Jamming interference suppression and multiuser detection for DSSS systems in time-frequency selective channels

In this paper, we propose a receiver structure that reduces multiple degradation on the transmitted signal in time-frequency selective direct sequence spread spectrum systems. The structure incorporates time-frequency diversity within a minimum mean square estimation technique based on orthonormal projections. It also uses time-varying signal processing techniques to mitigate additive wideband jamming interference. Simulations demonstrate that the simpler structure of our multiuser detector is efficient and the overall combined system is robust to multipath and Doppler fading, and multiple access and jamming interference.