Delay-aware resource allocation for 5G wireless networks with wireless power transfer

For 5G wireless networks, low latency and high energy efficiency are two of the most critical key performance indicators. In this work, we propose a framework to consider these requirements simultaneously by applying the notions of effective capacity, effective energy efficiency, and simultaneous wireless information and power transfer (SWIPT). At first, we define the effective capacity and the effective energy efficiency of SWIPT in multiuser orthogonal frequency division multiple access systems by considering two practical schemes of SWIPT: time switching (TS) and power splitting (PS). Afterwards, we formulate two resource allocation problems to maximize the effective capacity and effective energy efficiency, respectively, subject to three constraints: minimum harvested power, average sum transmit power, and delay quality of service. Numerical results illustrate that there is a fundamental tradeoff between harvested power and the performance in terms of effective capacity and effective energy efficiency. Moreover, the efficiency of PS scheme over TS greatly depends on the minimum required harvested power and the number of users.