DS spread spectrum signal acquisition using adaptive threshold techniques
Waseem W. S. Jibrail · International Journal of Communication Systems · 1998
Initial synchronization (i.e. acquisition) of the spreading wave-form is a significant problem in spread spectrum system design. In this paper, adaptive threshold techniques are employed in a serial search acquisition scheme for direct sequence (DS) spread spectrum signals to improve the mean acquisition time of the system. Two approaches for adpative threshold modelling are presented, analysed and compared, namely the sample test approach and the probability-of-error approach. The results show that, using an adaptive threshold, a significant improvement may be achieved in the mean acquisition time for a certain range of interference-to-signal ratios (ISRS). The type of interference assumed is narrowband interference, from which DS spread spectrum systems suffer most, in addition to additive white Gaussian noise (AWGN). © 1998 John Wiley & Sons, Ltd.