Performance analysis of multiuser detection and decoding for subcarrier hopping multiple access

Real-time wireless communications such as motion controls of vehicles and machines have been attractive in recent years, in which latency and reliability are of significant importance. A new orthogonal frequency-division multiplexing (OFDM)-based uplink multiple access system called subcarrier hopping multiple access (SHMA) can achieve high reliability due to both coding gain and frequency diversity gain without increasing decoding delay by combining super-orthogonal convolutional codes (SOCC) with subcarrier hopping. In order to improve the spectral efficiency, multiple users should share the same set of subcarriers together with multiuser detection and decoding (MUD) at the receiver to mitigate multiple access interference. In this work, we focus on two representative MUD schemes, i.e., super-trellis decoding (STD) and successive interference cancellation (SIC), and develop approximate bit error rate expressions when each MUD scheme is employed. Through the comparison with simulation results, we demonstrate that our analysis is useful for predicting the behavior of MUD. Also shown is the effectiveness of our proposed hopping design in fully achieving frequency diversity gain over static fading channels.