Iterative soft sequential estimation aided differential acquisition of m-sequences

Abstract

In this contribution a novel sequential estimation method is proposed for the acquisition of m-sequences. This sequential estimation method exploits the principle of iterative soft-in-soft-out (SISO) decoding for enhancing the acquisition performance, and that of differential pre-processing for the sake of achieving an enhanced acquisition performance, when communicating over various propagation environments. Hence the advocated acquisition arrangement is referred to as the differential recursive soft sequential estimation (DRSSE) acquisition scheme. The DRSSE acquisition scheme exhibits a low complexity, which is similar to that of an m-sequence generator, while achieving an acquisition time that is linearly dependent on the number of stages in the m-sequence generator. Owing to these attractive characteristics, the DRSSE acquisition scheme constitutes a promising initial synchronization scheme, in particular, when acquiring long m-sequences transmitted over various propagation environments.