Novel Algorithm for Blind Estimation of Scramblers in DSSS Systems

Abstract

In this paper, we propose a novel algorithm for blind estimation of a linear scrambler, which is a synchronous scrambler or a self-synchronous scrambler, in direct sequence spread spectrum systems and analyze its estimation performance. We first examine the statistics considering the linearity of the scrambled data and the repetition property of the spreading code. Based on this, we then propose an improved estimation algorithm for the feedback polynomial of the linear scrambler constituting a search process and a verification process of feedback polynomial candidates to determine the correct feedback polynomial of the scrambler. To validate the proposed algorithm, we show through computer simulations that the proposed algorithm outperforms the conventional algorithm in terms of estimation performance.