Patent ID: 7164706
Filing Date: 2007-01-16
Classification: H04B

Abstract:
1. A method of processing spread spectrum waveforms transmitted by a plurality of users of a spread spectrum system, comprising: computing a matrix representing cross correlations among the waveforms, said computing step including performing matrix calculation on at least a first one of two matrix components related by a symmetry property defined in accord with the relation: wherein computing a second one of the two matrix components as a function of the first matrix component by applying said symmetry property, and generating estimates of symbols transmitted by the users and encoded in said waveforms as a function of the cross correlation matrix wherein the step of computing the cross-correlation matrix comprises computing a matrix (herein referred to as Γ-matrix) that represents correlations among short code sequences associated with the respective users in accord with the relation: wherein c c N represents the length of the code, and N wherein the step of computing the cross-correlation matrix comprises computing a matrix (herein referred to as C matrix) representing cross-correlations among time lags associated with the transmitted waveforms and correlations among the short code sequences of the respective users as a function of the Γ-matrix in accord with the relation: wherein g is a pulse shape vector, N τ is a time lag, m is a symbol period, and Γ represents the aforesaid Γ matrix.