Modified Wiener beamforming for indoor multipath channels

The impulse response of an indoor channel varies for different environments and spatial positions of a transceiver pair as a function of the phase relationship among individual multipath components that have a variety of time delays. These cause fading especially within chip durations of DS-CDMA systems. We propose modified Wiener beamforming (MWB) to co-phase the multipath components then combine them using maximum ratio combining within a chip duration. We derive formulas for MWB with a method to separate and estimate multipath vectors through each chip. We aim to isolate and recombine multipath components before they add together as a phasor to generate fading. Therefore the fading of Rayleigh or Rician distributed multipath within each chip duration can be reduced to a minimum. Simulation results are presented by using a three dimensional ray tracing to support the proposed method.