Fast Adaptive Algorithms for Updating Variable Length Equalizer Based on Exponential

Adaptive linear equalizers are commonly used in wireless systems to reduce the distorting effects of the channel. One of the key parameters to be determined is the length of the equalizer. In a time varying scenario, the optimum length may vary as a result of changes in the environment. Two fast convergence adaptive length updating algorithms based on exponential function are proposed to regulate the length of the equalizer according to the instantaneous channel conditions. Simulation results show that the algorithms can track even a very fast changing channel.

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