Admission Control and Power Allocation for NOMA-Based Satellite Multi-Beam Network

Ruisong Wang,Gongliang Liu,Wenjing Kang,Bo Li,Ruofei Ma

doi:10.1109/access.2020.2973395

Abstract

This paper investigates the admission control problem on the satellite multi-beam networks with non-orthogonal multiple access (NOMA). The goal is to maximize the number of supported users on the premise of ensuring the quality of service (QoS) by optimizing the subchannel and power allocation. We provide the system model and then formulate the admission control problem as a mixed integer non-convex optimization problem. The non-convexity and existence of integer variable make the optimal solution difficult to get. Therefore, we propose a joint subchannel matching and power allocation algorithm to obtain the suboptimal solution so as to reduce the computation complexity. The proposed algorithm can be used for both NOMA and orthogonal frequency division multiplexing access (OFDMA). Specifically, the subchannel matching problem is solved by a two-stage matching process where users are accessed to subchannel dynamically. The power allocation problem is modeled as a super-modular game where the existence and uniqueness of Nash equilibrium (NE) are analyzed. Moreover, an iterative power allocation algorithm is proposed based on the NE searching method. Finally, simulation results are provided for demonstrating the effectiveness and feasibility of the proposed algorithm.

Highlights

With the increasing of new services and the shortage of spectrum resource in the future satellite communication systems, multi-beam satellite system has been paid more attention due to its advantages of increasing the capacity and allowing frequency reuse
Motivated by the analysis above, we investigate the application of non-orthogonal multiple access (NOMA) in multi-beam satellite system and consider the admission control problem
Compared with some existing works that set up the utility function as the channel gain value, we provide a dynamic update strategy for the utility function of users according to the current subchannel matching state

Summary

Introduction

With the increasing of new services and the shortage of spectrum resource in the future satellite communication systems, multi-beam satellite system has been paid more attention due to its advantages of increasing the capacity and allowing frequency reuse. To ensure the performance requirement, how to efficiently allocate the limited resources to manage the interference among beams is a hot topic now. In [1], the authors proposed a robust on-board beamforming scheme by considering the effect of both forward and return link. Due to reusing the same frequency band among different beams, co-channel interference from multiple beams always exists. Some works focus on resource allocation and interference management to improve the performance of the system. In [4], the authors proposed a power allocation scheme by using a Stackelberg game model and analyzed the effect of price on the performance. In [5], a two-stage approach aiming at optimizing multiple objects was studied to designing the power allocation algorithm

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Results

Conclusion