BER Performance of Multicast SCMA Systems

Sparse code multiple access (SCMA) and wireless multicast are viewed as two effective techniques to improve spectral efficiency. Due to the diversity of channel gains for different receivers in the multicast group, the bit error rate (BER) analysis of the unicast SCMA is not suitable for the multicast SCMA systems. Motivated by this, in this letter, the BER performance of multicast SCMA system with randomly deployed receivers is investigated. More specifically, we derive a tight upper bound expression for the BER of the system. To gain more insights of the expression, asymptotic analysis is conducted. Both theoretical and simulation results show that the BER increases as the number of receivers increases in the multicast group.