Adaptive TDMA-DFE algorithms under IS-136

The IS-136 standards define conditions under which wireless TDMA systems are required to work. Adaptive equalizers are unavoidable in order to satisfy these requirements. We extend common results in tracking theory for system identification to the equalization case. Unlike in system identification where a steady-state error energy is minimized, the optimization criterion here is the minimum of the BER. However, we show that both are related by a monotone function and therefore minimizing the BER is equivalent to minimizing the steady-state-error energy. Optimum parameters for LMS as well as RLS algorithms are derived and simulation results indicate that under the conditions defined in the IS-136 standards, the performance of the two methods is comparable.