Research On Spectrum Measurement And Amplitude Probability Distribution Analysis Of Electric Railway Pantograph And Catenaries' Offline Noise

The safety of the communication systems used in railway is very important, and it impacts on the efficiency of railway transport, security and development. In this paper, the author studies on electric railway pantograph and catenaries' offline noise spectrum measurement and amplitude probability distribution (APD) analysis and the interference with communication systems, such as GSM-R.The main study on electric railway pantograph and catenaries is its system designing, improvement and offline test, but less on its noise Electromagnetic Interference, only some about qualitative research focusing on the noise spectrum component analysis and the spatial distribution of electric Field based on experiment.The traditional methods can not analyze the spectrum of discharge process in pantograph and catenaries' offline spark and the amplitude-time change process. As a short time and wide scope of the spectrum, the traditional swept spectrum analysis equipment can't capture the full spectrum to accurately analyze it.The traditional measurement equipments almost measure the peak value, quasi-peak, average or RMS, but all these measurement methods don't apply to evaluate the quality of GSM-R system.In light of the inadequacies of the present research situation, this paper will discuss real-time and full-band spectrum measurement method utilizing real-time spectrum analysis equipments in detail, and will study APD method and the interference by electric railway with GSM-R system.The first chapter describes the interference of pantograph and catenaries' offline noise with the communication systems used in railway, analyses the EMI situation of China's railway GSM-R system.In Chapter 2, based on the characteristics of pantograph and catenaries' offline, a noise model of pantograph and catenaries' offline was established to illustrate the interference with the electric equipment inside the train box.The third chapter details the theory of APD, the bit error rate (BER) of GSM-R using MATLAB simulation, and the relativity between BER and APD. In the last of this part gives a VHDL design of a high-speed digital APD measurement system.In Chapter 4, the author studies the real-time spectrum tester and uses it by VBScript programs to construct an automated testing platform giving the APD test result of GSM-R.The last Chapter summarizes the conclusions of the experience and harvest of the research process, and points the direction of the further study.The paper consists of five chapters, including 28 figures, and 29 references.