Design And Implementation Of YTO Control Module In The Spectrum Analyzer

The spectrum analyzer is a very important class of electronic measuringinstruments, so it is essential in the research and production in the field of modernmobile communication, radio, television, electronic countermeasures, radar navigation,and wireless spectrum detection. In order to meet the needs of test and measurement inthe field of domestic high-end applications, the spectrum analyzer requires a wide rangeof analysis, test speed, high measurement accuracy advantages. Local oscillator of theRF front-end scanning control module is the key control part of the spectrum analyzermachine and directly determines the merits of the performance of the instrument.Therefore, the design of local oscillator control module in the spectrum analyzer has thevery high value.According to the mature3GHz spectrum analysis technology of single band, thethesis researches the design and implementation of YTO control module, which isbackgrounded by the research and development of8GHz radio spectrum analysismodule. According to the hysteresis impact on broadband scanning of YTO, it mainlydesigns the control module of fast frequency hopping, compensation module of thenonlinear scanning and control module of multi-band scanning, so as to realize theoverall design goals. The research content of this thesis mainly includes the followingthree aspects. Firstly, it designs and implements the YTO control module of fastfrequency hopping. The thesis researches inherent hysteresis, eddy current and phaselock loop characteristics of YTO, and analyzes the time factor affected YTO frequencyhopping. According to the tuning influence of the filtering large capacitor of thefrequency hopping preset time in the actual circuit, it presents a switch control programof large capacitor, and finally completes the design of switch control circuit, the testprocess and result analysis. Secondly, it designs and implements the YTO controlmodule of nonlinear scanning compensation. Firstly, the thesis describes theapproximate frequency offset curve with MATLAB, through the scanning experiment ofthe frequency offset data. Secondly, it gives the compensation program and validationfrom scanning time, initial scanning frequency and scanning step according to analyzing the frequency offset factors and laws in scanning YTO. Finally, it integrally completesthe nonlinear scanning compensation algorithm of YTO and validation analysis. Thirdly,it designs and implements the YTO control module of multi-band scanning. It mainlycompletes the program design of sub-band scanning, simulation and verification for themain components function of control module, and finally gives the test result and someof the solution to the problem which meets in design process.The thesis finally completes the overall design goals of YTO control module. Thefrequency hopping time reduce from50ms to less than30ms under the control of thefast frequency hopping control module. The scanning frequency deviation falls on thelocking range±10MHz of PLL under the control of nonlinear compensation controlmodule of YTO scanning. It realizes the scanning control of seven ranges according tothe whole scanning ranges.