Non-Orthogonal Multiple Access for 5G and Beyond

Abstract

Driven by the rapid escalation of the wireless capacity requirements imposed by advanced multimedia applications (e.g., ultra-high-definition video, virtual reality etc.), as well as the dramatically increasing demand for user access required for the Internet of Things (IoT), the fifth generation (5G) networks face challenges in terms of supporting large-scale heterogeneous data traffic. Non-orthogonal multiple access (NOMA), which has been recently proposed for the 3rd generation partnership projects long-term evolution advanced (3GPP-LTE-A), constitutes a promising technology of addressing the above-mentioned challenges in 5G networks by accommodating several users within the same orthogonal resource block.By doing so, significant bandwidth efficiency enhancement can be attained over conventional orthogonal multiple access (OMA) techniques. This motivated numerous researchers to dedicate substantial research contributions to this field. In this context, we provide a comprehensive overview of the state-of-the-art in power-domain multiplexing aided NOMA, with a focus on the theoretical NOMA principles, multiple antenna aided NOMA design, on the interplay between NOMA and cooperative transmission, on the resource control of NOMA, on the co-existence of NOMA with other emerging potential 5G techniques and on the comparison with other NOMA variants. We highlight the main advantages of power-domain multiplexing NOMA compared to other existing NOMA techniques. We summarize the challenges of existing research contributions of NOMA and provide potential solutions. Finally, we offer some design guidelines for NOMA systems and identify promising research opportunities for the future.

Performance Evaluation of Successive Interference Cancellation on Gain Ratio Power Allocation using Underwater Visible Light Communication Channel

“…However, it is rare to find a propagation channel like this at the implementation stage in the real world. The formula for calculating channel gain in this LOS propagation channel model can generally be seen in the following formula [16]:…”

Spectral-Energy Efficiency Trade-off-based Beamforming Design for MISO Non-Orthogonal Multiple Access Systems

“…Note that the constraint in ( 24) is always held true for any set of channel coefficients and beamforming vectors, and thus, is not required to be included in the optimization problem. Now, we take the square-root of both sides in (23a) after incorporating the new approximation in (24). Next, the righthand side of this inequality can now be approximated with linear function using the first-order Taylor series approximation.…”

“…For instance, incorporating NOMA with the multiple-antenna techniques was considered in [20]. Another example is multiple-input single-output (MISO)-NOMA [21] [22] [23], which can be classified into two main categories: beamformer-based and cluster-based MISO-NOMA schemes [24] [25]. In this paper, we focus on the beamformer-based MISO-NOMA scheme, where each user is served by a single beamforming vector.…”

Efficient resource allocation for hybrid nonorthogonal multiple access based heterogeneous networks beyond fifth‐generation

“…1 The researchers are continuously working to accommodate the future projected traffic by exploring extreme densification and suitable multiple access (MA) techniques. 2,3 The extreme densification or heterogeneous network (HetNet) includes a family of small base stations (SBSs) in addition to the existing macro base station-only (MBS-only) network to move users closer to wireless access point. 4 SBSs are small-sized, low-cost, minimum power consumption base stations (BSs) that include microcell, picocell, and femtocell.…”