Performance Comparison of Linear and Decision Feedback Equalizers in Flat and Frequency Selective Fading Channel

Abstract — In this paper we have studied channel models (flat fading and frequency selective fading channels) estimation, adaptive equalization, and demodulation. The technique involves the optimization of the overall impulse response of the transmit and receive filters and effectively reduces the channel to one which is flat fading. This example showed the relative performance of linear and decision feedback equalizers in both frequency-flat and frequency-selective fading channels. It showed how a one-tap equalizer is sufficient to compensate for a frequency-flat channel, but that a frequency-selective channel requires an equalizer with multiple taps. Finally, it showed that a decision feedback equalizer is superior to a linear equalizer in a frequency-selective channel. Computer simulation results show that this equalization method works for channels with small delay spread