Adjacent channel interference suppression in FDMA/TDMA mobile radio systems using joint demodulation

The capacity and signal duality of wireless communications systems can be improved by enhancing receiver performance in the presence of adjacent channel interference (ACI). In this paper, an MLSE receiver for joint demodulation of adjacent channel signals is developed. This receiver provides significant improvement in performance over a wide range of carrier to interference ratios. A practical approach is taken, in which conventional down-conversion of each signal is performed followed by joint demodulation at baseband. To provide coherent reception, a novel form of joint channel estimation is used, exploiting knowledge of the transmit and receive filter responses. Receiver performance is evaluated via simulation for the GSM digital cellular system