-band folded oscillator 111 is connected to two 0° phase feed lines 122d and two 180° phase feed lines 122c through four conductive vias 121 to achieve equal amplitude feeding of 0° and 180°. Since the feed balun upper structure 122a is higher than the feed balun lower structure 122b, the length of the two conductive vias 121 connecting the feed balun upper structure 122a is different from the length of the two conductive vias 121 connecting the feed balun lower structure 122b, forming an up-and-down staggered layout structure.

[0047] Specifically, the lengths of the feed balun upper structure 122a and a feed balun lower structure 122b are reasonably set according to the dielectric constant of the PCB board layer and the operating frequency.

[0048] like Figure 2 As shown, the K-band folded oscillator 111 corresponds to two independent K-band electromagnetic transmission paths. When receiving a signal, one of the paths passes through the K-band folded oscillator 111, a group of feeding baluns 122, and an H-type K-band coupling slot 126 in sequence. Figure 2 The first K-band path 114a shown; the other path passes through the K-band folded oscillator 111, another set of feeding baluns 122, and the H-type K-band coupling slot 126 in sequence. Figure 2 The second K-band path 114b is shown. Figure 2 Only the path for receiving signals is shown. After the signal is received by the K-band folded oscillator 111, it is transmitted through the first K-band path 114a and the second K-band path 114b, respectively, corresponding to the incoming wave signals in two orthogonal polarization directions. The path for transmitting signals is opposite to the path for receiving signals.

[0049] A particularly desirable radiation characteristic is that the radiation performance of the high-band antenna located below is not distorted or deteriorated when the low-band radiating element is blocked. Such radiation performance includes, but is not limited to: axial gain, radiation pattern, axial ratio, cross-polarization isolation, etc. Figure 1 and Figure 3 As shown, the sides of the K-band folded oscillator 111 are not parallel to the side of the antenna layer 100a, but are arranged at a certain angle. The length direction of the ring structure 111a is arranged at a predetermined angle with the side of the antenna layer 100a, preferably at an angle of 45°. The Ka-band microstrip patches 112 are respectively located in the length direction of the ring structure 111a. Specifically, in the example Figure 3 In the coordinate system shown, in the XY plane, the four Ka-band microstrip patches 112 are respectively located in four quadrants centered on the K-band folded oscillator 111. Based on this structure, Figure 4 The figure shows the simulation results of the Ka-band axial gain with and without the K-band folded oscillator 111. Figure 4 The ordinate represents the axial gain (dBi), the abscissa represents the operating frequency (GHz), line 1002 shows the Ka-band axial gain when the K-band folded oscillator 111 does not exist or is not included, and line 1004 shows the Ka-band axial gain when the K-band folded oscillator 111 does not exist or is not included. It can be seen that, under the common aperture condition, the structure and layout angle of the K-band folded oscillator 111 used in this example, as well as the position setting method of the Ka-band microstrip patch 112, have little effect on the Ka-band axial gain, and the entire operating frequency band is controlled below 0.4dB.

[0050] like Figure 2 and Figure 3 As shown, each Ka-band microstrip patch 112 includes an upper microstrip patch unit 112a and a lower microstrip patch unit 112b arranged at intervals along the layer height direction of the antenna layer 100a. The upper microstrip patch unit 112a is located above the lower microstrip patch unit 112b.

[0051] Preferably, a circle of grounding conductive holes is arrayed on the periphery of the edge of the upper microstrip patch unit 112a and the lower microstrip patch unit 112b, and the grounding conductive holes are connected to the floor layer 124 in the antenna layer 100a to share the floor with the K-band folded oscillator 111. The grounding conductive holes are provided to isolate the mutual interference between the feed balun 122 and the Ka-band microstrip patch 112, thereby achieving electrical isolation.

[0052] like Figure 2 As shown, each Ka-band microstrip patch 112 corresponds to two independent Ka-band electromagnetic transmission paths. When transmitting a signal, one of the paths passes through one of the H-type Ka-band coupling gaps 125, the lower microstrip patch unit 112b, and the upper microstrip patch unit 112a in sequence. Figure 2 The first Ka-band path 113a shown; the other path passes through another H-type Ka-band coupling gap 125, the lower microstrip patch unit 112b, and the upper microstrip patch unit 112a in sequence, as shown in FIG. Figure 2 The second Ka-band path 113b is shown. Figure 2 Only the path for transmitting signals is shown, and the transmitting signals are transmitted through two orthogonal H-type Ka-band coupling slots 125, and are respectively transmitted after passing through the first Ka-band path 113a and the second Ka-band path 113b, thereby realizing the input of two orthogonally polarized electromagnetic signals. The path for receiving signals is opposite to the path for transmitting signals.

[0053] Another aspect of the present application is to provide a dual-frequency common aperture antenna, which is implemented using a multi-layer PCB board structure, such as Figure 1 and Fig.10 As shown, the antenna layer 100a, the feed network layer 100b, and the stripline and waveguide transition layer 100c are stacked from top to bottom, and the feed network layer 100b is arranged between the antenna layer 100a and the stripline and waveguide transition layer 100c. Although not shown, each layer of the antenna layer 100a, the feed network layer 100b, and the stripline and waveguide transition layer 100c includes one or more PCB sublayers, and preferably, each is implemented by a multi-layer PCB board.

[0054] The antenna layer 100a, the feed network layer 100b, the strip line and the waveguide transition layer 100c are electrically connected through coupling slots. For example, the antenna layer 100a and the feed network layer 100b can be electrically connected through an H-shaped coupling slot array 130 located on the bottom surface of the antenna layer 100a or the top surface of the feed network layer 100b. Different vias are used inside each layer to achieve signal conduction and electromagnetic shielding.

[0055] The antenna layer 100a includes the dual-frequency co-aperture antenna radiating unit described in the above implementation.

[0056] As an optional example, the periodic array formed by the antenna radiating unit in the antenna layer 100a includes 4×4 K-band folded oscillators 111 and 8×8 Ka-band microstrip patches 112. The array of K-band folded oscillators 111 corresponds to the K-band antenna radiating array, and the array of Ka-band microstrip patches 112 corresponds to the Ka-band antenna radiating array. The period of the Ka-band antenna radiating array is half of the period of the K-band antenna radiating array. Specifically, the array scale can be easily adjusted and expanded according to application requirements.

[0057] like Figure 7 As shown, the feed network layer 100b includes a plurality of mutually isolated multi-stage H-type stripline feed networks, and the end of the multi-stage H-type stripline feed network has an electrical coupling structure 148 for electrically coupling with an H-type coupling slot array 130 provided on the bottom surface of the antenna layer 100a or the top surface of the feed network layer 100b, so as to conduct signals with the antenna layer 100a, and the input / output interlayer coupling slots of the multi-stage H-type stripline feed network connect the stripline and the waveguide transition layer 100c.

[0058] As a specific example, the feed network layer 100 b includes four mutually isolated multi-stage H-type stripline feed networks, namely a first H-type feed network 140 , a second H-type feed network 142 , a third H-type feed network 144 , and a fourth H-type feed network 146 .

[0059] The first H-type feeding network 140 and the second H-type feeding network 142 have the same signal transmission length, which are two orthogonal polarization feeding networks in the Ka band; the third H-type feeding network 144 and the fourth H-type feeding network 146 have the same signal transmission length, which are two orthogonal polarization feeding networks in the K band. By setting the same signal transmission length, signal delays of each path caused by different path lengths can be avoided.

[0060] In the prior art, a separate PCB layer is required for the feeding network of each polarization direction, and as the number of feeding networks increases, the number of required PCB layers also increases. For example, a dual-frequency dual-polarization common-aperture antenna requires four feeding networks, so the antenna should include four separate feeding network PCB layers. However, the introduction of more PCB layers will cause more potential signal losses, resulting in higher costs and higher manufacturing difficulties, as well as potential alignment risks. Preferably, compared to the existing method of laying out each feeding network on a PCB layer, the feeding network layer 100b in this example can adopt a solution that includes only two PCB layers, the first H-type feeding network 140 and the third H-type feeding network 144 are located on one of the PCB layers, and the second H-type feeding network 142 and the fourth H-type feeding network 146 are located on another PCB layer, thereby reducing the number of required PCB layers.

[0061] In order to solve this problem caused by reducing the number of PCB layers, preferably, a bridge structure is used at the intersection of the transmission branches of different multi-level H-type stripline feeding networks in the same PCB layer, such as Figure 8 As shown, the transmission branch line 151 of one of the multi-level H-type stripline feeding networks at the intersection is disconnected, and vertical conductive through holes 152 are respectively set at the two ends of the disconnection, and the two vertical conductive through holes 152 are connected to the same transmission bridge line 153 located on another PCB layer, so that the transmission branch line 151 of another multi-level H-type stripline feeding network can pass from below or above the transmission bridge line 153 (determined according to the relationship between the PCB layer where the two multi-level H-type stripline feeding networks corresponding to the bridge structure at the intersection are located and the PCB layer where the transmission bridge line 153 is located). The multi-level H-type stripline feeding network in two polarization directions is formed in a staggered layout through the bridge structure, and the interference between different multi-level H-type stripline feeding networks on the same layer and the number of PCB layers are reduced under the premise of ensuring the necessary port isolation.

[0062] like Fig. 9 As shown, the stripline and waveguide transition layer 100c includes a plurality of transition units, and the transition units include a signal transmission stripline 171 and a coupling patch 172 in different interlayers. One end of the signal transmission stripline 171 is connected to the input end / output end of the multi-stage H-type stripline feeding network through an interlayer coupling gap, and the other end is connected to the coupling patch 172 through an H-type microstrip coupling gap 173. The signal is transmitted along the signal transmission stripline 171, coupled to the coupling patch 172 through the H-type microstrip coupling gap 173, and the TM of the coupling patch 172 is excited. 01The mode realizes broadband transition to the rectangular waveguide, thereby realizing the transition from stripline to waveguide. In order to constrain electromagnetic signals, a circle of first grounding holes 174 arranged in a rectangular ring is provided around the coupling patch 172, and the first grounding holes 174 are connected to the ground layer in the stripline and waveguide transition layer 100c.

[0063] like Fig.11 and Fig.12 The simulation results of the stripline and waveguide transition layer 100c in the K band and Ka band are shown respectively, wherein the ordinate represents the reflection coefficient (dB) and the abscissa represents the operating frequency (GHz). Fig.11 It can be seen that the reflection coefficient of line 1108 in the K band is below -15dB. Fig.12 It can be seen that the reflection coefficient of line 1112 in the Ka band is below -19dB.

[0064] Specifically, the multiple switching units include at least one pair of K-band switching units and at least one pair of Ka-band switching units; in the K-band switching unit, the rectangular area 175 surrounded by the first grounding holes 174 serves as a K-band input / output port 181; in the Ka-band switching unit, the rectangular area 175 surrounded by the first grounding holes 174 serves as a Ka-band input / output port 182.

[0065] Specifically, Fig.10 In the example shown, there is a pair of K-band switching units, corresponding to a pair of K-band input / output ports 181; there are two pairs of Ka-band switching units, corresponding to two pairs of Ka-band input / output ports 182. The rectangular waveguide feeds the antenna through these ports. When a pair of K-band input / output ports 181 are fed with equal phase, the K-band antenna generates two orthogonal linear polarization waves; when fed with a +90° or -90° phase difference, the K-band antenna generates left-hand circular polarization or right-hand circular polarization waves. Similarly, when a pair of Ka-band input / output ports 182 are fed with equal phase, the Ka-band antenna generates two orthogonal linear polarization waves; when fed with a +90° or -90° phase difference, the Ka-band antenna generates left-hand circular polarization or right-hand circular polarization waves.

[0066] Preferably, second grounding holes 170 are arrayed on both sides of the signal transmission stripline 171 and on the periphery of the coupling patch 172. The second grounding holes 170 are connected to the stripline and the ground layer in the waveguide transition layer 100c, which can achieve functions such as electromagnetic shielding, interference reduction, impedance matching optimization and signal integrity improvement.

[0067] Specifically, Fig. 9In the example shown, a specific structure of the H-type microstrip coupling slot 173 includes a straight section 173a and an open rectangular ring 173b symmetrically and vertically connected to both ends of the straight section 173a in the length direction, and the opening of the open rectangular ring 173b faces outward and is located on the extension line of the straight section 173a along the length direction; through this structural setting, the bandwidth of the coupling slot can be effectively improved to achieve coupling of broadband signals.

[0068] In the layer height direction of the strip line and the waveguide transition layer 100 c , the projection of the signal transmission strip line 171 intersects perpendicularly with the projection of the straight segment 173 a , so as to realize the feeding of the straight segment 173 a and the open rectangular ring 173 b .

[0069] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application.

Claims

1. A dual-frequency common aperture antenna radiating unit, characterized in that: An antenna layer (100a) is arranged in a periodic array on the antenna, and each radiating unit comprises: A K-band folded oscillator (111) located on the top surface of the antenna layer (100a); Four Ka-band microstrip patches (112) located in the middle interlayer of the antenna layer (100a) and evenly distributed around the K-band folded oscillator (111); and Two groups of feeding baluns (122) arranged in an orthogonal manner and located in the middle layer of the antenna layer (100a), the feeding baluns (122) being connected to the K-band folded oscillator (111) through conductive vias (121); The feeding balun (122) is coupled with a feeding network layer (100b) located below the antenna layer (100a) in the antenna through an H-shaped K-band coupling slot (126); when two groups of feeding baluns (122) are fed with the same phase, K-band dual linear polarization is achieved; and when 90° phase difference feeding is used, K-band left-hand circular polarization or right-hand circular polarization is achieved; Each Ka-band microstrip patch (112) is coupled to a feeding network layer (100b) via two orthogonally arranged H-type Ka-band coupling slots (125); when the two H-type Ka-band coupling slots (125) are fed with the same phase, Ka-band dual linear polarization is achieved; and when 90° phase difference feeding is used, Ka-band left-hand circular polarization or right-hand circular polarization is achieved; The H-type K-band coupling slot (126) and the H-type Ka-band coupling slot (125) are located in an H-type coupling slot array (130) arranged on the bottom surface of the antenna layer (100a) or the top surface of the feed network layer (100b).

2. The dual-frequency common-aperture antenna radiation unit according to claim 1, characterized in that: The K-band folded oscillator (111) is in a cross-shaped ring structure, comprising four ring structures (111a) in a circular array and connected together to form a cross shape.

3. The dual-frequency common-aperture antenna radiation unit according to claim 2, characterized in that: Each group of feeding baluns (122) includes a feeding balun upper structure (122a) and a feeding balun lower structure (122b); one end of the feeding balun upper structure (122a) is a 180° phase feeding line (122c), and the other end is connected to the floor layer (124) in the antenna layer (100a) through a ground via (123); one end of the feeding balun lower structure (122b) is a 0° phase feeding line (122d), and the other end is coupled to the feeding network layer (100b) through an H-type K-band coupling slot (126); The K-band folded oscillator (111) is connected to two 0° phase feed lines (122d) and two 180° phase feed lines (122c) through four conductive vias (121).

4. The dual-frequency common-aperture antenna radiation unit according to claim 2, characterized in that: The K-band folded oscillator (111) corresponds to two independent K-band electromagnetic transmission paths. When used for receiving signals, one of the paths passes through the K-band folded oscillator (111), a group of feeding baluns (122), and an H-type K-band coupling slot (126) in sequence, and the other path passes through the K-band folded oscillator (111), another group of feeding baluns (122), and an H-type K-band coupling slot (126) in sequence. The path used for transmitting signals is opposite to the path used for receiving signals.

5. The dual-frequency common-aperture antenna radiation unit according to claim 2, characterized in that: The length direction of the ring-shaped structure (111a) is arranged at a predetermined angle with the side of the antenna layer (100a), and the Ka-band microstrip patches (112) are respectively located in the length direction of the ring-shaped structure (111a).

6. The dual-frequency common-aperture antenna radiation unit according to claim 1, characterized in that: Each Ka-band microstrip patch (112) comprises an upper microstrip patch unit (112a) and a lower microstrip patch unit (112b) which are arranged at intervals along the layer height direction of the antenna layer (100a).

7. The dual-frequency common-aperture antenna radiation unit according to claim 6, characterized in that: A circle of grounding conductive holes is arrayed on the periphery of the edges of the upper microstrip patch unit (112a) and the lower microstrip patch unit (112b), and the grounding conductive holes are connected to the floor layer (124) in the antenna layer (100a).

8. The dual-frequency common-aperture antenna radiation unit according to claim 6, characterized in that: Each Ka-band microstrip patch (112) corresponds to two independent Ka-band electromagnetic transmission paths. When used to transmit signals, one of the paths passes through one of the H-type Ka-band coupling slots (125), a lower microstrip patch unit (112b), and an upper microstrip patch unit (112a) in sequence, and the other path passes through another H-type Ka-band coupling slot (125), a lower microstrip patch unit (112b), and an upper microstrip patch unit (112a) in sequence. The path used for receiving signals is opposite to the path used for transmitting signals.

9. A dual-frequency common aperture antenna, characterized in that: It comprises an antenna layer (100a), a feed network layer (100b), and a stripline and waveguide transition layer (100c) stacked from top to bottom, wherein the antenna layer (100a) comprises a dual-frequency co-aperture antenna radiation unit as described in any one of claims 1 to 8.

10. The dual-frequency common aperture antenna according to claim 9, characterized in that: The feed network layer (100b) comprises a plurality of mutually isolated multi-stage H-type stripline feed networks, the ends of the multi-stage H-type stripline feed networks having an electrical coupling structure (148) for electrically coupling with an H-type coupling slot array (130) arranged on the bottom surface of the antenna layer (100a) or the top surface of the feed network layer (100b) to conduct signals with the antenna layer (100a), and the input / output interlayer coupling slots of the multi-stage H-type stripline feed network connect the stripline and the waveguide switching layer (100c).

11. The dual-frequency common aperture antenna according to claim 10, characterized in that: The feeding network layer (100b) comprises four mutually isolated multi-stage H-type stripline feeding networks, namely a first H-type feeding network (140), a second H-type feeding network (142), a third H-type feeding network (144), and a fourth H-type feeding network (146); The signal transmission lengths of the first H-type feeding network (140) and the second H-type feeding network (142) are the same, and they are two orthogonal polarization feeding networks in the Ka frequency band; The third H-type feeding network (144) and the fourth H-type feeding network (146) have the same signal transmission length and are two orthogonal polarization feeding networks in the K frequency band.

12. The dual-frequency common aperture antenna according to claim 11, characterized in that: The feed network layer (100b) comprises two PCB layers, the first H-type feed network (140) and the third H-type feed network (144) are located on one of the PCB layers, and the second H-type feed network (142) and the fourth H-type feed network (146) are located on the other PCB layer; A bridge structure is used at the intersection of transmission branches of different multi-level H-type stripline feeding networks in the same PCB layer, and a transmission branch line (151) of one of the multi-level H-type stripline feeding networks at the intersection is disconnected, and vertical conductive vias (152) are respectively provided at two ends of the disconnection, and the two vertical conductive vias (152) are connected to the same transmission bridge line (153) located in another PCB layer.

13. The dual-frequency common aperture antenna according to claim 11, characterized in that: The stripline and waveguide switching layer (100c) comprises a plurality of switching units, wherein the switching units comprise signal transmission striplines (171) and coupling patches (172) located in different interlayers, wherein one end of the signal transmission stripline (171) is connected and conducted with the input end / output end of a multi-stage H-type stripline feeding network via an interlayer coupling gap, and the other end is connected and conducted with the coupling patch (172) via an H-type microstrip coupling gap (173).

14. The dual-frequency common aperture antenna according to claim 13, characterized in that: The multiple switching units include at least one pair of K-band switching units and at least one pair of Ka-band switching units; A circle of first grounding holes (174) arranged in a rectangular ring is provided on the circumference of the coupling patch (172), and the first grounding holes (174) are connected to the ground layer in the strip line and waveguide transition layer (100c); In the K-band switching unit, a rectangular area (175) surrounded by the first grounding hole (174) serves as a K-band input / output port (181); In the Ka-band switching unit, a rectangular area (175) surrounded by the first grounding hole (174) serves as a Ka-band input / output port (182).

15. The dual-frequency common aperture antenna according to claim 14, characterized in that: Second grounding holes (170) are respectively arranged in arrays on both sides of the signal transmission stripline (171) and on the periphery of the coupling patch (172); the second grounding holes (170) are connected to the ground layer in the stripline and waveguide switching layer (100c).

16. The dual-frequency common aperture antenna according to claim 13, characterized in that: The H-shaped microstrip coupling gap (173) comprises a straight section (173a) and an open rectangular ring (173b) symmetrically and vertically connected to both ends of the straight section (173a) in the length direction, wherein the opening of the open rectangular ring (173b) faces outward and is located on an extension line of the straight section (173a) in the length direction; In the layer height direction of the stripline and waveguide transition layer (100c), the projection of the signal transmission stripline (171) and the projection of the straight segment (173a) intersect vertically.

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