Folded Waveguide Line Transmission Characteristics In The Thz Devices

Terahertz technology is a brand-new electromagnetic wave technology, also being a hot topic in recent years and valued as one of the ten science technologies influencing the future of the world. People used to know very few about terahertz wave limited by lacking effective way of transmitter and detection before 80's of 20th century. The rapid development of ultra-fast laser technology offers a stabile and reliable laser source for production of terahertz radiation pulses, which promotes the broad application of terahertz technology to fields in basic research, industry and military affairs.Scarcity of small, economical terahertz source which can offer continuous wave of high average power is the main limitation for a broad application of terahertz technology. The research of terahertz source has been addressed in many countries and gotten rapid and very important progress. But the research in our country is still at beginning. This thesis will introduce a new terahertz source which based on vacuum electronics, transmission characteristics of the high frequency system and the process of interaction between electron beam and the high frequency traveling-wave have been researched, which offers basic technology for further deep development of terahertz source technology basd on vacuum electronics in our country. The main research is as follows:Firstly, progress of terahertz technology research in our country is analyzed and summarized. A new terahertz source of folded waveguide traveling-wave-tube which based on vacuum electronics is introduced, which may answer the question for scarcity of small, economical terahertz source with continuous wave of high average power.Secondly, transmission characteristics of terahertz wave in the periodic slow wave circuit of folded waveguide traveling-wave-tube have been researched combined with development of micro-fabrication technology. Dispersion relation and interaction impedance of the slow wave circuit are deduced by the way of equivalent circuit, and results accounted by theory are close to those simulated by software. It is proved that this circuit has a good transmission characteristic with broad frequency range and low loss.