An Interpolation-Based Approach to Time-Varying Equalizer Design
Communications over time-varying channels entail receiver designs which adapt themselves to the channel temporal variations and consequently pose significant computational requirements for the receiver. This work studies the equalization of such channels from the perspective of the computational complexities involved and proposes a flexible, low-complexity scheme for the design of time-varying equalizers based on reconstructing the time-varying equalizer from its samples through a combination of the Fourier exponentials and the Gradient Descent algorithm. This approach is considered for both linear and decision feedback equalizer designs. It is further extended to the framework of turbo equalization for time-varying channels. Numerical simulations have been performed to evaluate the performance of this proposed scheme, while a detailed complexity analysis shows that the proposed scheme can result in significant simplification in the receiver design complexity without incurring much performance loss.
KeywordsTime-varying Low complexity Equalization Doubly selective channels Gradient descent
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