A Joint Multi-Service Transmission Scheme For Cell-Free MMIMO System

In today’s mobile communication environment,service types are becoming more and more diversified,and providing users with multiple services at high rates and high quality has become the main goal of nextgeneration wireless communication systems.In the study of joint multiservice transmission under cellular networks,Rate-Splitting(RS)technology can realize joint transmission of broadcast,multicast,and unicast with effective spectrum efficiency,but based on its underlying architecture of cellular networks,edge effects and cell interference have a negative impact on system performance.Cell-Free(CF)networks are considered as one of the key promising technologies in the 6th Generation Mobile Communication(6G)era,as a distributed technology with stronger resistance to shadow fading and reduced cell edge effects.This article focuses on the multi-service transmission scheme in cellfree network architecture,and mainly studies the following:Firstly,we propose a multi-service transmission scheme based on cellfree network to address the problem of large inter-cell interference in the existing scheme under the cellular network,and derived the transceiver model of the scheme in detail.Finally,the simulation results show that the proposed scheme can effectively improve the sum rate and performance of the system.Secondly,for the proposed joint multi-service transmission scheme,a stepwise algorithm with lower complexity is proposed to solve the resource allocation problem with the objective of maximizing the system sum rate,the original optimization problem is reduced in dimensionality and solved separately.Simulation results demonstrate that the algorithm is able to provide higher system and rate performance.Thirdly,the stepwise algorithm is further optimized and a joint resource allocation scheme is proposed.The two sub-problems of AP and user matching and power allocation are solved jointly by iterative optimization to obtain higher system performance gain by joint iterative processing.Simulations prove that this scheme has higher performance gain than the traditional resource allocation scheme and the above proposed stepwise scheme,but has the problem of higher complexity,which requires a trade-off between performance and complexity.