A Method for Estimating Chirp Rate of a Linear Frequency Modulated Signal

Abstract

This paper proposes a fast and accurate chirp-rate estimation algorithm in noisy environment. The proposed method searches the inverse maximum magnitude of the angle-sweep fractional Fourier domain and finds the optimum angle, which provides an estimate for the chirp-rate. In order to accelerate the search process, we propose to use the Fibonacci search algorithm, which provides a sub-optimal search scheme in terms of computational complexity. Simulation results show the efficiency of the proposed algorithm. 

Keywords

• Fractional Fourier transform,chirp-rate,linear frequency modulated signals,estimation,Cramer-Rao lower bound

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