摘要：A frequency-multiplied source at the terahertz band using discrete planar Schottky diodes, which is a critical element in heterodyne instruments, has been studied by some domestic research institutions in recent years. Besides the design method, there are still many crucial problems that must be taken into consideration in the design. This article mainly discuss three aspects based on the measured data of a 225 GHz tripler that we designed. Firstly, the accuracy of the diode model concerns the reliability of the simulation results. According to the Spice parameters and the measured results, the physical size and the DC parameter of the Schottky diode can be corrected until there is a good consistency between the simulated and measured results. Secondly, the heat accumulation happens to the Schottky junction when the high input power is added. A steady-state thermal simulation is done and the results show that the hottest temperature is about 140℃ with 250 mW input power, which is safe to the diode. Lastly, some non-ideal factors are brought during the assembly process such as the uncertainty in the conductive adhesive shape and location deviation of the circuit. Furthermore, the effect on the performance of the frequency multiplier is calculated in this work.

摘要：为了实现对地球大气痕量气体探测的目的,提出了一种基于FPGA的太赫兹频谱仪数字单元设计方案,完成了系统的硬件和软件设计。该数字单元硬件部分由四路ADC完成2.4 GHz信号采样,一片FPGA芯片完成信号复用和FFT频谱运算,ADC选用ADC083000,FPGA芯片为Xilinx Virtex-5系列。由VHDL编程实现对系统各部分功能的控制。通过Chip Scope工具进行功能验证,该数字单元稳定可靠,可以运用于临边探测仪中。