Terahertz ISAR three-dimensional imaging method based on backward projection

Abstract

The invention relates to a terahertz ISAR three-dimensional imaging method based on backward projection. The method comprises the following steps of S1 forming an orthogonal base line structure by four antennas arranged in the same plane, wherein the four antennas comprises a transmitting antenna O and receiving antennas A, B, C; S2 calculating a reference distance; S3 carrying out Dechirp processing and pulse compression processing on the echo signal; S4 calculating the distance resolution and azimuth resolution of the target; S5 calculating the slope distance of the sampling points in each imaging space at each azimuth moment to each receiving antenna; S6 carrying out phase compensation on the receiving antennas A, B, C to obtain a BP imaging result; S7 extracting a strong scattering point for the BP imaging result; S8 extracting the interference phase of the strong scattering point; and S9 back calculating a three-dimensional coordinate of each scattering point in the three-dimensional space to obtain a three-dimensional imaging result. The method can effectively improve the fine recognition and interpretation capability of unknown non-cooperative targets.

Description

technical field [0001] The invention relates to a three-dimensional imaging method, specifically a back-projection interference three-dimensional imaging method for non-cooperative targets of inverse synthetic aperture radar (ISAR) in the terahertz band, and belongs to the technical field of radar signal processing. Background technique [0002] In recent years, with the development of advanced military equipment such as stealth fighters (F-22, F-35, etc.), near-space vehicles (CAV, HTV-2, etc.) With rapid development, air / space incoming targets are gradually possessing combat performances such as high speed, high maneuverability, small size, strong defense penetration, and strong stealth. This poses a huge challenge to my country's existing detection and early warning methods. [0003] Modern stealth technology, whether it is shape stealth, radar absorbing material stealth, or even plasma stealth, is mainly designed for microwave radar below 40GHz. At present, the commonly ...

AI Technical Summary

Problems solved by technology

In synthetic aperture radar applications, the path is known, so it is more commonly used, however, in ISAR imaging, because the integrated path of the target is unknown, a new solution needs to be proposed

Interferometric SAR imaging using BP imaging has been studied by some scholars, but there are currently few terahertz radar systems and interferometric ISAR imaging systems in China. Terahertz 3D ISAR imaging based on BP algorithm has important research significance and practicality for fine target recognition. Value

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