Maneuvering target parameter estimation method by combining correction RFT (Radon-Fourier Transform) and MDCFT (Modified Discrete Chirp-Fourier Transform)

Abstract

The invention discloses a maneuvering target parameter estimation method by combining correction RFT (Radon-Fourier Transform) and MDCFT (Modified Discrete Chirp-Fourier Transform). According to the method, a method for searching target echo data through the RFT is improved by using a previously known parameter range for movement of a maneuvering target, so the target echo data with a range curve can be taken out, corresponding matching processing is performed on the basis of the taken echo data, and further estimated values of initial speed and acceleration of the target are obtained. According to the method, a better maneuvering target parameter estimation result can be obtained under the conditions of limited radar pulse accumulation pulse number and low signal-noise ratio. According to the method, the target speed estimation result is compared with estimation results of MTD (Moving Target Detection), RFT, fractional fourier transform and Radon-fractional fourier transform methods; besides, the estimation result of the target acceleration by the method is compared with the estimation results of the fractional fourier transform and the Radon-fractional fourier transform methods, and the experimental result proves the effectiveness of the method.

Description

technical field [0001] The invention belongs to the technical field of radar signal processing and maneuvering target parameter estimation, in particular to a maneuvering target parameter estimation method combining modified RFT and MDCFT. Background technique [0002] The United States first proposed that completing the control of space as soon as possible is the highest priority task at present, and this task needs to be realized with the help of space-based early warning radar. Different from the limited effective coverage of ground-based radar and its limited ability to detect long-distance targets, space-based early warning radar is distributed in the orbital range that needs to be observed, and has the characteristics of wide observation range and strong wartime capability. And because the space-based early warning radar was only proposed in recent years to observe the target, and the technology is still in a relatively rapid development stage, it is of great significa...

AI Technical Summary

Problems solved by technology

The envelope shift compensation method shifts the echo signal in the time domain, moves the echo signal that generates distance walking into a range unit, and then performs FFT along the slow time domain, so that the target speed can be estimated. However, the displacement compensation effect of this method is affected when the signal-to-noise ratio is low, so the speed estimation accuracy is limited to a certain extent.

The minimum entropy method also cannot obtain a good envelope alignment effect in the case of low signal-to-noise ratio, which will also affect the accuracy of speed estimation

The shuttle transform method corrects the echo signal into a range unit by performing sinc interpolation in the time domain of the signal, but the calculation amount will increase rapidly with the increase of the echo data matrix

In 2011, Xu Jia et al. proposed the Radon-Fourier Transform (RFT) method, which performs Fourier transform along the trajectory of the target in the range gate-slow time domain, so as to accumulate the energy of the target and estimate the The speed of the target, but the speed estimation accuracy of this method will be affected to a certain extent when the target has acceleration

Although the MDCFT method overcomes the limitations of the conventional DCFT method on sampling points and frequency modulation parameters, the method has the problem of central frequency ambiguity

[0007] At present, there are no relevant research results on the maneuvering target parameter estimation technology that combines the modified RFT and MDCFT

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