Throughput Enhancement on the Downlink of 4G and 5G Systems: NOMA, BOMA and IBOMA

Background & Objective: Non-orthogonal multiple access (NOMA) is compared with building block sparse constellation based orthogonal multiple access (BOMA) on the downlink of the long term evolution (LTE) system. Both NOMA and BOMA can enhance the overall throughput by additionally transmitting bits of a strong user when transmitting bits of a weaker user. It is shown that both NOMA and BOMA have the same transmitted signal format that emerge from the building block approach for designing multilevel codes (BB-MLCs). However, BOMA decoding is simpler than NOMA decoding. Result: Numerical results demonstrate that both NOMA and BOMA perform almost the same way and they both introduce a significant performance loss for the weaker user. Conclusion: A novel improved BOMA (IBOMA) technique is proposed to significantly lower that performance loss for the weaker user.