Research On Submillimeter Wave Multiplier

Terahertz technology has a high prospect of application and development in the fields of information science,space science,medicine science and material science.The terahertz band is the connecting band between radio wave and infrared,and its long wave segment in 100GHz-300GHz is of great value in radar communication,imaging,detection,counter-terrorism,biomedicine,food,environment detection,astronomical observation and so on.But since the THz wave generation and detection limits the realization of these applications,so the relevant research institutions have to solve this problem with a lot of researches.The terahertz solid sources based on semiconductor play a great role.The terahertz solid source has a compact structure,and it can work at room temperature with the feature of high reliability and low cost.And a key component of this kind of frequency source is the multiplier which is also an emphases in this thesis.However,the input power of the multiplier based on GaAs is limited so that the output power is limited.This thesis targets on the problem to carry out the following research.This topic studies two kinds of 110GHz tripler using GaN diode.Through reading a large number of papers from domestic to foreign field related to triplers,the principle of frequency doubling has studied deeply,and after the analysis of the overall circuit,finally choosing the parallel structure to design these triplers.In the process of researching,the three-dimensional electromagnetic model of the GaN planar Schottky diodes operated in the 110GHz band were analyzed and structured in detail using the software of HFSS which is designed for building 3D module structures.After studying the characteristic of GaN material and the advantage of GaN diode,the result of bearing voltage and power of GaN is much higher than GaAs can be concluded,which is suitable for the multiplier which requires high output power.The design of multiplier using GaN diode increases the experience of designing multiplier by GaN diode.The whole design includes the module of diode and the parts of passive structure,which will be simulated wholly in ADS.Then two triplers are completed after the physical assembly.For the first tripler,the experimental results show that when given the 200mW driven power,there is a maximum output power of 2.7mW at 108.6GHz,which gains the efficiency of 1.35%.When given the 400mW driven power,there is a maximum output power of 4.14mW at 109.8GHz,which gains the efficiency of 1.01%.For the second tripler;when given 200mW driven power,there is a maximum output power of 11.2mW at 114.3GHz,which gains the efficiency of 5.6%;when given the 300mW driven power,there is a maximum output power of 18.6mW at 114.3GHz,which gains the efficiency of 6.2%;when given the 400mW driven power,there is a maximum output power of 21mW at 114.3GHz,which gains the efficiency of 5.25%.Overall,the design using GaN planar Schottky diodes in this paper accumulates the experience of the application of GaN materials applied in the terahertz band to obtain high output power,which will be instructive in a certain sense.