Research On Multi-antenna Two-way Relay Cooperative Communication Technology In High-speed Railway

There are more complicated requirements for wireless communication technology in high-speed railway communication when comparing with traditional cellular wireless communication,due to the high mobility,complexity of environment and terrain,service integration,special requirements for train control and information transmission,etc.At the same time,with the advent of the 5G era,with higher rate requirements and lower latency requirements,the construction and evolution of high-speed rail communication networks are facing new challenges.This paper firstly studies the characteristics and shortcomings of the existing railway communication network GSM-R at the background of high-speed rail communication,and demonstrates its evolution in the 5G era.Secondly,based on the research direction of this paper,the development history of relay technology is briefly introduced.The importance of moving relay technology research in high mobility scenario is demonstrated.Then the development trend and current situation of the relay technology are expounded.Finally,after analyzing the core characteristics and advantages of multi-antenna two-way relay cooperative communication technology in high-speed railway,this paper proposes several improved optimization schemes.1)Based on the core technology of multi-antenna moving relay,this paper proposes a variable-density antenna arrangement for moving relay system which is suitable for high-speed rail communication.After derivation and simulation analysis,it is showed that the optimized antenna arrangement proposed in this paper not only improves the capacity of high-speed rail multi-antenna relay communication,but also smoothes the drastic changes of real-time communication capacity caused by the change of train and base station position.Futhermore,this paper proposes an antenna selection scheme,which can convert the performance improvement brought by optimizing the antenna arrangement into energy efficiency improvement or system connection stability.The simulation results also prove the effectiveness of this scheme.(Chapter Three)2)Based on the millimeter-wave beamforming technology,an optimized beamwidth generation scheme suitable for high-speed rail communication environment is proposed in this paper,to meet the high-speed rail communication needs in the 5G era.The design of multi-antenna moving relay is a continuation in this whole chapter.The scheme aims to apply the large-capacity feature of millimeter-wave communication to high-speed rail,meanwhile,avoiding the large attenuation characteristics of millimeter-wave communication.As using 5G high-low frequency C/U separation heterogeneous network,this paper designed a relay communication architecture with high communication speed and excellent energy efficiency.Through computational derivation and simulation analysis,the core features of the scheme are demonstrated.This scheme can adaptively adjust with the high speed/acceleration of the high-speed rail,thus providing higher communication speed and more stable communication quality.(Chapter Four)...