Abstract
Summary
This paper addresses the important and challenging issue of joint equalization of carrier frequency offsets (CFOs), timing offsets, and doubly selective channels (DSCs) of multiple users in a SC‐FDMA uplink. Low complexity, iterative equalizer solutions are proposed, which give impressive performance under rapidly varying channel conditions. We propose three different equalization schemes that make use of iterative interference cancellation technique named as iterative equalizer with interference cancellation (IEIC), iterative equalizer with interference cancellation and decoding (IEICD), and simplified iterative equalizer with interference cancellation and decoding (SIEICD). The SIEICD method proposed is a simplified version of the IEICD, and it makes use of the only significant elements in the receive signal model in the matrix form. The superior performance of the methods in high mobility conditions with several users is amply demonstrated through extensive simulation studies.
This work proposes novel low complexity iterative equalization techniques for SC‐FDMA uplink systems under doubly selective channels (DSC). The proposed techniques address the issue of equalizing the adverse effects caused by carrier frequency offsets (CFOs), integer timing offsets (ITOs), and DSC in SC‐FDMA uplink system in a high mobility communication environment. The work also proposes a simplified received signal formulation that can incorporate all impairments, such as CFOs, ITOs, and DSCs, and considerably reduces the complexity of the equalization task.