On Interference Suppression in Doubly-Dispersive Channels with Hybrid Single-Multi Carrier Modulation and an MMSE Iterative Equalizer

In this letter, we propose a scheme to suppress the interference involved in doubly-dispersive channels with large Doppler shift. The scheme employs a minimal mean square error (MMSE) iterative equalization together with a hybrid single-multi carrier (HC) modulation based on weighted-type fractional Fourier transform (WFRFT). The residual large interference is suppressed more effectively in HC systems after a linear MMSE equalization with prior information obtained from the log-likelihood ratio. And simulation results indicate that HC with the iterative equalization outperforms orthogonal frequency division multiplexing and single carrier with methods of iterative equalization formerly proposed in terms of the bit error rate performance.