Design of partially adaptive STBC CDMA receiver using conjugate gradient algorithm

A novel partially adaptive (PA) receiver with MAI suppression is proposed for an STBC CDMA system under the multipath fading channels. A low-complexity PA realization of the receiver is developed based on the generalized sidelobe canceller (GSC) technique which partial adaptivity is incorporated via the conjugate gradient (CG) algorithm for reduced complexity implementation. The proposed PA receiver is evaluated through simulations, and the results show that it can achieve nearly the same performance of the conventional fully adaptive MMSE receiver by using a small number of pilot symbols.