Power Allocation Adaptation With Coherence Time for Nonorthogonal Multiple Access on Downlink Transmission

Nonorthogonal multiple access (NOMA) methods are expected to improve spectral efficiency or increase sum rate in a recent mobile communication network. The performance of the power-domain NOMA highly relies on the effectiveness of successive interference cancelation (SIC) and power allocation techniques. This paper proposes an adaptive power allocation method according to analytical coherence time of time-varying channels to improve the SIC effectiveness. Simulations show that the proposed technique can improve SIC, therefore reducing error probability without reduction of the sum rate.