Joint User-Channel Assignment and Power Allocation for Non-Orthogonal Multiple Access Relaying Networks

Abstract

Non-orthogonal multiple access (NOMA) technique, which is known to raise the performance of frequency spectrum constrained wireless communication networks, has obtained wide attention. In this paper, a NOMA-based resource allocation problem in the decode-and-forward relaying downlink network is considered. We aim to maximize the average user transmission rate, subject to the total system power constraint and users' quality of service requirement. A joint user-channel assignment and power allocation problem is formulated, which leads to an NP-hard problem requiring an exhaustive search. To tackle this problem, we adopt a decouple optimization method to separate the joint resource problem into two subproblems, a user-channel assignment problem, and a power allocation problem. After solving the two subproblems, a joint alternating optimization algorithm is proposed with low complexity. The simulation results show that the proposed joint optimal scheme can efficiently improve system performance in the limited channels of multiple users relaying networks. INDEX TERMS NOMA, user-channel assignment, power allocation, relay.

A Survey of Rate-Optimal Power Domain NOMA With Enabling Technologies of Future Wireless Networks

“…The proposed V2X-NOMA system with greedy/iterative 3-dimensional matching allocation algorithms achieve higher sum-rate performance with low/an acceptable increase in the computational complexity than that of V2X-NOMA/OMA system with random allocation algorithms (MRC). Recently, the adoption of the cooperative communication systems in conjunction with NOMA has received a lot of interest [163]- [165], [167], [168], [170]- [172], [174]- [176], [178]- [182], [184]- [188], [190]- [192], [197]- [199]. This is due to the advantage of the spatial diversity gain in improving the users' rate while enhancing the spectral efficiency of the network [179].…”

“…Subsequently, the users perform SIC procedures to decode the signal sent from the relay as described in Section II-A. This system model is adopted by several researchers [163]- [165], [167], [168], [170], [171]. 2) In this case the system model is similar to the previous one, but there exists an additional communication link between the BS and the strong user.…”

Joint Spectral and Energy Efficiency Optimization for Downlink NOMA Networks

“…The joint solution was obtained through a matching game and interior point methods. Similarly, Liang et al considered a resource allocation problem to enhance the user average data rate in cooperative NOMA network [26]. To tackle the NP-hard problem, they first decoupled the joint resource allocation problem into two separate sub-problems and then adopted two sub-optimal schemes based on matching game approach for the user sub-channel association and dual method for efficient power allocation.…”

Fairness‐aware power allocation in downlink MIMO‐NOMA systems

“…In addition, the heterogeneous network based on NOMA is presented in [24], where the authors investigate the trade‐off between the data rate and the energy consumption, and it shows that the proper power allocation can increase energy efficiency. In [25] the average rate maximized problem in decode‐and‐forward relaying downlink network is investigated where a joint user‐channel assignment and power allocation algorithm is proposed. In [26] and [27] the combination of millimetre and NOMA is introduced, in which optimal power allocation schemes for ideal beamforming are developed.…”