A dual-polarization phased array weather radar

Abstract

The present invention relates to a dual-polarization phased array antenna and a dual-polarization phased array weather radar. Among them, the dual-polarization phased array antenna arranges multiple dual-polarization line feeds on a transverse cylindrical support surface to form a transverse cylindrical dual-polarization (polarization) microstrip patch antenna, thereby realizing the simultaneous transmission and reception of two polarization (polarization) signals in the horizontal and vertical directions, and can ensure a digital multi-beam signal with unchanged beam width, unchanged antenna gain, and unchanged dual-polarization performance. The dual-polarization phased array weather radar provided by the present invention adopts the transverse cylindrical dual-polarization (polarization) microstrip patch antenna formed as described above, which can ensure the consistency of weather detection at different scanning angles and improve the accuracy of three-dimensional construction of weather targets. At the same time, it can simplify the requirements for calibration of existing phased array weather radars and improve the adaptability of dual-polarization phased array weather radars.

Description

Technical Field

[0001] The present invention relates to the field of weather detection devices, and in particular to a dual-polarization phased array antenna and a dual-polarization phased array weather radar. Background Art

[0002] Since the advent of radar technology, research into its use in meteorological detection has been continuously developing. Weather radar is the most effective means of detecting and warning of various types of hazardous weather. Many countries around the world have established weather radar networks, and my country has also established a new generation of weather radar networks. Currently, operational weather radars generally use mechanical scanning, which takes approximately six minutes to complete a single volume scan, making it difficult to detect rapidly changing weather phenomena. Phased array weather radars use electronic scanning, which has scanning speeds unrestricted by mechanical rotational performance and can operate multiple beams simultaneously. Therefore, the use of phased array weather radars for rapid detection has become the mainstream of next-generation weather radar development.

[0003] Dual-polarization detection technology can obtain more parameters of meteorological targets, better identify them, and provide more accurate weather information. Therefore, the use of dual-polarization detection has become a consensus in the field of meteorological radar. Combining phased array weather radar with dual-polarization technology creates a fast-scanning dual-polarization phased array weather radar, overcoming the shortcomings of current weather radars and achieving multifunctional detection.

[0004] Phased array antenna array configurations generally include one-dimensional linear arrays, two-dimensional planar arrays, and spherical arrays.

[0005] One-dimensional linear arrays are generally electronically scanned in azimuth or elevation, and mechanically rotated in the other dimension to complete weather detection in the entire airspace. Two-dimensional planar array antennas require multiple array surfaces (usually three or four surfaces), which is relatively expensive. Both one-dimensional linear arrays and two-dimensional planar arrays have the characteristic of nonlinear changes in various beam parameters when the beam pointing deviates from the normal. As the beam scanning angle changes, the beam width of the one-dimensional linear array or two-dimensional planar array changes, the antenna gain changes, the radar illumination volume also changes, and the polarization direction of the beam also changes and distorts, and this change is nonlinear. Spherical arrays are the best among phased array radars. The beam can be flexibly controlled and is consistent in all beam directions, but its manufacturing cost is also the highest. To address the nonlinear changes in various parameters during planar phased array beam scanning, the U.S. patent "Cylindrical Polarimetric Phased Array Radar" (patent number US 2011 / 0285582A1) proposed a vertical cylindrical phased array weather radar to ensure that the various indicators of the radar beam remain stable during azimuth scanning. However, this method still has nonlinear changes in the beam during pitch scanning, and the pitch scanning angle is limited, and it cannot scan the zenith direction. Summary of the Invention

[0006] The purpose of the present invention is to provide a dual-polarization phased array antenna and a dual-polarization phased array weather radar to achieve unchanged scanning of beam performance and effectively improve the accuracy of weather detection and target recognition.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] A dual-polarization phased array antenna, comprising: a transverse cylindrical support surface, a support frame, and a plurality of dual-polarization line feeds;

[0009] The support frame is matched with the transverse cylindrical support surface; the support frame is used to support the transverse cylindrical support surface;

[0010] The plurality of dual-polarization line feeds are arranged on the transverse cylindrical support surface, and the plurality of dual-polarization line feeds are closely arranged along the circumferential direction of the transverse cylindrical support surface.

[0011] Preferably, it also includes: a digital transceiver module;

[0012] The digital transceiver module includes a plurality of dual-channel digital T / R components;

[0013] Each of the dual-polarization line feeds corresponds to one of the dual-channel digital T / R components; the dual-channel digital T / R component is used for transmitting and receiving signals.

[0014] Preferably, the dual-channel digital T / R assembly includes a digital receiving unit and a digital transmitting unit;

[0015] The digital transmitting unit is used to generate a frequency modulation signal or a phase coding signal required for detecting a target; and the digital receiving unit is used to receive an echo signal reflected back by the target.

[0016] Preferably, the digital transmitting unit is a fully solid-state transmitter.

[0017] Preferably, each of the dual-polarized line feeds includes a plurality of line feed inner sub-arrays; each of the line feed inner sub-arrays includes an electronic switch and a plurality of antenna radiating units;

[0018] The electronic switch is connected to the antenna radiation unit; the electronic switch is used to turn on and off the antenna radiation unit.

[0019] Preferably, it further comprises: a driving module;

[0020] The driving module is connected to the supporting frame to drive the supporting frame to rotate horizontally.

[0021] Preferably, the driving module includes: a driving motor, an angle encoder and a motor control unit;

[0022] The angle encoder and the drive motor are both connected to the motor control unit;

[0023] The motor control unit is used to control the driving motor to drive the support frame to rotate to a specified angle according to the angle information in the angle encoder.

[0024] A dual-polarization phased array weather radar, comprising: an information processing module and the dual-polarization phased array antenna;

[0025] The information processing module is connected to the dual-polarization phased array antenna; the information processing module is used to perform spectrum analysis based on the signal received by the dual-polarization phased array antenna to obtain target echo information; the information processing module is also used to generate control instructions to drive the dual-polarization phased array antenna to perform signal acquisition in the horizontal direction and / or signal acquisition in the pitch direction.

[0026] Preferably, the information processing module is connected to the electronic switch in the dual-polarization phased array antenna; the information processing module is used to control the opening and closing of the electronic switch, and the dual-polarization phased array antenna forms electronic scanning at different angles in the pitch direction according to the area where the electronic switch is turned on.

[0027] Preferably, the information processing module includes: a multi-channel DBF module, a signal processing module and a communication module;

[0028] The multi-channel DBF module is connected to the signal processing module; the signal processing module is connected to the communication module;

[0029] The multi-channel DBF module is used to convert the echo signal received by the dual-polarization phased array antenna into a beam signal; the signal processing module is used to obtain target echo information after performing spectrum analysis on the beam signal; and the communication module is used to send the target echo information.

[0030] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0031] The dual-polarization phased array antenna provided by the present invention arranges multiple dual-polarization line feeds on a transverse cylindrical support surface to form a transverse cylindrical dual-polarization (polarization) microstrip patch antenna, thereby realizing the simultaneous transmission and reception of two polarization (polarization) signals in the horizontal and vertical directions, and can ensure a digital multi-beam signal with unchanged beam width, unchanged antenna gain, and unchanged dual-polarization performance.

[0032] The dual-polarization phased array weather radar provided by the present invention utilizes the aforementioned horizontal cylindrical dual-polarization (polarization) microstrip patch antenna, ensuring consistent weather detection at different scanning angles and improving the accuracy of three-dimensional weather target reconstruction. Furthermore, it simplifies the calibration requirements of existing phased array weather radars and improves their adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 A schematic structural diagram of the dual-polarization phased array antenna provided by the present invention;

[0035] Figure 2 A schematic diagram of the structure of the dual-polarization phased array weather radar provided by the present invention;

[0036] Figure 3 A structural diagram of the dual-polarization phased array weather radar provided by the present invention, including a dual-polarization phased array antenna;

[0037] Figure 4 A schematic diagram of radar beam transmission provided by the present invention;

[0038] Figure 5 is a directional pattern of a horizontal line-fed azimuth beam of a dual-polarized line feed in an embodiment of the present invention;

[0039] Figure 6 is the directional pattern of the elevation transmission beam in an embodiment of the present invention;

[0040] Figure 7 Schematic diagram of the elevation receive beam in an embodiment of the present invention.

[0041] Explanation of symbols:

[0042] 1- horizontal cylindrical support surface, 2- support frame, 3- dual-polarization line feed, 4- digital transceiver module, 5- information processing module, 6- cabinet. DETAILED DESCRIPTION

[0043] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0044] The purpose of the present invention is to provide a dual-polarization phased array antenna and a dual-polarization phased array weather radar to achieve unchanged scanning of beam performance and effectively improve the accuracy of weather detection and target recognition.

[0045] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0046] Figure 1 This is a schematic structural diagram of the dual-polarization phased array antenna provided by the present invention. Figure 3 The structure diagram of the dual polarization phased array weather radar provided by the present invention includes a dual polarization phased array antenna. Figure 1 and Figure 3 As shown, the dual-polarization phased array antenna provided by the present invention includes: a transverse cylindrical supporting surface 1, a supporting frame 2 and a plurality of dual-polarization line feeds 3.

[0047] The support frame 2 is matched with the horizontal cylindrical support surface 1 (such as Figure 3 The support frame 2 is used to support the transverse cylindrical support surface 1.

[0048] The plurality of dual-polarization line feeds 3 are arranged on the transverse cylindrical support surface 1, and the plurality of dual-polarization line feeds 3 are closely arranged along the circumferential direction of the transverse cylindrical support surface 1 (eg Figure 1 shown).

[0049] As a further optimization of the embodiment provided by the present invention, the dual-polarization phased array antenna further includes a digital transceiver module 4 .

[0050] The digital transceiver module 4 includes a plurality of dual-channel digital T / R components.

[0051] Each dual-polarized line feed corresponds to a dual-channel digital T / R module. The dual-channel digital T / R module is used to transmit and receive signals. This means that each digital transceiver module 4 channel corresponds one-to-one with each dual-polarized line feed 3. That is, each line feed is connected to one digital transceiver module 4, which implements the following functions:

[0052] 1) During transmission, a direct digital synthesizer (DDS) generates, up-converts, and amplifies the transmission excitation signal, which is then fed to the transmission channel in the transceiver module via a line feed network to generate a high-power transmission signal.

[0053] 2) During reception, the dual-polarized antenna receiving signal is synthesized through the feed network and sent to the receiving channel of the digital transceiver module 4. After amplification, filtering, down-conversion and A / D sampling, it is converted into a digital receiving signal and sent to the software information processing module 5 via optical fiber.

[0054] 3) By selecting the pitch direction digital transceiver component channel, the beam electronic scanning of the pitch direction arc phased array is realized.

[0055] 4) The digital beam forming (DBF) in the software-based information processing module 5 is used to realize multi-beam reception in elevation.

[0056] The dual-channel digital T / R assembly includes a digital receiving unit and a digital transmitting unit. The digital transmitting unit is preferably, but not limited to, a fully solid-state transmitter. The digital receiving unit is a signal receiving component that matches the digital transmitting unit. Any digital receiver capable of receiving digital signals can be used as the digital receiving unit in the present invention, but a digital receiving patch is preferably used.

[0057] The digital transmitting unit is used to generate the frequency modulation signal or phase coding signal required for detecting the target. The digital receiving unit is used to receive the echo signal reflected by the target.

[0058] In the present invention, to enable electronic scanning within a range of -2° to +182° in elevation, each of the aforementioned dual-polarization line feeds in the embodiments provided herein needs to include multiple line feed sub-arrays. Each line feed sub-array includes an electronic switch and multiple antenna radiating elements. Adjacent antenna radiating elements can be arranged in a rectangular or triangular configuration.

[0059] The electronic switch is connected to the antenna radiating unit and is used to turn on and off the antenna radiating unit, so as to form electronic scanning ranges of different angles in the pitch (vertical) direction by turning on different antenna radiating units.

[0060] In the horizontal direction, the present invention adopts mechanical scanning. In order to achieve 360° rotation scanning in the horizontal direction, the dual-polarization phased array antenna provided by the present invention needs to further include a driving module.

[0061] The driving module is connected to the support frame 2 to drive the support frame 2 to rotate horizontally within a range of 360°.

[0062] Among them, the driver module ( Figure 2 The servo transmission system in the system includes: drive motor, angle encoder and motor control unit.

[0063] The angle encoder and the drive motor are both connected to the motor control unit.

[0064] The motor control unit is used to control the driving motor to drive the support frame 2 to rotate to a specified angle or position according to the angle information in the angle encoder.

[0065] The radar beam transmission path of the present invention is as follows: Figure 4 shown.

[0066] The horizontal cylindrical dual-polarization phased array antenna provided by the present invention uses a dual-polarization (polarization) microstrip patch (dual-polarization line feed 3) antenna, which can simultaneously transmit and receive horizontal and vertical polarization (polarization) signals. The dual-polarization line feed 3 is arranged at equal intervals in the azimuth direction to form a horizontal linear array. The feed network of the line feed implements Taylor amplitude weighting to ensure that the antenna side lobe in azimuth is less than -30dB or lower (such as Figure 5 shown).

[0067] When dual-polarization is in operation, the horizontally polarized and vertically polarized transmission waveforms can be the same, or they can use orthogonal encoding to improve the isolation between the two channels when dual-polarization is in operation.

[0068] As another embodiment of the present invention, the present invention also provides a dual-polarization phased array weather radar including the dual-polarization phased array antenna, wherein the dual-polarization phased array weather radar adopts a pulse compression Doppler system. Figure 2 As shown, the dual-polarization phased array weather radar further includes: an information processing module 5.

[0069] The information processing module 5 is connected to the dual-polarization phased array antenna. The information processing module 5 is configured to perform spectrum analysis based on the signals received by the dual-polarization phased array antenna to obtain target echo information. The information processing module 5 is also configured to generate control instructions to drive the dual-polarization phased array antenna to collect signals in the horizontal direction and / or in the elevation direction.

[0070] The information processing module 5 is connected to the electronic switch in the dual-polarization phased array antenna. The information processing module 5 is used to control the opening and closing of the electronic switch. The dual-polarization phased array antenna forms electronic scanning at different angles in the pitch direction according to the area where the electronic switch is turned on.

[0071] In addition, the information processing module 5 may further include a timing unit to generate a full-machine timing signal of the dual-polarization phased array weather radar and an excitation signal sent to the transmitting module in the dual-polarization phased array antenna.

[0072] The information processing module 5 includes: a multi-channel DBF module, a signal processing module and a communication module.

[0073] The multi-channel DBF module is connected to the signal processing module. The signal processing module is connected to the communication module.

[0074] The multi-channel DBF module receives multiple received signals (signals from multiple horizontal line feeds) from the digital transceiver module 4 in the dual-polarization phased array antenna, forms single-beam or multi-beam signals, and then transmits these signals to the signal processing module. The signal processing module processes these signals to perform spectrum analysis. Since spectrum analysis is a well-known technique, this invention will not be described in detail here.

[0075] As a preferred embodiment of the present invention, a box 6 can be provided on the support frame 2 of the dual-polarization phased array antenna provided by the present invention, such as Figure 3 As shown, the information processing module 5 can be placed in the box 6 to avoid interference from external factors.

[0076] The support frame 2 can be fixed in different ways according to different geographical conditions of the location to be measured. In the present invention, it is preferably fixed by rivets.

[0077] In addition, the dual-polarization phased array weather radar provided by the present invention also includes a power distribution system for providing electrical energy to the entire radar. The power distribution system is preferably a solar power supply system or a mains power supply system.

[0078] A one-dimensional horizontal line feed is selected as the dual-polarization line feed 3 to illustrate the specific working process of the dual-polarization phased array antenna and the dual-polarization phased array weather radar provided by the present invention.

[0079] The dual-polarization phased array antenna of this invention has a horizontal cylindrical structure, consisting of 258 one-dimensional dual-polarization horizontal linear array row feeds arranged in the elevation direction along a cylindrical arc. Every 112 adjacent row feeds form an effective illumination aperture, enabling a pitch beam scan of ≤1°. The entire antenna has a scanning range of -2 to 182°.

[0080] First, the signal processing module receives external instructions or sets the working parameters according to the radar's built-in parameters, generates the timing signals required for the entire machine to operate according to the received external instructions or the working parameters set according to the built-in parameters, and controls the radar to enter the working mode.

[0081] Under the influence of the modulated pulse (excitation signal) generated by the signal processing module, the signal transmission unit transmits the frequency-modulated signal or phase-coded signal required for radar target detection. After being up-converted to the radar operating band in the signal transmission unit, it undergoes power amplification and is then radiated by the dual-polarization phased array antenna. The transmitted excitation signal is in the form of an electromagnetic wave. After encountering the target, the electromagnetic wave is backscattered to form an echo signal. The digital receiving unit in the dual-polarization phased array antenna receives the returned echo signal. After low-noise amplification, filtering, down-conversion to a digital intermediate frequency, and AD sampling in the digital transceiver module 4, it is transmitted to the multi-channel DBF module. The DBF module forms a receive beam signal, and then the signal processing module performs spectrum analysis to obtain target echo information. Finally, the echo information is transmitted to the designated location (which can be a remote terminal) by the communication module.

[0082] The weather radar provided by the present invention utilizes a pulse compression system to balance range resolution and effective range. The excitation signal waveforms utilize linear frequency modulation (LFM), nonlinear frequency modulation (NFM), and phase-coded pulses. Its bandwidth is 5 MHz, achieving a range resolution of 30 meters, and its pulse width is adjustable from 0.5 μs to 200 μs. After pulse compression, frequency-domain weighting is used in the signal processing module to reduce range sidelobes.

[0083] When the dual-polarization phased array antenna provided by the present invention is used for signal transmission, in order to ensure the maximum possible radiation of electromagnetic waves, amplitude and phase weighting is not used to reduce side lobes, such as Figure 6 When receiving, in order to achieve a maximum sidelobe level of ≤-30dB or lower, it is necessary to use amplitude and phase weighting to reduce the sidelobe, such as Figure 7 shown.

[0084] Compared with existing planar phased array weather radars, the dual-polarization phased array weather radar provided by the present invention, which includes a transverse cylindrical dual-polarization phased array antenna, has the following advantages:

[0085] 1. The use of bipolar line feed can improve the beam scanning performance of phased array weather radar, achieve digital multi-beam with constant beam width, constant antenna gain, and constant dual-polarization performance, ensure the consistency of weather detection at different scanning angles, and improve the accuracy of constructing three-dimensional weather targets.

[0086] 2. By controlling the opening and closing area of ​​the bipolar line feed, the electronic scanning capability of -2° to 182° can be achieved, further shortening the full airspace detection time of the phased array weather radar and improving the ability of the phased array weather radar to identify particle phases and weather characteristics.

[0087] 3. The use of a horizontal cylindrical dual-polarization phased array antenna simplifies the calibration requirements of the phased array weather radar, improves the radar's usability and adaptability, and facilitates the expansion and upgrade of the radar and its application scope.

[0088] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0089] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A dual-polarization phased array weather radar, characterized in that: include: Information processing module and dual-polarization phased array antenna; The dual-polarization phased array antenna includes: a transverse cylindrical support surface, a support frame and multiple dual-polarization line feeds; The support frame is matched with the transverse cylindrical support surface; the support frame is used to support the transverse cylindrical support surface; A plurality of the dual-polarized line feeds are arranged on the transverse cylindrical support surface, and the plurality of the dual-polarized line feeds are closely arranged along the circumferential direction of the transverse cylindrical support surface; each of the dual-polarized line feeds includes a plurality of line feed inner sub-arrays; each of the line feed inner sub-arrays includes an electronic switch and a plurality of antenna radiating units; The electronic switch is connected to the antenna radiating unit; the electronic switch is used to turn on and off the antenna radiating unit; the horizontal polarization and vertical polarization transmission waveforms adopt orthogonal coding form; The information processing module is connected to the dual-polarization phased array antenna; the information processing module is used to perform spectrum analysis based on the signal received by the dual-polarization phased array antenna to obtain target echo information; the information processing module is also used to generate control instructions to drive the dual-polarization phased array antenna to perform signal acquisition in the horizontal direction and / or signal acquisition in the pitch direction; when the dual-polarization phased array antenna transmits signals, amplitude and phase weighting is not used to reduce side lobes; when receiving signals, amplitude and phase weighting is used to reduce side lobes.

2. The dual-polarization phased array weather radar according to claim 1, characterized in that: The information processing module is connected to the electronic switch in the dual-polarization phased array antenna; the information processing module is used to control the opening and closing of the electronic switch, and the dual-polarization phased array antenna forms electronic scanning at different angles in the pitch direction according to the area where the electronic switch is turned on.

3. The dual-polarization phased array weather radar according to claim 1, characterized in that: The information processing module includes: a multi-channel DBF module, a signal processing module and a communication module; The multi-channel DBF module is connected to the signal processing module; the signal processing module is connected to the communication module; The multi-channel DBF module is used to convert the echo signal received by the dual-polarization phased array antenna into a beam signal; the signal processing module is used to obtain target echo information after performing spectrum analysis on the beam signal; and the communication module is used to send the target echo information.

4. The dual-polarization phased array weather radar according to claim 1, characterized in that: The dual-polarization phased array antenna also includes: a digital transceiver module; The digital transceiver module includes a plurality of dual-channel digital T / R components; Each of the dual-polarization line feeds corresponds to one of the dual-channel digital T / R components; the dual-channel digital T / R component is used for transmitting and receiving signals.

5. The dual-polarization phased array weather radar according to claim 4, characterized in that: The dual-channel digital T / R assembly includes a digital receiving unit and a digital transmitting unit; The digital transmitting unit is used to generate a frequency modulation signal or a phase coding signal required for detecting a target; and the digital receiving unit is used to receive an echo signal reflected back by the target.

6. The dual-polarization phased array weather radar according to claim 5, characterized in that: The digital transmitting unit is a fully solid-state transmitter.

7. The dual-polarization phased array weather radar according to claim 1, characterized in that: The dual-polarization phased array antenna further includes: a driving module; The driving module is connected to the supporting frame to drive the supporting frame to rotate horizontally.

8. The dual-polarization phased array weather radar according to claim 7, characterized in that: The driving module includes: a driving motor, an angle encoder and a motor control unit; The angle encoder and the drive motor are both connected to the motor control unit; The motor control unit is used to control the driving motor to drive the support frame to rotate to a specified angle according to the angle information in the angle encoder.

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