BER Analysis for two-hop Co-operative Non-orthogonal multiple access (CNOMA) relaying scheme
Non-orthogonal multiple access (NOMA) is the remarkable multiple access technique to achieve the desirable system capacity. In order to upgrade the spectral efficiency of cell-edge users, cooperative non-orthogonal multiple access (CNOMA) is engaged in a system, where downlink signal is transmitted after performing superposition coding (SC). In order to see the BER performance, we derive the expressions for error probability. The proposed scheme can provide a reasonable increase in transmission rate of a cell-edge user without degrading the rates of near users. A sumptuous deal with recent attention has been devoted to analyze the CNOMA system. Until now, the exact bit error rate (BER) expressions for proposed downlink CNOMA relaying systems have not been reported yet. In this article, we provide the exact closed-form BER expressions for binary signaling schemes for downlink CNOMA system over additive white Gaussian noise (AWGN) channel. Finally, the derived BER expressions are verified through Monte Carlo simulations. The proposed scenario increases the BER, however it accommodates multiple users on a single carrier.
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