【作者】 潘博文；

【导师】 马洪；

【作者基本信息】 华中科技大学 ， 电磁场与微波技术， 2008， 硕士

【摘要】 用国内外现有的高速高精度数模转换器芯片或射频信号发生器产生的模拟信号的动态范围往往不能满足特殊应用系统的要求。为了提高输出模拟信号的动态范围和信噪比,可以利用滤波器对其杂谐波进行抑制。本文首先总结了设计集总参数LC滤波器的不同方法,并按照这些方法,利用ADS软件进行仿真和优化,在短波射频频段设计和制作了多路带通滤波器,以抑制信号源输出信号的带外杂谐波。本文同时设计了多路低通滤波器和带通滤波器的级联电路,以进一步提高带通滤波器的阻带抑制性能。基于LC带通滤波器的频域特性来进行滤波器调试是一件非常复杂繁琐的工作。本文研究了利用滤波器的时域反射特性、在网络分析仪中调试耦合谐振式带通滤波器的方法,并通过Matlab仿真和网络分析仪的实测结果,验证了这种时域调试方法的正确性。这种调试技术可望大大提高带通滤波器的调试效率。论文最后介绍了集总参数LC滤波器在高性能数据采集存储系统中的应用问题,特别是通过ADS的谐波平衡仿真技术分析和验证了LC滤波器在实际信号激励下出现的非线性失真现象,以及由此而引起的LC滤波器带外抑制性能的降低问题。这部分工作是迄今为止很少见诸公开报道的,其研究结论有助于选取合适的磁性材料以便设计大动态的线绕电感器。更多还原

【Abstract】 The SFDR of analog signal which is directly produced by the high-speed and high-accuracy analog-digital converter or the radiofrequency signal generator is always far from what is required for some special applications. To increase the SFDR and the SNR of the output signal, we could use the filters to suppress the spurious spectrum.Firstly, the thesis summarizes the different methods of designing the lumped parameter LC filter, and uses the software of ADS to simulate and optimize it. The thesis designs several band-pass filters to suppress the harmonics out of the pass band and spurs of the signal generator, and also designs several low-pass filters to connect the band-pass filters to increase the filters’ suppressing performance.It is a complicated work to tune LC band-pass filter in the frequency domain. However, the thesis makes a research about how to use the time domain waveform of the filter’s reflection to tune the coupled resonator band pass filter in the S-parameter network analyzer. The method of tuning the filter in the time domain proves to be reliable and is supported by the Matlab simulation and the analysis of the test results. Therefore, it is possible to improve the efficiency of tuning the band-pass filters greatly.Finally, the thesis introduces the application of the lumped parameter LC filters in the high performance data acquisition and storage system. The thesis also analyzes and validates the nonlinear of the LC filter which is encouraged by actual signal with the technology of the harmonic balance simulation of the ADS software. The nonlinear of the filter can give rise to the deterioration of the suppressing performance of the filter, and the conclusion of this research is helpful to choose the appropriate ferrite cores to design large dynamic inductors.更多还原