On the application of SWIPT in NOMA networks

Abstract

Non-orthogonal multiple access (NOMA) is an effective solution to improve spectral efficiency and has recently received significant attention for its promising application in fifth generation (5G) networks. This chapter focuses on two communication concepts, NOMA and simultaneous wireless power transfer (SWIPT), which can be naturally linked together as a new spectrum and energy efficient wireless energy harvesting multiple access protocol. It uses the near NOMA users that are close to the source as relays to help the far NOMA users with weaker channel conditions. The chapter considers the application of SWIPT to NOMA, where SWIPT is performed at the near NOMA users. Three opportunistic user selection schemes are proposed based on the locations of users to perform NOMA as follows: random near user and random far user (RNRF) selection; nearest near user and nearest far user (NNNF) selection; and nearest near user and farthest far user (NNFF) selection.