A phased array antenna subarray

Abstract

This invention relates to a phased array antenna subarray, comprising an external interface layer, a beamforming network layer, an amplitude and phase multifunction layer, a low-noise amplifier (LNOA) layer, and an antenna layer. The antenna layer and the LNOA layer are disposed on a first metal-based PCB board, while the amplitude and phase multifunction layer, the LNOA layer, and the antenna layer are disposed on a second metal-based PCB board. The bottom layer of the first metal-based PCB board and the top layer of the second metal-based PCB board are connected together, achieving integrated encapsulation of the external interface layer, beamforming network layer, amplitude and phase multifunction layer, LNOA layer, and antenna layer. Both the first and second metal-based PCB boards are provided with multiple grounding and heat-conducting vias. This invention enables the phased array antenna to be lightweight, small, and thin while also possessing excellent heat dissipation and good scalability, allowing for expansion of the number of elements and frequency bands.

Description

Technical Field

[0001] This invention belongs to the field of satellite antenna technology and relates to a phased array antenna subarray. Background Technology

[0002] This project originates from the National Major Special Project Low-Earth Orbit Satellite Internet System (a new type of network capable of providing broadband internet access and other communication services to ground and air terminals, characterized by wide coverage, low latency, broadband speed, and low cost). The Ka-band multi-beam active phased array antenna is a crucial subsystem of the satellite broadband communication payload, enabling broadband communication. It can generate multiple spot beams in real time, each capable of scanning to cover all positions within the sub-satellite range and rapidly switching between different positions, thus meeting the requirements for wide broadband coverage and flexible access.

[0003] Due to the high operating frequency and small spacing between antenna elements, current traditional Ka-band multi-beam phased array antennas employ a brick-like architecture, which is disadvantageous in terms of size, weight, and integration, making it difficult to meet the new requirements of low-Earth orbit satellite internet systems for antennas (low profile, small size, lightweight, and high integration). The main challenges are the high-power heat dissipation resulting from high-density integration and the need for low profile and miniaturization. These two issues have always been contradictory in the implementation of phased array antennas, making it difficult to achieve a good balance. There are two traditional implementation solutions: one is the brick-like architecture, which can solve the high-power heat dissipation problem to some extent, but requires some compromise in terms of low profile and miniaturization; the other is the tile-like architecture, which performs better in terms of low profile and miniaturization, but cannot effectively solve the high-power heat dissipation problem under high integration.

[0004] In addition, most existing phased array antennas with a watt-shaped architecture adopt a packaged antenna structure, that is, the antenna layer and the network layer are integrated on a PCB board, with the antenna layer on the top layer of the PCB board and the TR components mounted on the bottom layer of the PCB board. This form has the following problems: First, the path from the antenna to the LNA or PA is long and the insertion loss is large, which will result in a larger overall noise figure or reduced efficiency of the antenna; Second, as the frequency increases, the layout density increases, which brings greater challenges to heat dissipation; Third, the phased array antenna subarray adopts secondary packaging, which is relatively complex in process implementation and has low mass production efficiency. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a phased array antenna subarray that can make the phased array antenna light, small and thin while having a better heat dissipation effect. The invented antenna subarray has the characteristics of low profile and high density integration and has good scalability.

[0006] The solution of the present invention is: a phased array antenna subarray, comprising an external interface layer, a beamforming network layer, an amplitude and phase multifunctional layer, a low-noise amplifier and power amplifier layer, and an antenna layer;

[0007] The antenna layer and the low-noise amplifier / power amplifier layer are disposed on the first metal-based PCB board, and the antenna layer and the low-noise amplifier / power amplifier layer are electrically connected; the amplitude and phase multifunction layer, the beamforming network layer and the external interface layer are disposed on the second metal-based PCB board, the bottom layer of the first metal-based PCB board and the top layer of the second metal-based PCB board are connected together, the antenna layer and the low-noise amplifier / power amplifier layer are electrically connected, the low-noise amplifier / power amplifier layer and the amplitude and phase multifunction layer are electrically connected, the amplitude and phase multifunction layer and the beamforming network layer are electrically connected, and the beamforming network layer and the external interface layer are electrically connected.

[0008] Furthermore, the antenna layer includes N metal patch antenna elements, which are arranged on the top layer of the first metal base PCB board, where N≥1; the bottom layer of the first metal base PCB board has N stepped cavities.

[0009] The low-noise amplifier layer includes N low-noise amplifier MMIC chips and N first heat sink carriers. In each stepped cavity, the low-noise amplifier MMIC chips are soldered onto the first heat sink carriers, and the first heat sink carriers are attached to the first metal base of the first metal base PCB board.

[0010] The low-noise amplifier MMIC chip corresponds one-to-one with the metal patch antenna unit in the antenna layer, and the two are electrically connected through the first RF feed line; the low-noise amplifier MMIC chip is electrically connected to the amplitude and phase multifunction layer through the second RF feed line.

[0011] Furthermore, the stepped cavity where the low-noise amplifier MMIC chip is located is provided with a first metal cover plate for the encapsulation protection and electromagnetic shielding of the low-noise amplifier MMIC chip.

[0012] Furthermore, the top layer of the second metal-based PCB board has M stepped cavities, where M ≥ 1;

[0013] The amplitude-phase multifunctional layer includes M amplitude-phase multifunctional MMIC chips and M second heat sink carriers. In each stepped cavity, the amplitude-phase multifunctional MMIC chips are soldered onto the second heat sink carriers, and the second heat sink carriers are attached to the second metal base of the second metal base PCB board.

[0014] The amplitude-phase multi-functional MMIC chip is electrically connected to the low-noise amplifier and power amplifier layer through the third RF feed line. The third RF feed line is connected to the second RF feed line to form an electrical signal path.

[0015] The amplitude-phase multi-functional MMIC chip is electrically connected to the beamforming network layer via the fourth RF feed line.

[0016] Furthermore, the number of low-noise amplifier MMIC chips that can be connected to one multi-functional MMIC chip is 1 to 8, where M≤N≤8M.

[0017] Furthermore, the stepped cavity where the amplitude-phase multifunctional MMIC chip is located is provided with a second metal cover plate for the encapsulation protection and electromagnetic shielding of the amplitude-phase multifunctional MMIC chip.

[0018] Furthermore, the beamforming network layer is disposed in the middle signal layer of the second metal-based PCB board and includes multiple power dividers, which are implemented by striplines and embedded resistors; when the traces between the power dividers intersect, they are implemented by setting the traces in different stacks inside the second metal-based PCB board.

[0019] Furthermore, the external interface layer is located on the bottom layer of the second metal-based PCB board.

[0020] The external interface layer includes an RF connector and a low-frequency connector; the beamforming network layer is electrically connected to the RF connector via the fifth RF feed line, and the beamforming network layer is electrically connected to the low-frequency connector via the low-frequency power supply control line.

[0021] Furthermore, BGA balls are soldered between the bottom layer of the first metal-based PCB and the top layer of the second metal-based PCB to achieve electrical connection and grounding;

[0022] A heat dissipation metal block is welded between the bottom layer of the first metal-based PCB board and the top layer of the second metal-based PCB board for heat dissipation of the phased array antenna subarray.

[0023] Furthermore, the first metal-based PCB board is provided with multiple first grounding thermal conductive vias, and the second metal-based PCB board is provided with multiple second grounding thermal conductive vias; the positions of the first grounding thermal conductive vias and the second grounding thermal conductive vias are required to avoid all RF feed lines and low-frequency power supply control lines.

[0024] The advantages of this invention compared to the prior art are:

[0025] (1) The present invention adopts POP (Package on Package) system-level stacked advanced packaging, and integrates antenna, RF active channel and network into ultra-high density. The interconnection between the components eliminates the need for traditional connectors. Based on metal-based multilayer PCB technology, it ensures that the path from the antenna layer to the low noise amplifier / power amplifier layer is extremely short and the loss is minimal, which greatly improves the electrical performance indicators such as noise figure and efficiency of the phased array antenna.

[0026] (2) The present invention directly encapsulates the MMIC chip inside the PCB board, eliminating the need for secondary encapsulation, simplifying the complexity of antenna integration, enabling one-time encapsulation of active antenna board, thereby greatly reducing the weight and height of the antenna, simplifying the subsequent processes of antenna production, eliminating debugging, reducing testing procedures and steps, achieving high yield, significantly reducing costs and greatly improving mass production efficiency.

[0027] (3) The present invention effectively solves the problem of high-power heat dissipation caused by high-density integration by using the metal base and metallized vias inside the PCB multilayer board, the BGA solder balls and metal blocks that interconnect the two metal base PCB boards.

[0028] (4) The present invention has good scalability. It can not only expand the number of units, but also expand the frequency band, and has good universality. Attached Figure Description

[0029] Figure 1 This is a schematic diagram illustrating the principle of a phased array antenna subarray according to an embodiment of the present invention;

[0030] Figure 2 This is a structural view of a phased array antenna subarray according to an embodiment of the present invention. Detailed Implementation

[0031] The invention will now be further described with reference to the accompanying drawings.

[0032] Figure 1 This is a schematic diagram of the phased array antenna subarray of the present invention. The antenna subarray can be used as a receiving subarray or a transmitting subarray. It includes an external interface layer, a beamforming network layer 14, an amplitude and phase multifunction layer, a low-noise amplifier / power amplifier layer, and an antenna layer.

[0033] For the transmitting subarray, the signal flow is sequentially: external interface layer, beamforming network layer 14, amplitude and phase multifunction layer, power amplifier layer, and antenna layer; for the receiving subarray, the signal flow is sequentially: antenna layer, low noise amplifier and power amplifier layer, amplitude and phase multifunction layer, beamforming network layer 14, and external interface layer.

[0034] The system comprises the following layers: External interface layer, which connects the phased array antenna subarray to external devices for RF power supply and low-frequency power control signals; Beamforming network layer 14, which distributes power for transmitted RF signals and synthesizes power for received RF signals, and integrates low-frequency power control signals; Amplitude and phase multifunction layer, which controls the phase shifting, attenuation, amplification, and switching of RF signals; Low-noise amplifier / power amplifier layer, which amplifies RF signals with low noise during reception and amplifies RF signals with power during transmission; and Antenna layer, which converts guided waves propagating in the circuit into spatial electromagnetic wave signals during transmission and converts spatial electromagnetic wave signals back into guided waves propagating in the circuit during reception.

[0035] In this embodiment of the invention, the antenna layer and the low-noise amplifier / power amplifier layer are disposed on a first metal-based PCB board 2, and the bottom layer of the first metal-based PCB board 2 has N stepped cavities. The amplitude-phase multifunctional layer, the beamforming network layer 14, and the external interface layer are disposed on a second metal-based PCB board 10, and the top layer of the second metal-based PCB board 10 has M stepped cavities. The number of N is 1 to 8 times M. The bottom layer of the first metal-based PCB board 2 and the top layer of the second metal-based PCB board 10 are connected together to realize the overall encapsulation of the antenna layer, the low-noise amplifier / power amplifier layer, the amplitude-phase multifunctional layer, the low-noise amplifier / power amplifier layer, and the antenna layer.

[0036] Specifically, the antenna layer includes N metal patch antenna units 1, which are arranged on the top layer of the first metal base PCB board 2, where N≥1.

[0037] The low-noise amplifier layer is disposed on the bottom layer of the first metal-based PCB board 2. The low-noise amplifier layer includes N low-noise amplifier MMIC chips 3 and N first heat sinks 4, with one low-noise amplifier MMIC chip 3 corresponding to one first heat sink 4. In each stepped cavity, the low-noise amplifier MMIC chip 3 is soldered onto the first heat sink 4, and the first heat sink 4 is attached to the first metal base 7 of the first metal-based PCB board 2.

[0038] The low-noise amplifier MMIC chip 3 corresponds one-to-one with the metal patch antenna element 1 in the antenna layer, and the two are electrically connected through the first RF feed line 19. The low-noise amplifier MMIC chip 3 is electrically connected to the amplitude and phase multifunction layer through the second RF feed line 20.

[0039] In this embodiment, a first bonding wire 6 is connected between the low-noise amplifier MMIC chip 3 and the first RF feed line 19, and between the low-noise amplifier MMIC chip 3 and the second RF feed line 20. The first bonding wire 6 is used to realize the electrical connection between the low-noise amplifier MMIC chip 3 and the first RF feed line 19, and the electrical connection between the low-noise amplifier MMIC chip 3 and the second RF feed line 20.

[0040] A first metal cover plate 5 is placed above the stepped cavity where the low-noise amplifier MMIC chip 3 is located, so as to realize the encapsulation protection and electromagnetic shielding of the low-noise amplifier MMIC chip 3.

[0041] BGA balls 8 and heat dissipation metal blocks 9 are soldered between the bottom layer of the first metal-based PCB board 2 and the top layer of the second metal-based PCB board 10. The soldering positions of the BGA balls 8 and heat dissipation metal blocks 9 are selected on the pads outside the stepped cavities of the two metal-based PCB boards. The first metal-based PCB board 2 and the second metal-based PCB board 10 are interconnected through the BGA balls 8 and heat dissipation metal blocks 9, making the external interface layer, beamforming network layer 14, amplitude and phase multifunction layer, low noise amplifier and power amplifier layer and antenna layer a whole. Among them, the BGA balls 8 are mainly used to realize the electrical connection and grounding of the two metal-based PCB boards, and the heat dissipation metal blocks 9 are used for heat dissipation of the antenna subarray. The amplitude and phase multifunction layer is set on the top layer of the second metal-based PCB board 10. The amplitude and phase multifunction layer includes M amplitude and phase multifunction MMIC chips 11 and M second heat sink carriers 12. In each stepped cavity, the amplitude and phase multifunction MMIC chips 11 are soldered to the second heat sink carriers 12, and the second heat sink carriers 12 are attached to the second metal base 15 of the second metal-based PCB board 10.

[0042] The amplitude-phase multi-function MMIC chip 11 is electrically connected to the low-noise amplifier / power amplifier layer via a third RF feed line 21. The third RF feed line 21 is correspondingly connected to the second RF feed line 20, forming a path for electrical signals. Moreover, one amplitude-phase multi-function MMIC chip 11 can connect to 1 to 8 low-noise amplifier / power amplifier MMIC chips 3. The amplitude-phase multi-function MMIC chip 11 is electrically connected to the beamforming network layer 14 via a fourth RF feed line 22.

[0043] Preferably, the second RF feed line 20 is connected to the pad of the BGA ball 8 on the first metal base PCB board 2, and the third RF feed line 21 is connected to the pad of the BGA ball 8 on the second metal base PCB board 10. The third RF feed line 21 is connected to the second RF feed line 20 by soldering the BGA ball 8 between the two metal base PCB boards.

[0044] In this embodiment, a second bonding wire 26 is connected between the amplitude-phase multi-functional MMIC chip 11 and the third RF feed line 21, and between the amplitude-phase multi-functional MMIC chip 11 and the fourth RF feed line 22. The second bonding wire 26 realizes the electrical connection between the amplitude-phase multi-functional MMIC chip 11 and the third RF feed line 21, and the electrical connection between the amplitude-phase multi-functional MMIC chip 11 and the fourth RF feed line 22.

[0045] A second metal cover plate 13 is placed above the stepped cavity where the amplitude-phase multifunctional MMIC chip 11 is located, so as to realize the encapsulation protection and electromagnetic shielding of the amplitude-phase multifunctional MMIC chip 11.

[0046] The beamforming network layer 14 is disposed in the middle signal layer of the second metal base PCB board 10 and includes multiple power dividers, which are implemented by striplines and embedded resistors; when the traces between the power dividers cross, they are implemented by setting the traces in different stacks inside the second metal base PCB board 10.

[0047] The external interface layer is located on the bottom layer of the second metal-based PCB board 10. The external interface layer includes an RF connector 16, a low-frequency connector 17, and a mounting mechanism post 18. The beamforming network layer 14 is electrically connected to the RF connector 16 via the fifth RF feed line 23, and is electrically connected to the low-frequency connector 17 via the low-frequency power supply control line. The phased array antenna subarray is fixedly mounted on the external device via the mounting mechanism post 18.

[0048] In this invention, the first metal-based PCB board 2 is provided with a plurality of first grounding thermal conductive vias 24, and the second metal-based PCB board 10 is provided with a plurality of second grounding thermal conductive vias 25. The positions of the first grounding thermal conductive vias 24 and the second grounding thermal conductive vias 25 are required to avoid all radio frequency feed lines and low-frequency power supply control lines.

[0049] The overall architecture of the antenna subarray described above belongs to the advanced packaging technology of POP (Package on Package). The upper and lower parts of the BGA ball 8 and the heat sink metal block 9 can be regarded as the first package and the second package, respectively. The two packages are stacked at the system level by welding the BGA ball 8 and the heat sink metal block 9.

[0050] The heat dissipation path of the phased array antenna subarray is as follows: the low-noise amplifier MMIC chip 3 inside the first metal base PCB board 2 is soldered onto the first heat sink 4, and the first heat sink 4 is attached to the first metal base 7. The heat generated by the low-noise amplifier MMIC chip 3 is first conducted to the first heat sink 4, and then from the first heat sink 4 to the first metal base 7, realizing the distribution of point heat source to surface heat source. The heat on the first metal base 7 is then conducted through a large number of first grounding heat conduction holes 24 to the BGA ball 8 and heat sink metal block 9 between the first metal base PCB board 2 and the second metal base PCB board 10. The heat continues to be conducted through the BGA ball 8 and heat sink metal block 9. The heat dissipates to the second metal-based PCB board 10 below. The phase-amplitude multi-functional MMIC chip 11 inside the second metal-based PCB board 10 is soldered onto the second heat sink carrier 12, which is then bonded to the second metal base 15. The heat generated by the phase-amplitude multi-functional MMIC chip 11 is first conducted to the second heat sink carrier 12, and then from the second heat sink carrier 12 to the second metal base 15, achieving a distribution from a point heat source to a surface heat source. The heat on the second metal base 15 is then conducted to the mounting and fixing heat sink plate of the antenna subarray through numerous second grounding heat-conducting through-holes 25. The mounting and fixing heat sink plate is a structural component integrated into the antenna subarray, serving as a heat dissipation support. The entire heat dissipation path fully utilizes the advantages of short vertical distance and good heat uniformity of the metal base within the multi-layer PCB board, achieving highly efficient heat dissipation with excellent results.

[0051] The above description is provided to those skilled in the art regarding the invention and its embodiments. This description should be considered illustrative rather than limiting. Those skilled in the art can implement specific operations based on the ideas in the claims, for example... Figure 2 The structure of the phased array antenna, including the number of antenna elements and channels, is shown merely to better illustrate this antenna structure and is not limiting. Various changes in form and detail may be made without departing from the spirit and scope of the invention as defined in the appended claims. All of these should be considered within the scope of this invention.

[0052] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A phased array antenna subarray, characterized in that, It includes an external interface layer, a beamforming network layer (14), an amplitude-phase multifunctional layer, a low-noise amplifier and power amplifier layer, and an antenna layer; The antenna layer and the low-noise amplifier and power amplifier layer are arranged on the first metal-based PCB board (2), and the antenna layer is electrically connected to the low-noise amplifier and power amplifier layer; the amplitude-phase multifunctional layer, the beamforming network layer (14), and the external interface layer are arranged on the second metal-based PCB board (10). The bottom layer of the first metal-based PCB board (2) is connected to the top layer of the second metal-based PCB board (10). The low-noise amplifier and power amplifier layer is electrically connected to the amplitude-phase multifunctional layer, the amplitude-phase multifunctional layer is electrically connected to the beamforming network layer (14), and the beamforming network layer (14) is electrically connected to the external interface layer; The antenna layer includes N metal patch antenna units (1), and the metal patch antenna units (1) are arranged on the top layer of the first metal-based PCB board (2), where N≥1; the bottom layer of the first metal-based PCB board (2) has N stepped cavities; The low-noise amplifier and power amplifier layer includes N low-noise amplifier and power amplifier MMIC chips (3) and N first heat sink carriers (4). In each stepped cavity, the low-noise amplifier and power amplifier MMIC chip (3) is welded to the first heat sink carrier (4), and the first heat sink carrier (4) is pasted on the first metal base (7) of the first metal-based PCB board (2); The low-noise amplifier and power amplifier MMIC chips (3) correspond to the metal patch antenna units (1) in the antenna layer one by one, and the two are electrically connected through the first RF feeder line (19); the low-noise amplifier and power amplifier MMIC chips (3) are electrically connected to the amplitude-phase multifunctional layer through the second RF feeder line (20); The top layer of the second metal-based PCB board (10) has M stepped cavities, where M≥1; The amplitude-phase multifunctional layer includes M amplitude-phase multifunctional MMIC chips (11) and M second heat sink carriers (12). In each stepped cavity, the amplitude-phase multifunctional MMIC chip (11) is welded to the second heat sink carrier (12), and the second heat sink carrier (12) is pasted on the second metal base (15) of the second metal-based PCB board (10); The amplitude-phase multifunctional MMIC chips (11) are electrically connected to the low-noise amplifier and power amplifier layer through the third RF feeder line (21), and the third RF feeder line (21) corresponds to and communicates with the second RF feeder line (20) to form a path for electrical signals; The amplitude-phase multifunctional MMIC chips (11) are electrically connected to the beamforming network layer (14) through the fourth RF feeder line (22); BGA balls (8) are welded between the bottom layer of the first metal-based PCB board (2) and the top layer of the second metal-based PCB board (10) for electrical connection and grounding; A heat dissipation metal block (9) is also welded between the bottom layer of the first metal-based PCB board (2) and the top layer of the second metal-based PCB board (10) for heat dissipation of the phased array antenna subarray; The first metal-based PCB board (2) is provided with a plurality of first grounding and heat conduction through holes (24), and the second metal-based PCB board (10) is provided with a plurality of second grounding and heat conduction through holes (25); the arrangement positions of the first grounding and heat conduction through holes (24) and the second grounding and heat conduction through holes (25) are required to avoid all RF feeder lines and low-frequency power supply control lines; The heat dissipation path flow direction of the phased array antenna subarray is as follows: the heat generated by the low-noise amplifier power amplifier MMIC chip (3) is first exported to the first heat sink carrier (4), and then exported from the first heat sink carrier (4) to the first metal base (7), realizing the distribution of point heat sources to surface heat sources; the heat on the first metal base (7) is then exported to the BGA balls (8) and heat dissipation metal blocks (9) between the first metal base PCB board (2) and the second metal base PCB board (10) through a large number of first grounding heat conduction vias (24), and the heat continues to be exported to the second metal base PCB board (10) below through the BGA balls (8) and heat dissipation metal blocks (9); the heat generated by the amplitude-phase multifunctional MMIC chip (11) is first exported to the second heat sink carrier (12), and then exported from the second heat sink carrier (12) to the second metal base (15), realizing the distribution of point heat sources to surface heat sources, and the heat on the second metal base (15) is then exported to the installation and fixing heat dissipation board of the antenna subarray through a large number of second grounding heat conduction vias (25). The installation and fixing heat dissipation board is a structural component integrated in the antenna subarray and plays a role in heat dissipation and support.

2. The phased array antenna subarray according to claim 1, wherein The step cavity where the low-noise amplifier power amplifier MMIC chip (3) is located is provided with a first metal cover plate (5) for the packaging protection and electromagnetic shielding of the low-noise amplifier power amplifier MMIC chip (3).

3. The phased array antenna subarray according to claim 1, characterized in that, The number of low-noise amplifier power amplifier MMIC chips (3) that an amplitude-phase multifunctional MMIC chip (11) can connect is 1 to 8, and M ≤ N ≤ 8M.

4. The phased array antenna subarray according to claim 1, characterized in that, The step cavity where the amplitude-phase multifunctional MMIC chip (11) is located is provided with a second metal cover plate (13) for the packaging protection and electromagnetic shielding of the amplitude-phase multifunctional MMIC chip (11).

5. The phased array antenna subarray according to claim 3, characterized in that, The beamforming network layer (14) is arranged on the intermediate signal layer of the second metal base PCB board (10) and includes a plurality of power dividers, and the power dividers are realized in the form of strip lines and buried resistors; when the traces between the power dividers cross, the traces are arranged in different laminations inside the second metal base PCB board (10).

6. The phased array antenna subarray according to claim 5, wherein The external interface layer is arranged on the bottom layer of the second metal base PCB board (10). The external interface layer includes a radio frequency connector (16) and a low-frequency connector (17); the beamforming network layer (14) is electrically connected to the radio frequency connector (16) through a fifth radio frequency feeder line (23), and the beamforming network layer (14) is electrically connected to the low-frequency connector (17) through a low-frequency power supply control line.

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