Multi-user Transmission Strategy And Performance Evaluation For Dual-hop PLC/RF Communication Systems

Compared with the single Power Line Communication(PLC)and Radio-Frequency(RF)wireless communication technology,PLC/RF hybrid communication system can integrate the advantages of both,and show a broad application prospect in smart grid and home Internet of things and other fields.This paper mainly aims at several typical scenarios in the hybrid double-hop PLC/RF system,proposes the corresponding transmission strategy,and further analyzes the system performance,which provides technical support for the actual system design.The main work of this paper is as follows:1.For multi-user PLC/RF communication system,an opportunistic scheduling scheme based on threshold judgment is proposed,which can reduce the feedback load and obtain good performance.Secondly,under the circumstance that the PLC link is affected by background noise and pulse noise,and its channel fading is modeled as log-normal(LN)distribution,while the RF link follows the correlated Rice distribution,the closed expressions of the outage probability and the normalized average feedback load of the system are derived.Furthermore,the diversity and array gain are obtained by deducing the approximate expression of system outage probability under high signal-to-noise ratio.Finally,the computer simulation verifies the correctness of the theoretical derivation and the superiority of the proposed scheme.2.For PLC/RF communication system using Non-Orthogonal Multiple Access(NOMA)in multiservice coexistence,a power distribution scheme was proposed.It can improve the outage performance of data user while ensuring the Quality of Service(Qo S)of control user.Secondly,under the circumstance that the PLC link is affected by background noise and pulse noise,and its channel fading is modeled as LN distribution,while the RF link is subject to the correlated Rice distribution,the closed expressions of the outage probability of the data user and the average block error rate of the control user are derived.Finally,the computer simulation verifies the correctness of the theoretical derivation and the superiority of the proposed scheme.3.For multi-user PLC/RF communication system which adopts massive Multiple Input Multiple Output(MIMO),firstly,a semi-grant-free random access scheme is proposed,which can avoid the interference to other users caused by preambles collision.Secondly,under the circumstance that PLC link is affected by background noise and pulse noise,and its channel fading is modeled as LN distribution,while RF link is modeled as Rayleigh fading channel,the probability of connection success under grant-free random access and semi-grant-free random access schemes is derived.Finally,the computer simulation verifies the correctness of the theoretical derivation and the difference of the performance of different schemes.