Study on Complexity-Reduced Iterative Equalization Algorithm for Mobile OFDM

In high mobility Orthogonal-frequency division multiplexing (OFDM) systems, time-varying channels destroy the orthogonality among subcarriers and theresultant Intercarrier interference (ICI) degrades the receiver performance. To obtain an effective balance of performance and complexity at the receiver, we proposed tosplit the Channel frequency response (CFR) matrix into asequence of submatrices rather than using the whole CFRmatrix. Then, we derived a soft information based sequentially iterative Minimum mean square error (MMSE)equalizer, which fully exploits the ICI distribution property. Analysis and simulations demonstrate that thisscheme provides a flexible and controllable approach totrade off performance for complexity, since it can be simplydone by choosing different size of the parameter Q. Meanwhile, superior ability of the ICI suppression is maintainedwhen compared with previous equalization schemes. Thisfeature indicates its potential application for future wireless communications.