Equalisation for EDGE mobile communications

An equalisation concept for the novel radio access scheme enhanced data rates for GSM evolution (EDGE) is proposed, by which high performance can be obtained at moderate computational complexity. Because high-level modulation is employed in EDGE, optimum equalisation as performed in most GSM receivers is too complex, and suboptimum schemes have to be considered. It is shown that delayed decision-feedback sequence estimation (DDFSE) is a promising candidate. For various channel profiles, approximations for the bit error rate of DDFSE are given and compared with simulation results. It turns out that a discrete-time allpass prefilter creating a minimum-phase overall impulse response is indispensable for obtaining a favourable tradeoff between performance and complexity. Additionally, the influence of the receiver input filter is investigated