Low-Complexity Iterative Hybrid Equalization for OSDM Systems

In this paper, we propose an iterative hybrid equalization algorithm, where our main aim is to provide a better solution towards the problem of high computational complexity during the transmission of Orthogonal Signal Division Multiplexing (OSDM) over underwater acoustics (UWA) channel. Our projected hybrid algorithm is a combination of block and least square QR (LSQR) equalization algorithms. Existing block equalization algorithm followed the iterative matrix inversion in doubly-selective channels, without the consideration of severe impairments in UWA channel. Thus, we added LSQR equalization along with this algorithm and offered a hybrid algorithm. LSQR exhibits compensation of UWA channel matrix inversions, by halting the process of iterations and thus, results in low computational complexity. Hence, by the addition of LSQR, our proposed algorithm also exhibits above mentioned advantages. Simulation results of our recommended hybrid method validate its significance over existing block and LSQR equalization techniques.