Modulation Parameter Estimation of LFM Interference for Direct Sequence Spread Spectrum Communication System in Alpha-Stable Noise

The linear frequency modulation (LFM) interference is one of the typical broadband interferences in direct sequence spread spectrum (DSSS) communication system. In this article, a novel parameter estimation method LFM proposed for DSSS system alpha-stable noise. To accurately estimate parameters, noise should be eliminated first. Thus, we formulate new generalized extended chirplet transform to suppress noise, robust time-frequency, transformation realized. Then, using Radon transform, maximum value after and chirp rate according angle related are estimated. addition, Fourier introduced initial interference. For performance analysis, Cramér-Rao lower bounds estimated presence derived. Moreover, asymptotic properties estimator analyzed. Simulation results demonstrate that significantly outperforms existing methods, especially low SNR regime.