Phased array system suitable for air coverage

Abstract

The invention belongs to the field of communication and array antennas, and discloses a phased array system suitable for air coverage, which comprises a power division network and a plurality of TR components connected with one end of the power division network, one end, far away from the power division network, of each TR assembly is sequentially connected with a pitching beam forming network BFN and a plurality of antenna arrays ANT; the pitching beamforming network BFN is used for generating wide beams in the pitching direction through the plurality of antenna arrays ANT in a fixed beamforming mode, wherein the gains of the wide beams are sequentially reduced in the directions from a far field, a middle field to a near field. Compared with the prior art, an original multi-dimensional phased array can be simplified into a one-dimensional phased array, scanning in the horizontal direction only needs to be supported, under the condition that the array scale is not changed, the number of parts such as TR assemblies and phase shifter PS parts can be greatly reduced, and then the design cost of a phased array system is effectively reduced. Meanwhile, a wide wave beam with the gain sequentially reduced in the directions from the far field to the near field is generated in the pitching direction in a fixed wave beam forming mode, non-blind area coverage of the middle field area and the near field area is achieved while the gain of the far field area is considered, and the complexity of network access searching and tracking during air communication is also reduced.

Description

Technical Field

[0001] The invention belongs to the field of communication and array antennas, and relates to a phased array system suitable for air coverage. Background Art

[0002] In ground-to-air communications, airborne equipment is usually at a high altitude and can cover a long distance, so ground equipment is required to achieve long-distance communication. At the same time, airborne equipment may appear at any position in the air, so ground equipment is required to achieve coverage at all pitch angles in the entire air range. In this communication scenario, ground equipment is required to have both high gain and coverage without blind spots in the air, while taking into account the needs of communication in motion and rapid movement in the air. Therefore, the use of two-dimensional array antennas has become a commonly used communication technology in ground-to-air communications.

[0003] Commonly used array antennas include digital array antennas, analog array antennas, and digital-analog hybrid array antennas. In order to achieve scanning in both the elevation and horizontal directions, these three array antennas require the use of more vibration sources, TR components, and phase shifter PS components in the front end to achieve scanning in both the elevation and horizontal dimensions.

[0004] Taking analog array antennas as an example, in order to meet the long-distance communication requirements of far-field communication, the antenna gain and the equivalent isotropic radiated power of the equipment are required to be high. Conventional array antenna designs require a large number of channels, which leads to a sharp increase in costs. Therefore, it is necessary to study an array antenna that combines performance and cost in ground-to-air communications. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art and provide a phased array system suitable for air coverage.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a phased array system suitable for air coverage, comprising a power division network and a plurality of TR components connected to one end of the power division network; an end of each TR component away from the power division network is sequentially connected to an elevation beamforming network BFN ​​and a plurality of antenna arrays ANT; the elevation beamforming network BFN ​​is used to generate a wide beam in an elevation direction through a plurality of antenna arrays ANT in a fixed beamforming manner, the gain of which decreases sequentially along the directions of far field, mid-field to near field.

[0007] Optionally, the power division network includes a plurality of two-power dividers PD; the plurality of two-power dividers PD are connected layer by layer, and the number of output ends of the two-power dividers PD in the last layer is equal to the number of TR components, and are connected to the TR components one by one.

[0008] Optionally, the TR component includes an adjustable attenuator ATT, a phase shifter PS, a first transceiver control switch SW1, a transmitting link power amplifier PA, a receiving link low noise amplifier LNA and a second transceiver control switch SW2; one end of the adjustable attenuator ATT is connected to the power division network, and the other end is connected to the adjustable attenuator ATT, the phase shifter PS and the first end of the first transceiver control switch SW1 in sequence; the first end of the second transceiver control switch SW2 is connected to the pitch beamforming network BFN; the second end of the first transceiver control switch SW1 and the second end of the second transceiver control switch SW2 are respectively connected to the two ends of the transmitting link power amplifier PA, and the third end of the first transceiver control switch SW1 and the third end of the second transceiver control switch SW2 are respectively connected to the two ends of the receiving link low noise amplifier LNA.

[0009] Optionally, the elevation beamforming network BFN ​​includes an internal power division network and several propagation delay components; one end of the internal power division network is connected to the TR component, and the other end is connected to one end of the several propagation delay components, and the other ends of the several propagation delay components are respectively connected to several antenna arrays ANT.

[0010] Optionally, the internal power division network includes a plurality of two-power dividers PD; the plurality of two-power dividers PD are connected layer by layer, and the number of output ends of the last layer of two-power dividers PD is equal to the number of propagation delay components, and are connected to the plurality of propagation delay components one by one.

[0011] Optionally, the propagation delay component is a microstrip line.

[0012] Optionally, the delays of the several propagation delay components are obtained in the following manner: based on the system link budget requirements, obtaining the transmitting antenna gain requirements and the receiving antenna gain requirements at each elevation angle; based on the transmitting antenna gain requirements and the receiving antenna gain requirements at each elevation angle, obtaining the optimal phase value at each elevation angle; based on the optimal phase value at each elevation angle, obtaining the delay at each elevation angle.

[0013] Optionally, obtaining the transmitting antenna gain requirement and the receiving antenna gain requirement at each elevation angle according to the system link budget requirement includes: obtaining the transmitting antenna gain requirement at each elevation angle by the following formula: Gtx=L+M-(P+Grx-Sen) Where Gtx is the transmit antenna gain requirement, L is the link loss, M is the link margin, P is the transmit power, Sen is the receiver sensitivity of the other end, and Grx is the receive antenna gain of the other end; The receiving antenna gain requirement at each elevation angle is obtained by the following formula: Grx1=L+M-(P1+Gtx1-Sen1) Among them, Grx1 is the receiving antenna gain requirement, P1 is the peer transmit power, Sen1 is the receiver sensitivity, and Gtx1 is the peer transmit antenna gain.

[0014] Optionally, obtaining the optimal phase value at each pitch angle according to the transmitting antenna gain requirement at each pitch angle includes: generating a target radiation pattern according to the transmitting antenna gain requirement at each pitch angle; taking minimizing the error between the radiation pattern generated based on the optimal phase and the target radiation pattern as the optimization goal and using a curve fitting algorithm to search for the optimal phase to obtain a radiation pattern generated based on the optimal phase; and obtaining the optimal phase value at each pitch angle according to the radiation pattern generated based on the optimal phase.

[0015] Optionally, obtaining the delay at each pitch angle according to the optimal phase value at each pitch angle includes: obtaining the delay at each pitch angle by the following formula:

[0016] in, For delay, is the optimal phase value, c is the speed of light, and f is the working RF frequency.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention is applicable to a phased array system for air coverage. By setting an elevation beamforming network BFN ​​and a plurality of antenna arrays ANT at one end of each TR component away from a power division network, and adopting a fixed beamforming method based on the elevation beamforming network BFN, a wide beam whose gain decreases in the direction of far field, midfield to near field is generated in the elevation direction by a plurality of antenna arrays ANT. The original multi-dimensional phased array can be simplified to one dimension, and only horizontal scanning is required. Without changing the array scale, the number of components such as TR components and phase shifter PS components can be greatly reduced, thereby effectively reducing the design cost of the phased array system. At the same time, a fixed beamforming method is adopted to generate a wide beam whose gain decreases in the direction of far field, midfield to near field in the elevation direction. While taking into account the gain of the far field area, blind-free coverage of the midfield area and the near field area is achieved, and the complexity of network access search and tracking during air communication is also reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the far field, mid field and near field areas during air communication according to an embodiment of the present invention.

[0019] Figure 2 FIG. 4 is a schematic structural diagram of a conventional two-dimensional phased array system according to an embodiment of the present invention.

[0020] Figure 3 Schematic diagram of the structure of a two-dimensional phased array system according to an embodiment of the present invention.

[0021] Figure 4 FIG. 4 is a schematic diagram of the structure of a pitch beamforming network (BFN) according to an embodiment of the present invention.

[0022] Figure 5 It is a combined schematic diagram of a target directional pattern, a transmission directional pattern with a pitch angle of 0, and a directional pattern generated based on an optimal phase according to an embodiment of the present invention.

[0023] Figure 6 It is a schematic diagram of the pitch beam direction output by the phased array system according to an embodiment of the present invention.

[0024] Among them: PD is a power divider, ATT is an adjustable attenuator, PS is a phase shifter, SW1 is the first transceiver control switch, SW2 is the second transceiver control switch, PA is the transmit link power amplifier, LNA is the receive link low noise amplifier, ANT is the antenna array, and BFN is the pitch beamforming network. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings: In one embodiment of the present invention, a phased array system suitable for air coverage is provided, including a power division network and a plurality of TR components connected to one end of the power division network; the end of each TR component away from the power division network is sequentially connected to an elevation beamforming network BFN ​​and a plurality of antenna arrays ANT; the elevation beamforming network BFN ​​is used to generate a wide beam in the elevation direction through the plurality of antenna arrays ANT in a fixed beamforming manner, the gain of which decreases sequentially along the directions of far field, mid-field to near field.

[0028] For details, see Figure 1 Considering the characteristics of air-to-air communication, the pitch direction can be divided into three areas: near field, mid-field and far field. The near-field and mid-field communication distances are relatively short, the elevation angles are high, and the requirements for antenna gain are relatively low. The far-field communication distances are relatively long, the elevation angles are relatively low, and the requirements for antenna gain are relatively high. Here, we consider using a beamforming network in the pitch direction to generate a wide beam model that takes into account both the far, mid and near fields. This wide beam uses fixed beamforming in the pitch direction. The fixed beam gain produces high gain in the far field direction, medium gain in the mid-field direction, and small gain in the near field direction.

[0029] The present invention is applicable to a phased array system for air coverage. By setting an elevation beamforming network BFN ​​and a plurality of antenna arrays ANT at one end of each TR component away from a power division network, and adopting a fixed beamforming method based on the elevation beamforming network BFN, a wide beam whose gain decreases in the direction of far field, midfield to near field is generated in the elevation direction by a plurality of antenna arrays ANT. The original multi-dimensional phased array can be simplified to one dimension, and only horizontal scanning is required. Without changing the array scale, the number of components such as TR components and phase shifters PS can be greatly reduced, thereby effectively reducing the design cost of the phased array system. At the same time, a fixed beamforming method is adopted to generate a wide beam whose gain decreases in the direction of far field, midfield to near field in the elevation direction. While taking into account the gain of the far field area, blind-free coverage of the midfield area and the near field area is achieved, and the complexity of network access search and tracking during air communication is also reduced.

[0030] See also Figure 2 , is a phased array system with a traditional two-dimensional array structure of 4 rows and 4 columns. Figure 2 It can be seen that, corresponding to the number of antenna elements, the phased array system equipment requires 4×4=16 active channels and TR components, so the corresponding number of adjustable attenuators ATT, phase shifters PS, transmitting link power amplifiers PA and receiving link low noise amplifiers LNA should also be 16.

[0031] See also Figure 3 , which corresponds to the present invention Figure 2 A phased array system of the existing phased array system structure, and Figure 2In comparison, an elevation beamforming network BFN ​​is added to the circuit structure of the phased array system of the present invention. The input end of the elevation beamforming network BFN ​​is connected to a TR component, and the output end is connected to four antenna elements ANT. By designing the phase connected to the antenna element ANT, a fixed wide beamforming in the elevation direction is achieved. In this way, the original 16 TR components can be reduced to 4, reducing the design complexity and saving hardware costs.

[0032] In a possible implementation, the power division network includes a plurality of dual power dividers PD; the plurality of dual power dividers PD are connected layer by layer, and the number of output ends of the dual power dividers PD in the last layer is equal to the number of TR components, and are connected to the TR components one by one.

[0033] The design of the power division network is more modularized by connecting several two-power splitters PD layer by layer. This design facilitates system maintenance and upgrades. When the system needs to be expanded, you can simply add additional two-power splitter layers or modify the connection method to accommodate more TR components. In addition, the layer-by-layer connection method helps to simplify the wiring inside the system, reduce the loss and interference in the signal transmission path, and improve the stability and reliability of the system. At the same time, the two-power splitter is a mature RF component with a relatively low cost.

[0034] In a possible implementation, the TR component includes an adjustable attenuator ATT, a phase shifter PS, a first transceiver control switch SW1, a transmitting link power amplifier PA, a receiving link low noise amplifier LNA and a second transceiver control switch SW2; one end of the adjustable attenuator ATT is connected to the power division network, and the other end is connected to the adjustable attenuator ATT, the phase shifter PS, and the first end of the first transceiver control switch SW1 in sequence; the first end of the second transceiver control switch SW2 is connected to the pitch beamforming network BFN; the second end of the first transceiver control switch SW1 and the second end of the second transceiver control switch SW2 are respectively connected to the two ends of the transmitting link power amplifier PA, and the third end of the first transceiver control switch SW1 and the third end of the second transceiver control switch SW2 are respectively connected to the two ends of the receiving link low noise amplifier LNA.

[0035] Specifically, the adjustable attenuator ATT and the phase shifter PS provide flexible amplitude and phase control, which helps to achieve accurate beamforming and beam scanning. Through the first transceiver control switch SW1 and the second transceiver control switch SW2, the system can flexibly switch the transmit and receive modes to achieve efficient two-way communication. The receive link low noise amplifier LNA in the receive link can effectively reduce the noise level of the received signal and improve the receiving sensitivity and signal-to-noise ratio of the system. The transmit link power amplifier PA in the transmit link can provide sufficient transmit power to ensure that the signal can cover a longer distance.

[0036] In one possible implementation, see Figure 4The elevation beamforming network BFN ​​includes an internal power division network and a plurality of propagation delay components; one end of the internal power division network is connected to the TR component, and the other end is connected to one end of the plurality of propagation delay components, and the other ends of the plurality of propagation delay components are respectively connected to a plurality of antenna arrays ANT.

[0037] Specifically, the phase of the signal connected to each antenna array ANT can be precisely controlled through the propagation delay component. Phase control is the core of beamforming technology, which allows the system to adjust the relative phase difference of the signal in space, thereby changing the direction and shape of the beam. In the pitch direction, by setting different delay times for each antenna array ANT, it can be ensured that a wide beam with decreasing gain is formed in the far field, midfield to near field. Moreover, the phase of each antenna array ANT can be adjusted independently based on the independent propagation delay component, so various beamforming modes can be flexibly implemented. This can not only meet the long-distance communication requirements for air coverage, but also adjust the width, direction and gain distribution of the beam according to the needs of specific application scenarios to adapt to different communication environments and goals.

[0038] In a possible implementation, the internal power division network includes a plurality of two-power dividers PD; the plurality of two-power dividers PD are connected layer by layer, and the number of output ends of the last layer of two-power dividers PD is equal to the number of propagation delay components, and are connected to the plurality of propagation delay components one by one.

[0039] In a possible implementation manner, the propagation delay component is a microstrip line.

[0040] In the pitch beamforming network BFN, the phase of the signal can be precisely controlled by using microstrip lines as propagation delay components. By adjusting the length of the microstrip line, the phase difference between the antenna elements ANT can be precisely adjusted to control the direction and shape of the beam. In addition, since the microstrip line has controllable characteristic impedance and phase characteristics, various beamforming modes can be flexibly implemented. This helps the phased array system adjust the width, direction and gain distribution of the beam according to the needs of the actual application scenario. At the same time, using microstrip lines as propagation delay components can reduce the need for additional phase control elements, thereby simplifying system design and reducing system complexity. In addition, the integrated characteristics of the microstrip line also help to reduce the size and weight of the system.

[0041] In one possible implementation, the delays of the several propagation delay components are obtained in the following manner: based on the system link budget requirement, a transmitting antenna gain requirement at each elevation angle is obtained; based on the transmitting antenna gain requirement at each elevation angle, an optimal phase value at each elevation angle is obtained; based on the optimal phase value at each elevation angle, a delay at each elevation angle is obtained.

[0042] Optionally, taking the transmission pattern as an example, obtaining the transmission antenna gain requirement and the receiving antenna gain requirement at each elevation angle according to the system link budget requirement includes: The transmit antenna gain requirement at each elevation angle is obtained by the following formula: Gtx=L+M-(P+Grx-Sen) Among them, Gtx is the transmit antenna gain requirement, L is the link loss, M is the link margin, P is the transmit power, Sen is the sensitivity of the opposite end receiver, and Grx is the opposite end receive antenna gain.

[0043] The gain requirement in the receiving direction is similar to that in the transmitting direction. According to the system link budget requirement, the gain requirements of the receiving antenna at each elevation angle include: The receiving antenna gain requirement at each elevation angle is obtained by the following formula: Grx1=L+M-(P1+Gtx1-Sen1) Among them, Grx1 is the receiving antenna gain requirement, P1 is the peer transmit power, Sen1 is the receiver sensitivity, and Gtx1 is the peer transmit antenna gain.

[0044] Generally speaking, if the link is symmetrical, the array gain requirements in the transmit and receive directions are the same. If the requirements are asymmetrical, the antenna pattern constraints are generated according to the maximum gain requirement.

[0045] Optionally, obtaining the optimal phase value at each pitch angle according to the transmitting antenna gain requirement at each pitch angle includes: generating a target radiation pattern according to the transmitting antenna gain requirement at each pitch angle; obtaining a transmitting radiation pattern with a pitch angle of 0, and based on the target radiation pattern and the transmitting radiation pattern with a pitch angle of 0, taking minimizing the error between the radiation pattern generated based on the optimal phase and the target radiation pattern as the optimization goal and using a curve fitting algorithm to search for the optimal phase, to obtain a radiation pattern generated based on the optimal phase; and obtaining the optimal phase value at each pitch angle according to the radiation pattern generated based on the optimal phase.

[0046] For details, see Figure 5 In the figure, the blue curve is the transmission pattern with a pitch angle of 0, the yellow curve is the pattern generated based on the optimal phase, and the purple curve is the target pattern. When using the curve fitting algorithm to search for the optimal phase, an optimization algorithm such as a genetic algorithm or deep learning can be used.

[0047] Optionally, obtaining the delay at each pitch angle according to the optimal phase value at each pitch angle includes: obtaining the delay at each pitch angle by the following formula:

[0048] in, For delay, is the optimal phase value, c is the speed of light, and f is the working RF frequency.

[0049] Each propagation delay component is designed according to the delay, and then the phase of each antenna element ANT is adjusted, so as to realize the wide beamforming of the elevation beamforming network BFN ​​that takes into account the far field, mid field and near field.

[0050] See also Figure 6 , showing the elevation beam direction output by the phased array system suitable for air coverage of the present invention. It can be found that the directional diagram takes into account the gain requirements of the near field, midfield and far field areas, and there is no blind spot in the elevation coverage.

[0051] This method is applicable to the phased array system for air coverage. It adopts the array structure of multi-channel TR components and elevation beamforming network BFN. By pre-designing the phase of the antenna array source in the elevation direction, wide beam air coverage is achieved while taking into account the horizontal coverage of the far end. Compared with the traditional phased array system, it can effectively reduce the number of TR components and has the advantages of simple circuit structure and low cost.

[0052] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A phased array system suitable for air coverage, characterized in that: It includes a power division network and a plurality of TR components connected to one end of the power division network; one end of each TR component away from the power division network is connected in sequence to a pitch beam forming network BFN ​​and a plurality of antenna arrays ANT; The elevation beamforming network BFN ​​is used to generate a wide beam in the elevation direction through a plurality of antenna arrays ANT in a fixed beamforming manner, wherein the gain decreases successively along the directions of the far field, the midfield and the near field.

2. The phased array system suitable for air coverage according to claim 1, characterized in that: The power division network includes a plurality of power dividers PD; The plurality of two-power dividers PD are connected layer by layer, and the number of output ends of the two-power dividers PD in the last layer is equal to the number of the plurality of TR components, and are connected to the plurality of TR components one by one.

3. The phased array system suitable for air coverage according to claim 1, characterized in that: The TR component includes an adjustable attenuator ATT, a phase shifter PS, a first transceiver control switch SW1, a transmission link power amplifier PA, a reception link low noise amplifier LNA and a second transceiver control switch SW2; One end of the adjustable attenuator ATT is connected to the power division network, and the other end is connected to the adjustable attenuator ATT, the phase shifter PS, and the first end of the first transceiver control switch SW1 in sequence; The first end of the second transceiver control switch SW2 is connected to the pitch beamforming network BFN; the second end of the first transceiver control switch SW1 and the second end of the second transceiver control switch SW2 are respectively connected to the two ends of the transmitting link power amplifier PA, and the third end of the first transceiver control switch SW1 and the third end of the second transceiver control switch SW2 are respectively connected to the two ends of the receiving link low noise amplifier LNA.

4. The phased array system suitable for air coverage according to claim 1, characterized in that: The elevation beamforming network BFN ​​includes an internal power distribution network and a plurality of propagation delay components; One end of the internal power distribution network is connected to the TR component, and the other end is connected to one end of a plurality of propagation delay components. The other ends of the plurality of propagation delay components are respectively connected to a plurality of antenna elements ANT.

5. The phased array system suitable for air coverage according to claim 1, characterized in that: The internal power division network includes a plurality of dual power dividers PD; The plurality of two-power dividers PD are connected layer by layer, and the number of output terminals of the two-power dividers PD in the last layer is equal to the number of the plurality of propagation delay components, and are connected to the plurality of propagation delay components one by one.

6. The phased array system suitable for air coverage according to claim 4, characterized in that: The propagation delay component is a microstrip line.

7. The phased array system suitable for air coverage according to claim 4, characterized in that: The delays of the several propagation delay components are obtained as follows: According to the system link budget requirements, the transmitting antenna gain requirements and the receiving antenna gain requirements at each elevation angle are obtained; According to the transmitting antenna gain requirement and the receiving antenna gain requirement at each elevation angle, the optimal phase value at each elevation angle is obtained; According to the optimal phase value at each pitch angle, the delay at each pitch angle is obtained.

8. The phased array system suitable for air coverage according to claim 7, characterized in that: The obtaining of the transmitting antenna gain requirement and the receiving antenna gain requirement at each elevation angle according to the system link budget requirement includes: The transmit antenna gain requirement at each elevation angle is obtained by the following formula: Gtx=L+M-(P+Grx-Sen) Where Gtx is the transmit antenna gain requirement, L is the link loss, M is the link margin, P is the transmit power, Sen is the receiver sensitivity of the other end, and Grx is the receive antenna gain of the other end; The receiving antenna gain requirement at each elevation angle is obtained by the following formula: Grx1=L+M-(P1+Gtx1-Sen1) Among them, Grx1 is the receiving antenna gain requirement, P1 is the peer transmit power, Sen1 is the receiver sensitivity, and Gtx1 is the peer transmit antenna gain.

9. The phased array system suitable for air coverage according to claim 7, characterized in that: The obtaining of the optimal phase value at each elevation angle according to the transmit antenna gain requirement at each elevation angle includes: Generate target radiation pattern according to the transmit antenna gain requirement at each elevation angle; Taking the minimum error between the directional pattern generated based on the optimal phase and the target directional pattern as the optimization goal and using the curve fitting algorithm to search for the optimal phase, the directional pattern generated based on the optimal phase is obtained; According to the directional diagram generated based on the optimal phase, the optimal phase value at each pitch angle is obtained.

10. The phased array system suitable for air coverage according to claim 7, characterized in that: The step of obtaining the delay at each pitch angle according to the optimal phase value at each pitch angle comprises: The delay at each pitch angle is obtained by the following formula: in, For delay, is the optimal phase value, c is the speed of light, and f is the working RF frequency.

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