Precombining adaptive-order equalizer for downlink MAI suppression in CDMA systems

A new MAI suppression method - precombining adaptive-order equalizer - is proposed for a cellular CDMA system downlink. By means of increasing and smoothing the SNR variation of the input signal and optimizing the equalizer order, it greatly improves the performance of the common equalizer-based MAI suppression receivers in low SNR and fading cases. The proposed approach is especially suitable for 3G high-speed downlink packet access (HSDPA) systems. The receiver structure is described and represented mathematically. The receiver performance is evaluated through simulation and compared with common equalizer-based and RAKE receivers.