Side information embedding and detection scheme for selected mapping based single-carrier frequency-division multiple access systems

Selected mapping (SLM) works effectively in peak-to-average power ratio reduction for the single-carrier frequency-division multiple access (SC-FDMA) system. However, the need for side information (SI) transmission results in data rate loss and increase of the system complexity. To avoid explicit SI transmission for SLM-based SC-FDMA systems, an SI embedding and detection scheme is proposed by exploiting the block pilot symbols. Specifically, to enable SI embedding, the authors propose to represent the SI index for each data symbol in the subframe by a location set of some selected subcarriers in the block pilot symbol. For SI detection, an optimal pilot-aided maximum-likelihood SI detector is presented. As a low-complexity alternative, a suboptimal log-likelihood ratio SI detector is also proposed. In addition, the authors provide theoretical analysis of SI detection error rate and discuss the effect of the proposed scheme on channel estimation. Simulation results show that, in SLM-based SC-FDMA systems, the proposed scheme significantly outperforms existing methods in terms of both SI detection and bit error rate (BER) and achieves the same BER performance as its counterpart with perfect SI.