Committee: 

Dr. Barry, Advisor

Dr. Lanterman, Chair

Dr. Li

Abstract:

The objective of the proposed research is to develop receiver signal processing strategies for reliable detection and demodulation of direct-sequence spread spectrum (DSSS) signals, despite a multipath channel with low SNR, high Doppler frequencies, time-varying delays, and jamming. In particular, we will investigate algorithms for detecting the presence of a long-code DSSS signal below the noise floor, without any prior knowledge of its spreading code.   Furthermore, we will also develop signal processing strategies for estimating the time-varying delays and Doppler frequencies for each path, so that we can reliably recover information from a DSSS transmission whose spreading code is either known or has been estimated. Finally, we will devise strategies for ensuring that the receiver is robust to jamming.