Rapid Acquisition in Direct-Sequence/Spread-Spectrum Systems

This book tackles the issue of the rapid acquisition of spreading codes in Direct-Sequence/Spread-Spectrum systems. In particular, a new algorithm is proposed that exploits the experience of the iterative decoding of modern codes to detect these sequences. This new method is a Message-Passing-based algorithm. Specifically, instead of correlating the received signal with local replicas of the transmitted Linear-Feedback-Shift-Register sequence, an iterative Message-Passing (MP) algorithm is implemented to be run on a loopy graph. Thus, this work is an analysis of the detection technique based on MP algorithms to acquire m-Sequences and Gold codes. In detail, an unified treatment to design and implement a specific set of graphical models for these codes is reported. A theoretical study on the acquisition time performance and the comparison to the standard algorithms is done. A preliminary architectural design is also provided. Finally, the analysis is also enriched by comparing this new technique to the standard algorithms in terms of computational complexity and (missed/wrong/correct) acquisition probabilities as derived by simulations.

Autorentext

F. Principe received the PhD grade in Information Engineering from the University of Pisa. He collaborated with INTECS SpA and LABEN SpA. He also spent 7 months at the Communication Sciences Institute USC, in Los Angeles. Currently, he works in IDS SpA. His research interests lie in the broad area of communication and satellite positioning systems.