Design and implementation of a channel simulator for wideband mobile radio transmission

The authors present the practical design and implementation of a channel simulator for wideband (up to 10 MHz) mobile radio transmissions. The simulator is intended to be used for laboratory tests on high-bit-rate and spread-spectrum transmissions. Rician and Rayleigh frequency-selective fading is simulated by feeding four flat Rayleigh-fading simulator branches through the different taps of a SAW (surface-acoustic-wave) delay line. A digital signal processor is used for the generation and filtering of the random signals from which fading is simulated, with independently selectable Doppler filter cutoff frequencies in each branch. The authors present comparisons between the simulator´s output and simulation results. These comparisons illustrate the static channel frequency response, with frequency-selective fading depths of up to 35 dB, and the coherence bandwidth property of the channel