Research And Verification Of Jitter Characteristics Of Clock Signals Under Modulation And Crosstalk

Clock signal is an important component of communication and electronic system,and its stability can be characterized by time domain jitter and frequency domain phase noise.When the clock signal is interfered by modulation and crosstalk,its stability will be directly affected.Therefore,the performance evaluation of clock signal has become an important research content in the field of electronics and communication.In this thesis,the jitter characteristics of clock signals under modulation and crosstalk are modeled and analyzed theoretically,and a jitter test system is designed to test these two signals,so as to verify the correctness of the theoretical model.The main research contents of this thesis are as follows:1.Based on the time-frequency domain energy conversion theory,the jitter formula of the clock signal under the modulation noise(PM/FM/AM)is deeply studied,and the correctness of the model is verified by Matlab simulation theoretically.2.Based on the scattering parameter model,the transmission model of the circuit network is derived by impedance matching,interpolation and zero complement,and the jitter measurement method of the clock signal under crosstalk noise is proposed.At the same time,the Vector Network Analyzer is used to test the S-parameter of a specific circuit,and it is imported into the Matlab software to generate a clock signal with crosstalk noise.Finally,the peak-to-peak jitter is obtained by calculating the multi-period time of the signal rising edge along the zero crossing.3.Based on “ADC+FPGA” architecture,the phase noise and jitter testing system is designed and implemented.The system includes signal conditioning module,data acquisition module,data processing module and algorithm module.The whole system uses FPGA as the main control chip to receive the digital signal sampled by ADC,and uses phase demodulation and spectrum estimation algorithm to process and cache the signal.Finally,the calculation results of phase noise spectrum and jitter are displayed.In order to verify the correctness of the system,Agilent E5052 B signal source analyzer was compared with the system,which laid a foundation for testing and verifying the jitter evaluation model of clock signal under modulation and crosstalk.4.The jitter evaluation model of clock signal under modulation and crosstalk is tested and verified.For modulation,the oscilloscope is compared with the test system designed in this thesis to verify the accuracy of the model.For crosstalk,oscilloscope test is used to verify the accuracy of the jitter test method in this thesis.