Rapid converging adaptive interference suppression for direct-sequence code-division multiple-access systems

Rapid converging adaptive equalization algorithms for interference suppression in direct sequence code division multiple access (DS/CDMA) systems are presented. These adaptive algorithms, based on an orthogonal transformation, do not require a priori knowledge on interfering signals parameters such as spreading sequences and relative signal power levels. The convergent rate of these algorithms is independent of the eigen-value spread of the input data correlation matrix. The performance of these proposed rapid converging adaptive equalizers is investigated both in the absence and presence of frequency offsets among transmitters