Weak Signal Acquisition in Satellite Positioning

Abstract

This thesis discusses the acquisition of Global Navigation Satellite System (GNSS) signals that are attenuated in propagation and proposes a receiver independent method of characterizing the acquisition performance of the signals. It then applies the proposed method to several GNSS signals with different assumptions about available acquisition assistance. Two receiver improvements are proposed, one to increase success rate in parallel acquisition and another to enhance sensitivity in serial acquisition. In the remaining part of the thesis, two techniques are presented for making satellite signals easier to acquire, one involving a novel family of ranging sequences and another involving a special symbol sequence for transmitting time information over a heavily attenuating propagation channel.