W波段测量辐射计接收机设计

【作者】 曾文辉；

【导师】 彭树生；

【作者基本信息】 南京理工大学 ， 信号与信息处理， 2008， 硕士

【摘要】 本文详细研究了W波段K因子型测量辐射计系统,设计了辐射计接收机的系统参数,实现了接收机的中频放大器组件和低频电路组件。在理论分析方面,讨论了适合应用背景的全功率辐射计和迪克辐射计及其两种变化形式,分析了它们的工作原理。针对它们的性能和在国内现有条件下的实现难度,比较了它们的优缺点,在此基础上确定了系统的实现方案。系统采用K因子型辐射计体制,考虑到国内设计和购买低噪声放大器(LNA)的难度,分别考虑了有、无W波段低噪声放大器LNA情况下的两种实现技术途径。文中详细分配了接收机各组件的参数指标,计算了各组件的主要性能参数。对整个设计系统进行了仿真,仿真结果与设计结果完全吻合。同时,由于系统采用超宽带中频接收方案,为分析各次谐波对系统的影响而对系统进行了谐波仿真,结果表明系统对谐波的抑制性能良好。在系统具体设计方面,讨论了毫米波多模喇叭天线的设计,给出了94.5GHz低副瓣多模喇叭天线的仿真结果。讨论了W波段低噪声放大器和混频组件等射频前端的设计。对中频放大组件进行了仿真和设计,仿真了中放组件中超宽带LC滤波器各元件值对系统各设计参数的影响;通过仿真实现了超宽带中频放大组件的优化设计,完成实物的调试,给出了实际调试结果。完成了平方律检波电路和低频电路组件的设计与调试。更多还原

【Abstract】 In this paper, a W-band K-factor radiometer system is studied for millimeter-wave radiation-measuring of subaerial object in detail, and the system parameter of the radiometer receiver is analyzed and designed, and its Intermediate Frequency Amplifier Module and low-frequency circuit assembly are realized.In theoretical analysis of the system, four types of a radiometer ,a total power radiometer, a Dicke radiometer and its two changing types, are discussed and their work principle are analyzed. Compared with their advantages and disadvantages in terms of their performance and implementing difficulty in the existing condition at home, this dissertation establishes the system scheme. Taked into account the difficulty in both the design and purchase of Low-noise Amplifier (LNA), a K-factor radiometer system is adopted with a LNA or without a LNA. In the paper, major parameters of all components of the receiver are assigned and computed in detail. After simulating the whole designing system, it’s found that results are consistent with the design value. At the same time, the harmonic performance is simulated to analyze its impacts on the Ultra-wideband IF Amplify Module, results show that the system has good harmonic suppression.In the system’s concrete design, a multi-mode horn antenna is used for the millimeter wave radiometer, whose side-lobe is under -35dB at 94.5 GHz for result of simulation with HFFS software. And a design of RF front-end, such as the W-band Low-noise Amplifier and mixer assembly, is discussed. Then this dissertation simulates and designs the IF Amplifier Module, and simulates effect of the Ultra-wideband LC Filter on the parameters of the IF Amplifier Module. Through simulation, the Ultra-wideband IF Amplifier Module is optimized and debugged. And the practical debugging results is shown well of the IF Amplifier Module. At last, the design and debug of the square-law detector and the low-frequency circuit assembly are achieved.更多还原