Research On 220GHz Terahertz Broadband Receiving Front End

At present,the rapidly developed wireless communication technology leads to the increasingly scarce spectrum resources.It is necessary to turn our attention to the development of new bands to solve the problem.However,there are still a large number of spectrum resources that have not been fully exploited in terahertz band,making terahertz frequency suitable for future wireless communication as a new band.As the key technology of terahertz wireless communication,terahertz solid-state receiver plays an important role.In this paper,terahertz wireless communication system is studied,and a 220 GHz broadband terahertz receiving front-end is constructed by using the scheme of superheterodyne receiver.Firstly,after studying the principle of terahertz wireless communication system and analyzing the implementation method and difficulties of terahertz receiving front end,we propose a scheme of superheterodyne receiver.Secondly,the key devices of terahertz receiving front end are developed according to the proposed scheme,which includes mixer,local oscillator link,filter and IF signal processing module.The frequency conversion circuit of the system is elaborated in detail,including: introducing the basic frequency conversion principle of planar Schottky diode and modeling its simulation;developing and testing 220 GHz sub-harmonic mixer which shows that the frequency conversion loss of the mixer is less than 14 dB in the frequency band of 200-240 GHz when the local frequency is 110 GHz;designing the local oscillator link of mixer,which shows that the local oscillator link can output 110 GHz signal of 5.5 mW.Finally,the 220 GHz terahertz receiving front-end is constructed by using the key devices of the terahertz receiving front-end,and it can be used to transmit a 16 QAM modulated signal as a wireless communication system.Through the research of this paper,a terahertz wireless communication system is built,which verifies the feasibility of the practical application of terahertz wireless communication.