Fast initialization of equalizers for VSB-based DTV systems in multipath channel

Abstract

This paper proposes a fast initialization technique for equalization of 8-VSB based digital television (DTV) signal in severe multipath channels. We consider the use of a modified decision feedback equalizer (MDFE) for fast initialization. The feedback filter (FBF) of the MDFE can be initialized simply by estimating the channel impulse response and only the feedforward filter (FFF) of the MDFE needs training for initialization. To overcome the shortage of the training sequence in the VSB DTV signal, we propose a new initialization method by generating a virtual training signal to initialize the FFF of the MDFE. Simulation results show that the proposed scheme can quickly initialize the equalizer using less than 5000 symbols, while providing a receiver performance comparable to that of conventional schemes.