X-band two-dimensional phased array radar

Abstract

The invention relates to an X-band two-dimensional phased array radar which comprises a microstrip antenna transmitting and receiving antenna subarray, a power distribution / synthesis network, a digital T / R assembly, a frequency source, a wave control unit, a servo turntable, a terminal server and the like. A sub-array modular design is adopted for receiving and transmitting of a radar microstrip antenna, a 4 * 4 array is used as a basic sub-array unit for array expansion to achieve a 32 * 32 array, and the total number of channels is 1024. The detection capability of an original phased array weather radar on a local meteorological target can be improved, the problem that a traditional phased array radar is large in size and difficult to maintain is solved, electric scanning can be conducted in the azimuth direction and the pitching direction, meanwhile, the mechanical scanning capability is achieved, high-precision rainfall monitoring of the scene can be achieved through two-dimensional electric scanning of the vertical headspace, and the application range is wide. Therefore, the detection efficiency of the phased array radar is greatly improved, and real-time monitoring and scanning of a specified target are realized.

Description

Technical Field

[0001] The present invention relates to the field of radars, and in particular to an X-band two-dimensional phased array radar. Background Art

[0002] Currently, the main X-band weather radars are mechanical scanning type and one-dimensional phased array type. Among them, mechanical scanning weather radar can meet the basic rainfall monitoring and early warning forecasting functions, but its scanning speed is slow compared with phased array weather radar. It usually takes more than 6 minutes to scan the entire airspace, and there is a cone of silence in the scanning range. The mechanical scanning X-band weather radar is heavy and has certain requirements for installation and erection. The one-dimensional phased array radar uses one-dimensional electronic scanning, usually scanning in azimuth by mechanical rotation of a turntable, and electronic scanning in elevation. Compared with the mechanical scanning radar, the rainfall accuracy and temporal and spatial resolution are improved, but as the complexity of the phased array radar increases, its weight and volume increase a lot compared with the mechanical scanning radar, making it difficult to erect and costly. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an X-band two-dimensional phased array radar to solve the deficiencies of the prior art.

[0004] The object of the present invention is achieved by the following technical solutions: an X-band two-dimensional phased array radar, which includes 2m microstrip antenna transceiver subarrays, a power distribution / synthesis network, a digital T / R component, a frequency source, a wave control unit, a servo turntable and a terminal server; During the signal transmission process, the frequency source feeds m-way transmission excitation signals, which are split through a four-way power splitter and synthesizer network. Under the control of the transmission beam transmitted by the beam control unit, the multifunctional amplitude and phase control circuit completes the signal splitting, phase shifting and amplification processing, and finally sends them to each transmitting array element to complete the signal transmission. During the signal reception process, the receiving array element sends the received RF signal to the four-way power synthesis network. The power division and synthesis network synthesizes the signal of each row of the antenna array to the output interface of each row. Under the control of the receiving beam of the beam control unit, the phase shift processing of the received signal is realized, and then the power distribution / synthesis network completes the synthesis of the received signal and outputs it to the m-way receiving port of the digital T / R component.

[0005] The microstrip antenna transceiver subarray comprises an antenna array surface, a four-way power division and synthesis network and a multifunctional amplitude and phase control circuit. Each microstrip antenna transceiver subarray outputs a feeding interface, and then m microstrip antenna transceiver subarrays form a two-dimensional array system. The two-dimensional array system realizes transceiver and electric scanning in the azimuth direction through the multifunctional amplitude and phase control circuit and the four-way power division and synthesis network, realizes transmit electric scanning in the elevation direction by controlling the transmit signal amplitude and phase value of the m feed interfaces, and receives electric scanning in the elevation direction is realized by processing by a terminal server.

[0006] When the device is powered on, the microstrip antenna transceiver array is in the receiving state. The wave control unit calculates the phase shift code value of each unit according to the azimuth, elevation and frequency information transmitted by the terminal server, and then sets the phase shift parameter by controlling the signal level. At this time, the high-frequency signal excites different current directions on each antenna array surface for in-phase superposition. The current is power synthesized through their respective power division and synthesis networks and finally output.

[0007] For the transmitting array, the sidelobe level requirements of the transmitting array are achieved under the premise of meeting the array gain and beam width, and the array structure sidelobe weighting is achieved by closing the antenna array surface under the rectangular array layout; For the receiving array, under the premise of ensuring the array gain and beam width, the array's low sidelobe beam requirement is achieved by sampling Taylor amplitude weighting.

[0008] The terminal server sends operating mode and beam pointing instructions to the beam control unit through the control serial port. After parsing the instructions, the beam control unit controls the digital T / R component to shift it to the required phase and frequency to achieve the purpose of beam switching. The beam control unit sends the antenna status information to the terminal server through the control serial port.

[0009] The four-way power division and synthesis network includes a four-channel beamforming chip, which includes 1 common port and 4 transmit-receive common ports, a corresponding 1:4 power division and synthesis network and 4 transmit-receive channels, and each transmit-receive channel integrates a high-power RF switch, a power amplifier, a limiting low-noise amplifier, a 6-bit digital phase shifter and a 5-bit / 6-bit digitally controlled attenuator.

[0010] The antenna array is used to complete the transmission and reception of radio frequency signals, the multifunctional amplitude and phase control circuit is used for phase shifting, amplification and filtering of radio frequency signals, the four-way power division and synthesis network is used to control the distribution of radio frequency signals, and realizes beam scanning of the phased array antenna according to instructions.

[0011] The servo system is used to place the antenna array horizontally so that the antenna array faces the overhead space. High-precision local rainfall monitoring is achieved by performing two-dimensional electrical scanning on the vertical overhead space area. The servo turntable does not need to rotate during the scanning process.

[0012] The invention has the following advantages: an X-band two-dimensional phased array radar, which adopts radio frequency modular technology to integrate the antenna array surface and the transceiver component into an integrated design to realize the miniaturization, lightness and low cost of the phased array antenna; the array structure sidelobe weighting is realized by closing the array elements to realize the transmission sidelobe level requirement under the conditions of satisfying the array gain and beam width, and the Taylor amplitude weighting is realized at the receiving end to realize the low sidelobe beam requirement under the premise of ensuring the gain and beam width during reception; the two-dimensional electronic scanning function is realized by controlling the amplitude and phase of each row of antenna units in each subarray, and the radar detection efficiency is greatly improved without reducing the radar detection capability, and the slight change in the position of the radar when transmitting and receiving pulses during mechanical rotation is eliminated, which introduces additional phase errors, destroys the phase consistency between signals, and affects the coherent accumulation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 This is a schematic diagram of the layout of microstrip antennas; Figure 3 Schematic diagram of the beam control process; Figure 4 Schematic diagram of microstrip antenna subarray; Figure 5 It is a schematic diagram of a four-way power division and synthesis network; Figure 6 This is a schematic diagram of rainfall monitoring in this area. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of the present application provided below in conjunction with the drawings is not intended to limit the scope of protection of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application. The present invention is further described below in conjunction with the drawings.

[0015] like Figure 1As shown, the present invention specifically relates to an X-band two-dimensional phased array radar, which can improve the detection capability of the original phased array weather radar for local meteorological targets, solve the problem that the traditional phased array radar is large and difficult to maintain, and has the ability to perform electronic scanning in both azimuth and elevation directions and mechanical scanning at the same time, and can realize high-precision local rainfall monitoring through two-dimensional electronic scanning of the vertical overhead space, thereby greatly improving the detection efficiency of the phased array radar and realizing real-time monitoring and scanning of the designated target; it includes components such as microstrip antenna transceiver antenna subarray, power distribution / synthesis network, digital T / R component, frequency source, wave control unit, servo turntable and terminal server. The radar microstrip antenna transceiver adopts subarray modular design, and uses 4×4 array as the basic subarray unit to expand the array to realize 32×32 array, with a total of 1024 channels.

[0016] The digital T / R component feeds 32 transmission excitation signals, which are divided through a four-way power splitter and synthesizer network. Under the transmission beam control signal transmitted by the beam control unit, the multifunctional amplitude and phase control circuit completes the signal division, phase shifting and amplification processing, and finally sends it to each antenna array to complete the signal transmission. For the receiving link, after the receiving array element receives the RF signal, it is sent to the four-way power synthesis network. The power splitter and synthesis network synthesizes the signal of each row of the antenna array to each row of the output interface. Under the control of the receiving beam of the beam control unit, the phase shift processing of the received signal is realized and the signal synthesis is completed, and it is output to the 32-way receiving port of the digital T / R component.

[0017] When the device is powered on, the power module inside the antenna transceiver array supplies power to each active module of the antenna. At this time, the antenna is in the receiving state. The wave control unit calculates the phase shift code value of each antenna transceiver array according to the azimuth, elevation, and frequency information transmitted by the terminal, and then sets the phase shift parameter by controlling the signal level. At this time, the signal coming from the specified direction excites different currents on each antenna array surface to be superimposed in phase. The currents are combined through their respective power division and synthesis networks for power synthesis and finally output.

[0018] The antenna array surface, multifunctional amplitude and phase control circuit, and power division synthesis network of each row of the phased array radar microstrip array system of the present invention form a single-row subarray, each row outputs a feed interface, and then 32 row subarrays form a two-dimensional array system (64 4x4 subarrays are arranged in a rectangular 8×8 pattern, forming an antenna array surface with 32 rows and 32 columns). The array system can realize azimuth transmission and reception scanning by the multifunctional amplitude and phase control circuit and the power division synthesis network; the transmission electronic scanning in the elevation direction can be realized by controlling the amplitude and phase value of the transmission signal of the 32 feed ports; the reception electronic scanning in the elevation direction is realized by the back-end digital part processing.

[0019] The antenna transceiver unit mainly completes the transmission and reception of RF signals, and the multifunctional amplitude and phase control circuit mainly includes the functions of phase shifting, amplification and filtering of RF signals. The four-way power division and synthesis network controls the RF signal distribution of the antenna transceiver subarray, and realizes the beam scanning of the phased array antenna according to the instructions.

[0020] Among them, both the transmitting antenna unit and the receiving antenna unit are implemented with the same rectangular patch structure with dual-wire probe feeding. The impedance bandwidth of the antenna unit covers the operating frequency band of 9300MHz~9500MHz, and the gain of the antenna unit within the range of ±120° is >0dBi. It not only has good impedance bandwidth, but also has relatively ideal beam characteristics.

[0021] The present invention arranges 64 4×4 sub-arrays in a matrix to form a 32×32 antenna array with a total of 1024 channels. The antenna sub-array schematic diagram is shown in FIG. Figure 4 shown.

[0022] like Figure 5 As shown in the figure, the four-way power splitter and combiner network uses a four-channel beamforming chip, which covers an operating frequency of 8~12GHz and supports TDD time division duplex mode. The chip has a total of 5 RF ports: 1 common port, 4 ports shared by both transmit and receive, with a built-in corresponding 1:4 power splitter and combiner network and 4 transmit and receive channels. Each transmit and receive channel integrates functional circuits such as high-power RF switch, power amplifier, limiting low noise amplifier, 6-bit digital phase shifter, 5-bit / 6-bit digital controlled attenuator, etc.

[0023] like Figure 2 As shown in the figure, for the transmitting array, the sidelobe level requirement of the transmitting array is achieved under the premise of meeting the array gain and beam width. The array structure sidelobe weighting is achieved by closing the array surface under the rectangular array layout. Each vertex of the 32×32 rectangular array closes 2 subarrays (2×4×4), and a total of 8 subarrays and 128 units are closed. For the receiving array, under the premise of ensuring the array gain and beam width, the low sidelobe beam requirement of the array is achieved by adopting Taylor amplitude weighting.

[0024] like Figure 3 As shown, the terminal server sends the working mode, beam pointing and other instructions to the beam control unit through the control serial port. After parsing the instructions, the beam control unit controls the T / R component to shift it to the required phase and frequency to achieve the purpose of beam switching. The beam control unit sends the antenna status information to the terminal server through the serial port.

[0025] By controlling the phase of each antenna transceiver subarray, two-dimensional electronic scanning of ±36° in elevation and ±45° in azimuth can be achieved, significantly improving detection efficiency.

[0026] The present invention adopts the design concept of high-density integration of sampling RF+control+power SIP, based on the design of 4×4 standard antenna transceiver subarray module, using 4×8 subarray modules to share a power distribution / synthesis network, and providing appropriate power supply, control, and primary power distribution for the subarray module. The functions that traditional phased array radars need to complete, such as RF, control, and power supply, are completed in only one subarray. While increasing the transceiver channels of the phased array radar, the number of modules is reduced, which greatly reduces the volume and weight of the radar, reducing the weight of the whole machine to less than 80kg, improving the transportability and installation efficiency of the phased array radar, reducing the requirements of the phased array radar for the erection of infrastructure, and realizing the miniaturization, lightness, and low cost of the phased array antenna.

[0027] like Figure 6 As shown, the present invention places the antenna array horizontally through the servo system so that the antenna array is facing the overhead space. By performing two-dimensional electrical scanning on the vertical overhead space area, high-precision local rainfall monitoring of 11.6km² (4km×2.9km) can be achieved. During the scanning process, the servo turntable does not need to rotate, eliminating the problem that the local static cone area of ​​the traditional mechanical scanning radar and one-dimensional phased array radar cannot be monitored, and realizing high-precision rainfall monitoring of the radar vertical overhead space.

[0028] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used for various other combinations, modifications and improvements, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. An X-band two-dimensional phased array radar, characterized in that: It includes 2m microstrip antenna transceiver subarrays, power distribution / synthesis network, digital T / R components, frequency source, wave control unit, servo turntable and terminal server; During the signal transmission process, the frequency source feeds m-way transmission excitation signals, which are split through a four-way power splitter and synthesizer network. Under the control of the transmission beam transmitted by the beam control unit, the multifunctional amplitude and phase control circuit completes the signal splitting, phase shifting and amplification processing, and finally sends them to each transmitting array element to complete the signal transmission. During the signal reception process, the receiving array element sends the received RF signal to the four-way power synthesis network. The power division and synthesis network synthesizes the signal of each row of the antenna array to the output interface of each row. Under the control of the receiving beam of the beam control unit, the phase shift processing of the received signal is realized, and then the power distribution / synthesis network completes the synthesis of the received signal and outputs it to the m-way receiving port of the digital T / R component.

2. The X-band two-dimensional phased array radar according to claim 1, characterized in that: The microstrip antenna transceiver subarray comprises an antenna array surface, a four-way power division and synthesis network and a multifunctional amplitude and phase control circuit. Each microstrip antenna transceiver subarray outputs a feeding interface, and then m microstrip antenna transceiver subarrays form a two-dimensional array system. The two-dimensional array system realizes transceiver and electric scanning in the azimuth direction through the multifunctional amplitude and phase control circuit and the four-way power division and synthesis network, realizes transmit electric scanning in the elevation direction by controlling the transmit signal amplitude and phase value of the m feed interfaces, and receives electric scanning in the elevation direction is realized by processing by a terminal server.

3. The X-band two-dimensional phased array radar according to claim 1, characterized in that: When the device is powered on, the microstrip antenna transceiver array is in the receiving state. The wave control unit calculates the phase shift code value of each unit according to the azimuth, elevation and frequency information transmitted by the terminal server, and then sets the phase shift parameter by controlling the signal level. At this time, the high-frequency signal excites different current directions on each antenna array surface for in-phase superposition. The current is power synthesized through their respective power division and synthesis networks and finally output.

4. The X-band two-dimensional phased array radar according to claim 3, characterized in that: For the transmitting array, the sidelobe level requirements of the transmitting array are achieved under the premise of meeting the array gain and beam width, and the array structure sidelobe weighting is achieved by closing the antenna array surface under the rectangular array layout; For the receiving array, under the premise of ensuring the array gain and beam width, the array's low sidelobe beam requirement is achieved by sampling Taylor amplitude weighting.

5. The X-band two-dimensional phased array radar according to claim 1, characterized in that: The terminal server sends operating mode and beam pointing instructions to the beam control unit through the control serial port. After parsing the instructions, the beam control unit controls the digital T / R component to shift it to the required phase and frequency to achieve the purpose of beam switching. The beam control unit sends the antenna status information to the terminal server through the control serial port.

6. The X-band two-dimensional phased array radar according to claim 2, characterized in that: The four-way power division and synthesis network includes a four-channel beamforming chip, which includes 1 common port and 4 transmit-receive common ports, a corresponding 1:4 power division and synthesis network and 4 transmit-receive channels, and each transmit-receive channel integrates a high-power RF switch, a power amplifier, a limiting low-noise amplifier, a 6-bit digital phase shifter and a 5-bit / 6-bit digitally controlled attenuator.

7. The X-band two-dimensional phased array radar according to claim 2, characterized in that: The antenna array is used to complete the transmission and reception of radio frequency signals, the multifunctional amplitude and phase control circuit is used for phase shifting, amplification and filtering of radio frequency signals, the four-way power division and synthesis network is used to control the distribution of radio frequency signals, and realizes beam scanning of the phased array antenna according to instructions.

8. The X-band two-dimensional phased array radar according to claim 1, characterized in that: The servo system is used to place the antenna array horizontally so that the antenna array faces the overhead space. High-precision local rainfall monitoring is achieved by performing two-dimensional electrical scanning on the vertical overhead space area. The servo turntable does not need to rotate during the scanning process.

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