Resolving sub-chip spaced multipath components in CDMA communication systems

A method is developed for resolving channel multipath components in direct-sequence code division multiple access (DS-CDMA) communications. Components spaced closer than a chip interval of a sequence are separable by the technique. The method is based on the constrained iterative deconvolution using the method of projection onto convex sets (POCS). A new POCS constraint is derived which utilizes the noise covariance modified by a matched filter. Simulation results for m-sequences and binary phase shift keying (BPSK) modulation are presented.