| In the 5th Generation Mobile Networks(5G),video surveillance,machine cooperation and other large uplink services and low latency requirements have emerged.In order to further explore the spectrum potential,relieve the pressure of insufficient spectrum resources,and improve the uplink throughput of the system,it is necessary to introduce the sub-band full duplex mode on the Time Division Duplex(TDD)spectrum.However,the application of the sub-band full duplex technology will bring stronger interference to the system.In order to study the performance of 5G New Radio(NR)system in the sub-band full duplex mode,it is necessary to consider the coexistence of system interference under the sub-band full duplex mode.We focus on the interference coexistence of NR systems in the sub-band full duplex mode.The research contents of this thesis include interference coexistence in the macro-cell system and interference coexistence between the macro-cell and indoor hotspot systems under the sub-band full duplex mode.The system models and interference scenes of macro-cell and indoor hotspot are analyzed in detail,and the interference evaluation criteria and simulation methods of sub-band full-duplex scenes are studied.The simulation platform of full-duplex system was built based on Monte Carlo simulation method,and the system-level simulation method different from the half-duplex scene was proposed.Through the simulation analysis combined with the interference coexistence evaluation criteria,the isolation degree required by the system was proposed.The thesis mainly includes the following two parts.The first part is the study of interference coexistence in the macro-cell system in the sub-band full duplex mode.Firstly,the interference of the macro-cell system in the sub-band full duplex mode is analyzed,and then the propagation model,antenna model,uplink power control model,link level-to-system level mapping model,self-interference elimination model,adjacent channel interference ratio model suitable for the macro-cell system are introduced.In addition,the evaluation criterion and simulation method of interference coexistence are proposed.Finally,Monte Carlo simulation method was used to model the system.According to the simulation method of the full duplex system,the interference coexistence simulation analysis of the city macro cell system in the sub-band full duplex scene was carried out and the simulation results of the user side and the base station side are respectively given.According to the simulation results and evaluation criteria of sub-band full duplex scenarios,the system isolation and uplink capacity gain under different sub-band configurations are proposed.The second part is the study of interference coexistence between macro-cell system and indoor hotspot system in sub-band full duplex scenario.This thesis introduces the indoor hotspot system model which is different from macro cell,and gives the calculation method of interference between indoor hotspot system and macro-cell system.Based on the overlapping coverage range between the two systems,the coverage scenarios of macro cell and indoor hot spot are defined,and the simulation method between the two systems in the full-duplex scenario is proposed.Firstly,the interference coexistence simulation between the two systems was carried out in the TDD scenario,and the isolation index was obtained in the TDD scenario.Then,the interference coexistence simulation between the two systems was carried out in the sub-band full duplex scenario of the macro-cell.By analyzing the corresponding simulation results,the isolation degree required by the interference coexistence of the two systems in the full-duplex scenario and the half-duplex scenario is obtained,and the isolation degree between the two systems is proposed. |
