Single Antenna Interference Cancellation using Prefiltering and Multiuser Joint Detection based on the M-Algorithm

Cellular mobile radio systems like GSM/EDGE (Enhanced Data Rates for GSM Evolution) using pulse amplitude modulation (PAM) for transmission over frequency-selective channels are confronted with increasing demands on spectral efficiency. By using advanced signal processing techniques, receivers are able to cope with higher interference power levels from e.g. cochannel cells, therefore allowing a smaller frequency reuse. In mobile phones, only a single antenna can be applied. We assume 8–ary phase–shift keying (8PSK) modulation and consider a joint detection approach for single antenna receivers in the downlink using the M-algorithm and a novel prefiltering approach. The dominant interferer signal is treated together with the desired user signal by joint detection in order to increase robustness to cochannel or adjacent channel interference. Simulations exhibit high performance gains compared to conventional receiver techniques.