Research On Key Technologies Of 20Gbps Terahertz Communication Physical Layer

Terahertz band is a wireless band between visible light and microwave,which has potential applications in optics and communication.Its available bandwidth of tens of GHz provides a good condition for high-speed communication.With the increasing material and cultural needs of people,the transmission rate of wireless communication such as mobile Internet and Internet of things has put forward higher requirements.Terahertz communication has become a research hotspot in wireless communication industry.In this paper,a physical layer system of Zero-IF transceiver is designed.It mainly involves the following work:Firstly,several commonly used terahertz frequency conversion modulation schemes are discussed and compared.Among them,Zero-IF transceiver is adopted as the RF modulation scheme of this subject because of its smaller size and lower cost.Secondly,the application of synchronization technology and equalization technology in digital baseband signal processing is described.Aiming at the problem of IQ imbalance existing in Zero-IF transceiver system,the frequency domain adaptive equalizer with two groups of taps is used as IQ correction algorithm.Thirdly,it analyzes the application scenarios and requirements of 20Gbps terahertz communication link,designs the physical layer scheme of communication link,adopts OFDM waveform system and 16QAM symbol modulation mode.The time synchronization scheme and IQ correction scheme are mainly introduced,and the link performance is simulated in detail.Fourth,the physical layer of terahertz communication is implemented on FPGA chip.32 parallel resources are used to complete digital signal processing.Virtex Ultra Scale+series chips are equipped to meet the requirements of high throughput and chip resource consumption of physical layer.The implementation model of time synchronization and channel equalizer is given in detail.Fifthly,the link performance is tested in 220GHz band.the communication bandwidth is 5.2GHz,the data rate is 20.8Gbps,the EVM is-18d B and the BER is below10^-6at 15m communication distance.This paper designs and implements a terahertz communication physical layer for Zero-IF transceiver,which can meet the demand of 20Gbps.The work of this paper provides a verification system for terahertz wireless communication.After engineering implementation,the research results have theoretical and practical value.The experimental data provide support for terahertz communication.