Design of SIMO SC-FDMA-DMWT Transceiver using Maximal-Ratio Combining in LoS Fading Channels

Abstract

In this paper single-input multiple-output (SIMO) transceivers employing single-carrier Frequency Division Multiple Access with Discrete MultiWavelet Transform (SC-FDMA-DMWT) for 3GPP Long Term Evolution (LTE) uplink channels are considered. While SC-FDMA-DMWT traditionally underperforms compared to Orthogonal Frequency Division Multiplexing (OFDM) in Rayleigh fading, line-of-sight (LoS) components significantly enhance its resilience to fading. This study evaluates Maximal-Ratio Combining (MRC) effectiveness for SC-FDMA-DMWT through systematic comparison with ZeroForcing (ZF) and Minimum Mean Square Error (MMSE) equalizers under varying LOS power levels and antenna correlations Monte Carlo simulations perform bit processing at the level of 2×10⁶ per configuration for SNR that ranges from –5 to 25dB using realistic LTE channel models in both Rician and Rayleigh fading cases. Performance measures are BER analysis and diversity gain calculation. Results demonstrate that MRC-based SC-FDMA-DMWT achieves an 8-9dB BER improvement at 10⁻⁴ compared to conventional OFDM in LoS-dominant channels. The Frequency correlation impact becomes negligible with MRC implementation, indicating optimal signal combining performance, translating to 75-85% transmit power reduction in Dual-antenna SIMO structures, while preserving the natural low PAPR characteristics of the SC-FDMA scheme. Centralized 12-subcarrier assignments perform 4-6 dB better than decentralized 48-subcarrier settings. These results confirm that SIMO SC-FDMA-DMWT with MRC is a promising candidate for next-generation LTE uplink systems, particularly in macro and small cell deployments under dominant LoS propagation conditions.