Blind adaptive reduced-rank CDMA receivers based on interpolated FIR filters with adaptive interpolators in multipath channels

Blind adaptive reduced-rank receivers based on interpolated finite impulse response (FIR) filters with adaptive interpolators for direct sequence code division multiple access (DS-CDMA) systems are proposed and examined in multipath channels. The interpolated constrained minimum variance (CMV) solutions for both receiver and interpolator are described for mitigating multiple access interference (MAI) and multiple-path propagation effects in a downlink scenario. Computationally efficient blind adaptive algorithms for both receiver and interpolator based upon the minimum variance (MV) performance criterion are then developed with appropriate constraints to mitigate MAI, intersymbol interference (ISI) and jointly estimate the channel.