CN-121978684-A - Full-polarization active phased array radar and signal processing method

CN121978684ACN 121978684 ACN121978684 ACN 121978684ACN-121978684-A

Abstract

The invention provides a full-polarization active phased array radar and a signal processing method, which belong to the technical field of radar signal processing, and comprise a radar cross dual-polarized antenna array, a dual-polarized transmitting channel, a dual-polarized receiving channel, a beam forming and synthesizing module and a signal processing control module, wherein the dual-polarized transmitting channel is used for generating and outputting two paths of radio frequency transmitting signals which are orthogonal in polarization mode and adjustable in phase difference, the dual-polarized receiving channel is used for receiving and processing dual-polarized echo signals from the cross dual-polarized antenna array, the beam forming and synthesizing module is used for carrying out airspace beam forming and polarization synthesizing processing on the dual-polarized echo signals, and the signal processing control module is used for sending control instructions to the dual-polarized transmitting channel and receiving polarization synthesized signals from the beam forming and synthesizing module to carry out target detection and identification. The invention improves the overall detection performance, the anti-interference capability and the target recognition accuracy of the radar in a complex electromagnetic environment.

Inventors

CUI HUAN
JING KAI

Assignees

航天南湖电子信息技术股份有限公司

Dates

Publication Date: 20260505
Application Date: 20251216

Claims (10)

1. The full-polarization active phased array radar is characterized by comprising a cross dual-polarized antenna array, a dual-polarized transmitting channel, a dual-polarized receiving channel, a beam forming and synthesizing module and a signal processing control module; The cross dual-polarized antenna array comprises a plurality of cross dual-polarized antenna units; the dual-polarized transmitting channel is connected with the cross dual-polarized antenna array and is used for generating and outputting radio-frequency transmitting signals with two paths of orthogonal polarization modes and adjustable phase difference between the two paths of radio-frequency transmitting signals; the dual-polarized receiving channel is connected with the cross dual-polarized antenna array and is used for receiving and processing dual-polarized echo signals from the cross dual-polarized antenna array; The beam forming and synthesizing module is connected to the dual-polarized receiving channel and is used for performing airspace beam forming and polarization synthesizing processing on the dual-polarized echo signals; the signal processing control module is connected to the dual-polarized transmission channel and the beam forming and synthesizing module, and is used for sending a control instruction to the dual-polarized transmission channel so as to set the phase difference of the two paths of radio frequency transmission signals, controlling the cross dual-polarized antenna array to radiate a transmission beam containing a specific polarization mode, and receiving the polarization synthesized signal from the beam forming and synthesizing module to detect and identify a target.
2. The fully polarized active phased array radar of claim 1, wherein the dual polarized transmit path comprises a digital T/R component and an analog T/R component; the digital T/R component is used for generating two paths of orthogonal polarization signals of a digital baseband according to the waveform control parameters and the amplitude-phase compensation data from the signal processing control module; The analog T/R component is connected between the digital T/R component and the cross dual-polarized antenna array and is used for carrying out up-conversion and power amplification on two paths of orthogonal polarized signals of the digital baseband to form the two paths of radio frequency transmitting signals.
3. The fully polarized active phased array radar of claim 1, further comprising a side lobe antenna, a side lobe receive processing channel; the side lobe antenna adopts a cross dual polarization design; the side lobe receiving and processing channel is connected with the side lobe antenna and the signal processing and controlling module and is used for receiving the interference signal and sending the processed interference signal to the signal processing and controlling module for polarization analysis, and the signal processing and controlling module generates the control instruction according to the polarization mode of the interference signal obtained by analysis.
4. The fully polarized active phased array radar of claim 1, wherein the beamforming and synthesis module comprises a digital beamformer; The digital beam former is used for weighting and synthesizing the multipath digital echo signals from the dual-polarized receiving channels to form a plurality of receiving beams in azimuth and elevation dimensions, wherein each receiving beam comprises two paths of orthogonal polarized signals, and polarization synthesis operation is carried out on the two paths of orthogonal polarized signals in each receiving beam.
5. The full-polarization active phased array radar according to claim 1, wherein the signal processing control module comprises a storage unit, and the storage unit pre-stores a target polarization characteristic library, wherein the target polarization characteristic library contains characteristic data of different types of targets in different polarization modes; and the signal processing control module acquires echo characteristics of the target in different polarization states by controlling the beam forming and synthesizing module to switch different polarization synthesizing modes, and performs matching identification with the target polarization characteristic library to obtain a target identification result.
6. A signal processing method of a fully polarized active phased array radar, applied to the fully polarized active phased array radar of any one of claims 1 to 5, comprising: generating a transmitting scheduling instruction according to the radar task demand; According to the transmission scheduling instruction, controlling the dual-polarized transmission channel to generate two paths of radio frequency excitation signals with orthogonal polarization modes and adjustable phase difference, and radiating a transmission beam containing a first polarization mode through a cross dual-polarized antenna array; Receiving a target echo signal through the cross dual-polarized antenna array; performing dual-polarized receiving and digital processing on the target echo signal to obtain dual-channel digital echo data; carrying out wave beam forming and polarization synthesis processing on the two-channel digital echo data to obtain a synthesized signal containing a second polarization mode; and detecting the synthesized signal, and estimating and identifying target parameters according to the detection result to obtain a target identification result.
7. The method for signal processing of a fully polarized active phased array radar of claim 6, wherein when the radar task requirement is anti-interference, the generating the transmit schedule command according to the radar task requirement comprises: receiving a space interference signal through a side lobe antenna, carrying out polarization analysis on the interference signal, and extracting a polarization mode in the interference signal as interference polarization information; And generating the transmission scheduling instruction according to the interference polarization information, wherein the transmission scheduling instruction comprises a phase difference control parameter for enabling the first polarization mode to be orthogonal with the interference polarization mode.
8. The method for signal processing of a fully polarized active phased array radar according to claim 6, wherein the performing beam forming and polarization synthesis processing on the two-channel digital echo data to obtain a synthesized signal including a second polarization mode includes: calculating signal quality measurement values of the two-channel digital echo data under different polar compound coefficients; Selecting a polarization synthesis coefficient corresponding to the maximum signal quality measurement value as a reference synthesis coefficient; And synthesizing the two-channel digital echo data by adopting the reference synthesis coefficient to obtain a synthesized signal containing a second polarization mode.
9. The method of signal processing for a fully polarized active phased array radar of claim 8, wherein the signal quality metric value is a signal to noise ratio or a signal to noise ratio.
10. The signal processing method of the full-polarization active phased array radar according to claim 6, wherein the performing target parameter estimation and identification according to the detection result to obtain a target identification result includes: Controlling the beam forming and synthesizing module to observe the same target area by adopting a plurality of different second polarization modes in sequence in the process of carrying out detection for a plurality of times by the radar, so as to obtain observation characteristics; Sequentially extracting micro-motion features or scattering features under each second polarization mode from the observation features to form multi-polarization feature vectors; and matching the multi-polarization feature vector with a pre-stored target polarization feature library, and determining a target type according to a matching result to serve as a target identification result.

Description

Full-polarization active phased array radar and signal processing method Technical Field The invention relates to the technical field of radar signal processing, in particular to a full-polarization active phased array radar and a signal processing method. Background With the rapid development of modern electronic countermeasure technology, the reconnaissance and analysis capability of countermeasure equipment such as an jammer on radar signals are obviously enhanced, the polarization state of radar radiation signals can be identified and copied by intercepting the radar radiation signals, and then targeted interference with the radar radiation signals is released, so that the normal detection performance of the radar is seriously weakened. In this context, polarization is increasingly gaining importance as a further key physical dimension of electromagnetic waves in addition to frequency, phase, amplitude, and its potential value in radar anti-interference, target enhancement detection, and feature recognition. Polarization techniques allow radars to improve their information acquisition capabilities in complex environments by selecting or matching particular electromagnetic wave polarization states, and traditionally, radars have attempted to suppress some of the interference or clutter by simple means such as polarization filtering. In the process of realizing the invention, the inventor realizes that the prior mode has at least the following problems that the prior mainstream early warning and monitoring radar, especially the widely applied active phased array radar, gradually exposes various inherent defects in practical application. Firstly, in terms of anti-interference, a fixed emission polarization mode is easy to be detected and imitated, and an interference machine can emit interference signals with the same polarization, so that the radar is difficult to effectively separate a target from interference from a polarization domain, and the accuracy of signal identification is low, and secondly, in terms of target detection, the radar scattering cross section (RCS) of the target is strongly dependent on the polarization mode of radar wave irradiation. When the radar is operated in a single fixed polarization mode, it may happen that the echo intensity of the target at that particular polarization is so weak that it is below the radar detection threshold, resulting in missed detection of the target. Finally, in the aspect of target identification and classification, a single polarization channel can only provide limited scattering information of a target in the polarization state, a complete and multidimensional polarization scattering matrix or polarization characteristics of the target cannot be obtained, and accuracy and reliability of fine classification and identification of the target based on the polarization domain characteristics are severely restricted. In summary, in the active phased array radar in the prior art, the technical problems of limited anti-interference capability, low probability of detecting the polarized sensitive weak and small targets, low accuracy caused by insufficient dimension of target identification features and the like generally exist, and the requirements on the comprehensive detection performance of the radar system in increasingly severe complex electromagnetic environments are difficult to meet. Disclosure of Invention In view of the foregoing, it is necessary to provide a full-polarization active phased array radar and a signal processing method, so as to solve the technical problems of limited anti-interference capability, low probability of detecting a polarization sensitive weak and small target, and low accuracy caused by insufficient dimension of target identification characteristics of the active phased array radar in the prior art. In order to solve the technical problems, in a first aspect, the invention provides a full-polarization active phased array radar, which comprises a cross dual-polarized antenna array, a dual-polarized transmitting channel, a dual-polarized receiving channel, a beam forming and synthesizing module and a signal processing control module; The cross dual-polarized antenna array comprises a plurality of cross dual-polarized antenna units; the dual-polarized transmitting channel is connected with the cross dual-polarized antenna array and is used for generating and outputting radio-frequency transmitting signals with two paths of orthogonal polarization modes and adjustable phase difference between the two paths of radio-frequency transmitting signals; the dual-polarized receiving channel is connected with the cross dual-polarized antenna array and is used for receiving and processing dual-polarized echo signals from the cross dual-polarized antenna array; The beam forming and synthesizing module is connected to the dual-polarized receiving channel and is used for performing airspace beam forming and polarization synthesizing proc