Cooperative HARQ Assisted NOMA Scheme in Large-scale D2D Networks

This paper develops an interference aware design for cooperative hybrid automatic repeat request (HARQ) assisted non-orthogonal multiple access (NOMA) scheme for large-scale device-to-device (D2D) networks. Specifically, interference aware rate selection and power allocation are considered to maximize long term average throughput (LTAT) and area spectral efficiency (ASE). The design framework is based on stochastic geometry that jointly accounts for the spatial interference correlation at the NOMA receivers as well as the temporal interference correlation across HARQ transmissions. It is found that ignoring the effect of the aggregate interference, or overlooking the spatial and temporal correlation in interference, highly overestimates the NOMA performance and produces misleading design insights. An interference oblivious selection for the power and/or transmission rates leads to violating the network outage constraints. To this end, the results demonstrate the effectiveness of NOMA transmission and manifest the importance of the cooperative HARQ to combat the negative effect of the network aggregate interference. For instance, comparing to the non-cooperative HARQ assisted NOMA, the proposed scheme can yield an outage probability reduction by 32%. Furthermore, an interference aware optimal design that maximizes the LTAT given outage constraints leads to 47% throughput improvement over HARQ-assisted orthogonal multiple access (OMA) scheme. Index Terms Zheng Shi and Shaodan Ma are with the Department of Electrical and Computer Engineering, University of Macau, Macao (e-mails:[email protected], [email protected]). Hesham ElSawy and Mohamed-Slim Alouini are with the Computer, Electrical, and Mathematical Science and Engineering (CEMSE) Division, King Abdullah University of Science and Technology (KAUST) Thuwal, Makkah Province, Saudi Arabia (e-mail:[email protected], [email protected]). Guanghua Yang is with the Institute of Physical Internet, Jinan University (Zhuhai Campus), Zhuhai, China (email:[email protected]). July 14, 2017 DRAFT 2 Device-to-device communications, non-orthogonal multiple access, hybrid automatic repeat request, cooperative communications, stochastic geometry.