Efficient equalization of nonlinear communication channels

Nonlinear intersymbol interference (ISI) often arises in voice-band communication channels at high transmission rates or in satellite channels due to nonlinearities in power amplifiers. The proposed equalizers for the cancellation of the nonlinear interference are mainly based on the Volterra series expansion, which is an elegant but very complex model. This paper presents a decision feedback equalizer (DFE) which is based on a new nonlinear filter structure. It is composed only of linear taped delay line filters and multipliers. Hence, the complexity of this still very general structure is comparable to linear filtering. Simulation of data transmission over a telephone channel show that the proposed DFE clearly outperforms the conventional DFE and is also superior to the Volterra DFE with a comparable complexity