Direct semi-blind design of serial linear equalizers for doubly-selective channels

Recently, serial linear equalizers (SLEs) and serial decision feedback equalizers (SDFEs) have been proposed to mitigate doubly-selective channel effects. To design the SLE/SDFE and to model the doubly-selective channel, a so-called finite impulse response basis expansion model (FIR-BEM) is used. Initially, the FIR-BEM coefficients of the SLE/SDFE were designed based on the exact knowledge of the FIR-BEM coefficients of the doubly-selective channel. In practice, we can use a direct SLE/SDFE design procedure, which avoids an intermediate channel estimation step. In this paper, we describe this idea for the SLE and focus on direct semi-blind design of the FIR-BEM coefficients of the SLE. Simulation results demonstrate the validity of the proposed approach.