Yinghua Zhang1,2, Yanfang Dong2, Lei Wang1, Jian Liu1,*, Yunfeng Peng1, Jim Feng3
CMC-Computers, Materials & Continua, Vol.60, No.1, pp. 379-393, 2019, DOI:10.32604/cmc.2019.05790
Abstract In this paper, we propose a downlink cognitive non-orthogonal multiple access (NOMA) network, where the secondary users (SUs) operate in underlay mode. In the network, secondary transmitter employs NOMA signaling for downlink transmission, and the primary user (PU) is interfered by the transmission from SU. The expressions for the outage probabilities are derived in closed-form for both primary and secondary users in the presence of channel estimation error. Numerical simulation results show that the channel estimation error and the inter-network interference cause degradation of the downlink outage performance. Also the power allocation and the location More >