Optimization of Orthogonal Polyphase Spreading Sequences for Wireless Data Applications

Authors

B. J. Wysocki, University of Nebraska-LincolnFollow
Tadeusz Wysocki, University of Nebraska-LincolnFollow

Date of this Version

2001

Comments

Published in Vehicular Technology Conference, 2001. VTC 2001 Fall. IEEE VTS 54th Volume 3, 7-11 Oct. 2001 Page(s):1894 - 1898 vol.3 Digital Object Identifier 10.1109/VTC.2001.956530 Copyright 2001 IEEE. Used by permission.

Abstract

In this paper, we propose a simple but efficient method for optimizing correlation properties of polyphase spreading sequences for asynchronous DS CDMA applications. The proposed method can be used to minimize the mean square value of aperiodic crosscorrelation or the mean square value of aperiodic autocorrelation, the maximum value of aperiodic crosscorrelation functions, merit factor or other properties of the sequence set. The important feature of the method is that when applied to orthogonal sequences, it modifies correlation properties of the sequence set, while preserves their orthogonality for perfect synchronization.