Hypersonic speed target detecting method for polynomial Radon-polynomial Fourier transform

Abstract

The invention relates to a hypersonic speed target detecting method for polynomial Radon-polynomial Fourier transform, and belongs to the technical field of radar signal processing and detecting. The method comprises the steps that N periodic signals to be accumulated are sampled, a slow time-fast time target observed value is extracted, and pulse compression is performed on the sampled signals separately; initialization parameters of polynomial Radon-polynomial Fourier transform are determined; search, compensation and accumulation are performed in a parameter space through polynomial Radon-polynomial Fourier transform to obtain a range-Doppler distribution diagram subjected to phase-coherent accumulation; constant false-alarm detection and target motion parameter estimation are performed on the range-Doppler distribution diagram. According to the method, model building is performed on target motion through polynomial, range walk and Doppler spread of the signals are compensated through parameter search of the polynomial, and therefore effective accumulation detection on a high-speed high-mobility target can be achieved under a low signal-to-noise ratio background; in addition, effective search on the multi-dimensional parameter space is achieved in a multi-resolution search mode, and therefore the search real-time performance is improved.

Description

technical field [0001] The invention belongs to the technical field of radar signal processing and detection, and is suitable for solving the problem of coherent accumulation of hypersonic maneuvering targets in adjacent space. Background technique [0002] Near-space hypersonic weapons are a new means of military strike. Its most notable features are ultra-high speed, large maneuverability, and ultra-long range. Its flight speed can reach 5-25M, and its maneuvering overload can reach 10-20g. , large corners and many other irregular ways to achieve flight path maneuver avoidance and orbit change, can freely shuttle at high speed between outer space and tens of kilometers of adjacent space at an altitude of hundreds of kilometers from the ground, and can launch rapid attacks at extremely long distances . [0003] When a hypersonic vehicle moves near space, it will generate shock plasma, which will cause the target to have a certain degree of stealth. When a near-space vehic...

AI Technical Summary

Problems solved by technology

On the one hand, the hypersonic movement of adjacent space targets will appear the phenomenon of "cross-range gate", which limits the coherent accumulation time of radar signals

On the other hand, the Doppler frequency, Doppler change rate, and Doppler second-order change rate of the aircraft due to the strong maneuvering of the space target are much harsher than those faced by the previous ground-based radar detection system, resulting in "cross The "speed gate" phenomenon further affects the coherent accumulation of radar signals

[0005] At present, the methods to solve distance walking include frequency domain phase compensation method, Keystone transform method, generalized Keystone transform method, RadonFourierTransform (RFT) method, etc., and the methods to solve Doppler expansion include De-chirp method, fractional Fourier transform ( FRactionalFourierTransform, FRFT) method, polynomial phase method, etc. These methods are mainly aimed at traditional targets, such as aircraft, missiles, ships, etc., and the velocity and acceleration of hypersonic targets in the adjacent space are very large, which will lead to serious distortion of radar signals. Range walk and Doppler migration, and range walk and Doppler migration are mostly nonlinear, which severely limits the coherent accumulation of radar signals

At present, there are few coherent accumulation methods that can perform range nonlinear walking compensation and Doppler nonlinear migration compensation on hypersonic targets at the same time. Discovery capabilities of such targets

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