Phase Rotation Study And Reference Signal Design In 5G System

The 21st century is the era of information.As the primary means of information transmission,the communication technology is rapidly developing.Wireless communication systems are evolving all the time to meet the growing business needs of people.At present,the standardization of 5G is being carried out in order to achieve more comprehensive,faster and more efficient communication effect than the current 4G-LTE system.Compared to the previous communication system,5G applies many new technologies such as millimeter-wave,large-scale antenna,full-duplex technology.Meanwhile,5G adopts a new system architecture and working model.New technologies have also brought new problems,one of which is due to the higher frequencies,the phase noise and carrier frequency offset level,caused by the signal at the ends of the transceiver system hardware circuit oscillation become significantly higher than that of traditional wireless system,making the phase shift between symbols unable to ignore on the new system.So in order to eliminate the frequency offset caused by the increased bandwidth of the system,more reasonable reference signal design needs to be done.In addition,for 5G system,the design of the reference signal is also an important aspect of the standardized work.Scientific and reasonable design of reference signal is essential for the effective detection of wireless channel,the efficient transmission of signals as well as the reasonable scheduling planning.Aiming at the 5G system proposed by 3 GPP,based on the OFDM waveform of NR(New radio)interface,referring the existing research results and the physical layer standardized proposal,this paper do the analysis of the above two problems,attempting from the perspective of reference signal design to do the compensation for the phase shift of the new communication system for different scenarios,different schemes of phase shift,analyses and comparisons the reference signal design are discussed.The main contributions of this thesis include:1.According to the 3 GPP standardization proposal and the Chairman’s Notes,the 5G link level simulation platform is developed,by using the new channel model,frame structure and channel estimation algorithm,etc.,making the study more close to 5G real evolution scenarios.2.Comparing the fixed carrier frequency offset and phase noise scenarios,different reference signal design pattern,different densities of the TRS to the compensation effect of phase rotation.3.Based on OFDM waveform,a comprehensive design is presented which has taken into consideration the sequence generation of the reference signal,the patterns,control signal,and etc.4.For SC-FDMA waveform,a novel design about reference signal is proposed to reduce PAPR.