Dual-band Full Duplex RF Transceiver System

The limit of spectrum resources is a significant factor which influences the development of communication industry.How to improve the utilization of spectrum resources has been one of the most important issues in the field of communication research.In order to further improve the utilization of spectrum resources,the commercial communication system is divided into frequency division duplex(FDD)and time division duplex(TDD)and widely used in duplex technology at present.After FDD and TDD,Co-frequency Co-time Full Duplex(CCFD)has been proposed,which means receive and transmit signals at the same time slot in the same frequency band,the spectrum efficiency is doubled compared with the existing FDD and TDD.Therefore,the study of full duplex technology has important theoretical and practical value.The existing research results show that the research work of full duplex self-interference cancellation is mainly concentrated in a single frequency band,the study of dual-band full duplex self-interference cancellation will be a new direction.In this thesis,a new dual-band full duplex analog self-interference cancellation architecture is proposed,which initiatively achieve dual-band full duplex self-interference cancellation.The research of this paper contents on dual-band full duplex analog self-interference cancellation system,which mainly includes:(1)The basic concepts and research status of full duplex communication are introduced in detail.(2)A dual-band passive self-interference cancellation system accompanied with a dual-band circularly polarized antenna and a dual-band branch line coupler is designed.,which is based on the analysis of the existing full duplex passive self-interference cancellation system,and the system is simulated in ADS.(3)On the basis of analysis of the existing positive self-interference cancellation structure,this paper designs a multi-path full duplex positive self-interference cancellation system,and details the theory of this passive self-interference cancellation and chip selection,and the design of the key parameters of the system.(4)In the laboratory condition,the dual-band full duplex radio frequency transceiver system realized in this paper has been tested,and the test results meet the design requirements.