Vector channel modeling and prediction for the improvement of downlink received power

Many researchers have done significant work to reduce fast fading in single channel wireless systems using prediction. We introduce a novel synthesis and prediction filter at the smart antenna base station to predict the vector channel in time-division duplex systems. We show the advantage of modeling each component of the vector channel with the same coefficients over modeling each channel separately. Experimental results from measurements taken in downtown Austin show that prediction of the vector channel is feasible, even as far as ten steps ahead. Ray tracing simulations of downtown Austin, assuming noiseless line-of-sight and nonline-of-sight channels, show that these predictions enhance downlink beamforming resulting in improvements in downlink received power in excess of 10 dB in nonline-of-sight scenarios compared to beamforming without predictions. Furthermore, this improvement allows an increase in the duplex interval by more than three times, assuming constant mobile velocity.