Microwave Photon Distributed Radar Imaging System and Method

Abstract

A distributed radar imaging system, comprising: a central station, which modulates n channels of optical carriers of different wavelengths with low-frequency narrow-band chirp electrical signals, and transmits them to a transmitting station and (n-1) receiving stations through optical fibers with different delays respectively, Perform beam combination and parallel deskewing processing on the echo optical signals from the receiving station, and perform analog-to-digital conversion, transmission phase delay compensation, frequency domain segmentation and three-dimensional imaging processing on the combined beam and deskewing signals; The optical radio frequency signal is converted into a high-frequency broadband linear frequency modulation electrical signal for transmission; the receiving station receives the target echo signal, modulates the optical radio frequency signal from the central station, and transmits it back to the central station through optical fiber. The invention also discloses a microwave photon distributed radar imaging method. The invention applies photon frequency doubling, optical fiber radio frequency transmission and photon parallel deskewing processing technology to distributed radar, realizes three-dimensional imaging under the architecture of one transmission and multiple reception, reduces system complexity, and improves system distribution capability and imaging performance.

Description

technical field [0001] The invention relates to the field of radar imaging, in particular to a microwave photon distributed radar imaging system and method. Background technique [0002] Microwave radar has all-weather, all-weather, high-resolution remote sensing imaging capabilities, and plays an indispensable and important role in land mapping, resource survey, environmental disaster monitoring, regional reconnaissance and other fields. With the development of science and technology and the promotion of applications, modern radars are developing in the direction of high resolution, multi-function, miniaturization, and reconfiguration. However, limited by the "electronic bottleneck", it is difficult for electronic technology to realize the generation, control and processing of broadband signals, which brings great challenges to the realization of multi-band broadband reconfiguration of traditional radars. In recent years, photonic technology has become a "key technology to...

AI Technical Summary

Problems solved by technology

The problems with this method are: (1) It is difficult to distinguish multiple main scatter points located in the same range-Doppler unit, and there is no geometric resolution in the third dimension; (2) The measurement accuracy of the third dimension increases with the increase of the baseline , but the quality of phase interference also decreases, and there is a contradiction between the two

However, the increased number of transmitters and receivers will exponentially increase system cost and complexity

In addition, the increase of the baseline also brings new challenges to signal coherent processing. In the existing multi-base electronic radar, after the receiver receives the echo signal of the target, it needs to be pre-processed locally, and then sent back to the central site for further processing. Data fusion, so it is difficult to avoid the loss of some information

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