Single and dual multi-dwell synchronization for a direct-sequence spread spectrum receiver

This paper investigates factors affecting the coarse synchronization performance of a multi-dwell circuit for direct sequence spread spectrum receivers. The influence of the search/verification/lock (SVL) strategy, detector threshold and dwell time on the speed of acquisition is analyzed. For a selected multi-dwell SVL strategy, the mean, variance and distribution of the acquisition time are presented for several values of the detector threshold. A system design example is presented which demonstrates the high sensitivity to detector threshold. Two dual multi-dwell circuits that reduce the acquisition time are presented. The first approach searches two mutually exclusive areas, while the other searches the full region in opposite directions. It is shown that there is little difference in performance between these dual multi-dwell circuits.