A low complexity EDGE demodulator based on FDE and impulse response shortening

In this paper, a new low-complexity frequency-domain based technique is proposed for channel equalization and symbol detection of an Enhanced Data Rate for Global Evolution (EDGE) cellular system, which uses 8-PSK modulation. The proposed method exploits the present of tail symbols in the EDGE slot structure and uses them as partial Cyclic Prefix in the frequency domain equalizer. For channels with longer memory than the tail length, the receiver computes a channel shortening filter such that, when the filter is cascaded with receive chain, results in a shorter effective impulse response. The parameters of the channel shortening are set such that the effective impulse response memory length is equal to the tail length. The performance of the proposed system is demonstrated by computer simulations.