NOMA‐enabled D2D adaptive relaying and transmission in cellular networks

Abstract

With the aim of improving the spectrum efficiency, we propose a two-phase cellular non-orthogonal and device-to-device (D2D) non-orthogonal (CNDN) transmission scheme, wherein a base station (BS) can transmit data to a near-user and a far-user simultaneously assisted by two D2D users. Either the D2D transmitter or the D2D receiver can adaptively forward the BS data to the far-user according to their decoding statuses. When the D2D transmitter forwards the cellular data, it also transmits its own data to the D2D receiver simultaneously. The superposition coding technique is adopted for the non-orthogonal transmission and the opportunistic interference cancelation is performed for the data decoding. Taking into account the adaptive operations of cellular and D2D users, we analyze the throughput of both cellular and D2D systems. Extensive simulations show that the proposed CNDN scheme greatly outperforms the cellular orthogonal and D2D non-orthogonal (CODN) transmission scheme in terms of throughput. 1.Related worksDevice-to-device (D2D) communications enable adjacent devices to interchange data directly via bypassing the BS so as to reduce the cellular traffic load and provide more connection opportunities for more neighboring devices. 4 The short-distance D2D communications can lower down the transmit power and reduce the interference to other users. Furthermore, much higher spectrum efficiency (SE) can be achieved by avoiding the two-hop cellular transmission with the

Adaptive FRESH filter with vicarious reference for interference rejection: An application to signal detection in NOMA system

“…NOMA is getting to be an important empowering strategy for the future era of wireless networks where this multiuser transmission technique is based on superposition. 26 Power domain NOMA is a kind of NOMA schemes in which signals from different users and different power levels are superimposed at the transmitter and then transferred by using the same subcarriers. In this NOMA scheme, successive interference cancellation (SIC) is adopted by the receiver to detect the signals.…”

Joint bandwidth and power resource allocation technique in multi‐carrier non‐orthogonal multiple access‐based cognitive Internet of Things networks

“…However, non-orthogonal MA (NOMA) has been suggested as one of the most promising MA techniques for CR-based systems. 9,10 Unlike conventional OMA mechanisms, multiple NOMA-based users can be concurrently served over the same resource block using the power-domain multiplexing techniques. 11 This, in turn, adds an additional level of freedom, and thus, enables a larger number of users.…”

“…For example, CR with multiple antenna techniques, CR with traditional orthogonal MA (OMA) techniques. However, non‐orthogonal MA (NOMA) has been suggested as one of the most promising MA techniques for CR‐based systems 9,10 . Unlike conventional OMA mechanisms, multiple NOMA‐based users can be concurrently served over the same resource block using the power‐domain multiplexing techniques 11 .…”

“…Several previous studies looked into how to enhance system performance in hybrid OFDMA‐NOMA networks (eg, References 9, 10, 13, 14, and 24). In Reference 24, the sum‐rate maximization problem in a hybrid OFDMA‐NOMA system is studied while achieving a set of predefined design requirements.…”

“…The authors in Reference 19 proposed an energy efficiency (EE) maximization resource allocation mechanism for hybrid OFDMA‐NOMA systems. In Reference 9, the authors proposed a NOMA‐based device‐to‐device (D2D) transmission protocol with the objective of enhancing the overall spectrum efficiency. Their proposed protocol was shown to provide a significant throughput improvement over existing orthogonal cellular schemes.…”