Blind Demodulation of Chaotic Direct Sequence Spread Spectrum Signals Based on Particle Filters

Entropy

Ting Li¹  Dexin Zhao²  Zhiping Huang²  Chunwu Liu²  Shaojing Su² 

[1] College of Mechatronics Engineering and Automation, National University of Defense Technology, Deya Road, Changsha 410073, China;

关键词: blind demodulation;    chaotic direct sequence spread spectrum;    particle filter;    colored non-Gaussian noise;   

DOI  :  10.3390/e15093877

来源: mdpi

【 摘 要 】

Applying the particle filter (PF) technique, this paper proposes a PF-based algorithm to blindly demodulate the chaotic direct sequence spread spectrum (CDS-SS) signals under the colored or non-Gaussian noises condition. To implement this algorithm, the PFs are modified by (i) the colored or non-Gaussian noises are formulated by autoregressive moving average (ARMA) models, and then the parameters that model the noises are included in the state vector; (ii) the range-differentiating factor is imported into the intruder’s chaotic system equation. Since the range-differentiating factor is able to make the inevitable chaos fitting error advantageous based on the chaos fitting method, thus the CDS-SS signals can be demodulated according to the range of the estimated message. Simulations show that the proposed PF-based algorithm can obtain a good bit-error rate performance when extracting the original binary message from the CDS-SS signals without any knowledge of the transmitter’s chaotic map, or initial value, even when colored or non-Gaussian noises exist.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.