DeepAI AI Chat
Log In Sign Up

QoS-aware User Grouping Strategy for Downlink Multi-Cell NOMA Systems

by   Fengqian Guo, et al.

In multi-cell non-orthogonal multiple access (NOMA) systems, designing an appropriate user grouping strategy is an open problem due to diverse quality of service (QoS) requirements and inter-cell interference. In this paper, we exploit both game theory and graph theory to study QoS-aware user grouping strategies, aiming at minimizing power consumption in downlink multi-cell NOMA systems. Under different QoS requirements, we derive the optimal successive interference cancellation (SIC) decoding order with inter-cell interference, which is different from existing SIC decoding order of increasing channel gains, and obtain the corresponding power allocation strategy. Based on this, the exact potential game model of the user grouping strategies adopted by multiple cells is formulated. We prove that, in this game, the problem for each player to find a grouping strategy can be converted into the problem of searching for specific negative loops in the graph composed of users. Bellman-Ford algorithm is expanded to find these negative loops. Furthermore, we design a greedy based suboptimal strategy to approach the optimal solution with polynomial time. Extensive simulations confirm the effectiveness of grouping users with consideration of QoS and inter-cell interference, and show that the proposed strategies can considerably reduce total power consumption comparing with reference strategies.


Interference-aware User Grouping Strategy in NOMA Systems with QoS Constraints

To meet the performance and complexity requirements from practical deplo...

Joint Power and User Grouping Optimization in Cell-Free Massive MIMO Systems

To relieve the stress on channel estimation and decoding complexity in c...

Speed Based Optimal Power Control in Small Cell Networks

Small cell networks promise good quality of service (QoS) even for cell ...

On the Power Allocation Limits for Downlink Multi-user NOMA with QoS

The fundamental power allocation requirements for NOMA systems with mini...

Rate-Splitting Multiple Access for Cooperative Multi-Cell Networks

As a promising downlink multiple access scheme, Rate-Splitting Multiple ...

Optimal SIC Ordering and Power Allocation in Downlink Multi-Cell NOMA Systems

In this work, we consider the problem of finding globally optimal joint ...

A Note on Decoding Order in Optimizing Multi-Cell NOMA

In this technical note, we present a new theoretical result for resource...