【作者】 陈楠；

【导师】 高博；

【作者基本信息】 电子科技大学 ， 工程硕士（专业学位）， 2017， 硕士

【摘要】 混频器作为微波毫米波通信、雷达等系统的关键器件之一,其性能的好坏直接影响系统的性能指标。随着技术的不断发展,对混频器的特性参数要求也逐渐提高。因此,如何高速、精确的测量混频器的性能,已经成为了当前亟待解决的问题。混频器是一个三端口的非线性器件,传统的使用频谱仪或者功率计的方法只能测量混频器的变频损耗或者增益的幅度特性,而无法测量混频器的相频特性或者群时延。而随着通信、雷达等技术的发展,混频器的群时延成为一个关键的测量参数。本文介绍的基于矢量网络分析频偏功能对混频器进行测试的方法,不仅能够对混频器的变频损耗进行测量,还能够测量混频器的相频特性。混频器矢量校准算法是通过在校准期间使用校准标准件和一对校准混频器/滤波器组合来测量混频器的反射参数、变频损耗的幅度,相位和群时延等参数。主要分为三部分:第一部分是首先利用反射法获得校准混频器/滤波器组合的特性参数,并通过提取ADS仿真数据,利用MATLAB编程对校准混频器/滤波器组合的表征算法进行验证;第二部分是对混频器矢量校准算法进行理论推导,然后对已知参数的被测混频器进行仿真,利用MATLAB编程对混频器矢量校准算法进行验证。最后,通过矢量网络分析仪测量被测混频器的参数,通过误差修正算法得到准确的被测混频器的参数,并利用ADS仿真,分析了校准混频器不满足互易性要求或矢量网络分析仪端口匹配不好时,对测量精度的影响。本文在传统的双端口校准算法的基础上,研究并验证了混频器矢量校准算法,实现了混频器的变频损耗、相位及群时延的准确测量。对于微波电路和航空领域有着重要的意义。更多还原

【Abstract】 Mixer is one of the key devices in microwave and millimeter wave communication,radar and other systems.The performance of the mixer directly affects the performance index of the system.With the development of technology,the characteristic parameters of mixer are also gradually improved.So,how to measure the mixer’s performance characteristics in high precision simply and conveniently has been an urgent problem.The mixer is a nonlinear device with three ports.The traditional amplitude measurement method by spectrum analyzer and dynamometer can only determine its amplitude characteristic,and can do nothing in phase frequency characteristics and group delay measurement.With the development of communication and radar technology,the group delay has become a key parameter.In this paper,the method of mixer measurement by Vector Network Analyzer(VNA)based on frequency offset is introduced,which can not only measure the frequency conversion loss of mixer,but also can measure the phase frequency characteristics of mixer.Vector Mixer Calibration algorithm(VMC)is adopted in the calibration period using calibration standards and a calibration of mixer/filter combinations to measure reflectance parameters,mixer conversion amplitude characteristic,phase and group delay.The process can mainly divide into three parts: the first part is to obtain characteristic parameters of calibration mixer/filter combinations using reflection method,and by extracting the ADS simulation data,the calibration of mixer/filter combination characterization algorithm are verified by MATLAB programming;the second part is the theoretical derivation of VMC,then simulate the test mixer,which parameters are known,to verify the calibration algorithm by MATLAB program calculation;the last part is to measured and obtained the parameters of the mixer by a VNA,then calculate the true parameter through error correction algorithm,and analyzes the influence on the measurement accuracy of the mixer under the condition that the calibration mixer does not meet the requirement of reciprocity,based on ADS simulation.In this paper,we researched and verified the VMC,based on Two-port Calibration algorithm,realized accurate measurement for conversion loss,phase and group delay characteristics of mixer.This work has important significance for microwave circuit and aviation field.更多还原