Using a direct conversion receiver in EDGE terminals-a new DC offset compensation algorithm

The basic concept of EDGE (Enhanced Data rates for GSM and TDMA/136 evolution) is to provide higher data rate transmission, over 384 kbits/s, than in the GSM and TDMA/136 systems of today. In order to be able to reach such a high data rate within the GSM bandwidth a very good receiver design is required. Further, from a terminal perspective, the receiver design needs to be efficient from both a cost, current and size point of view. A direct conversion receiver fulfil these criteria. However, such an architecture gives rise to a DC offset that must be taken care of in order for good demodulation. A DC offset compensation algorithm based on joint estimation of the radio channel and the DC offset is presented, giving competitive receiver performance for the EDGE system.