Theoretical And Experimental Research Of Frequency Converter And Chain Vector Calibration Algorithm

Frequency-converter device is one of the basic components in RF or microwave transceiver system.It is used to describe the chain made up of mixer,filter,amplifier,etc..The performance of its parameters will directly affect the performance of the system.Controling its performance will ensure the accuracy of system.The mixer is the most important frequency converter device.If the accurate measurement of mixer can be finished,it also has reference significance for the measurement of frequency-converter device.In some traditional methods,the mixers are measured by spectrometers or power meters.However,these traditional methods only measure amplitude response.And serious phase distortion would cause FM signal distortion or aggravate intersymbol interference.The vector mixer calibration algorithm studied in this paper can achieve accurate measurement of amplitude and phase.The vector mixer calibration algorithm measures and corrects the conversion loss and group delay parameters of the DUT through a reference mixer and a set of calibration mixer/filter.Another vector mixer calibration algorithm based on unknown through also use same devices,but the latter use different error model than the former to complete the correction of eace parameters.After the theoretical derivation,these vector mixer calibration algorithms are simulated by the ADS simulation software and the actual test,and the results are used to verify and contrast the two algorithms.In the simulation,the influences of some assumptions such as the calibration mixer reciprocity and the measured mixer unidirectional model were deeply studied and analyzed.Finally,the measurement methods of the embedded local oscillator mixer and the two-way frequency conversion link were studied,and the feasibility of the measurement method was verified.Based on the traditional calibration method of vector network analyzer,this paper completes the theoretical derivation and experimental verification of vector calibration algorithm of mixer and compare the two methods.Finally,the precise conversion loss and group delay characteristics of the frequency-converter device and the chain are obtained by the calibration algorithm.