The Research And Realization On The Hardware-in-the-loop Simulation Technology Of The Wireless Network Of High-speed Railway

Recently, the high speed railway is developing rapidly. The reliability and validity of the mobile communication system is very strict under high speed condition. The research on the mobile communication system of high speed railway has become a hot area these years. Usually, the research method combines the theory analysis, performance measurement and simulation.At present, the testing, analysis and research on the wireless network performance mainly rely on the drive-test. Nevertheless, there are some limitations of drive-test including the low flexibility and repeatability. If the test needs to be done repeatedly, the cost is quite large. Besides, there are many factors which influence the network performance. Since drive-test is limited by the actual environment, it’s hard to take the test under certain condition. Too many variables have a bad influence on the theoretical analysis.The simulation on mobile communication system usually utilizes the computer to realize. But the computer simulation is just an approximate method with lower reliability. It can’t imitate the complicate and varied wireless propagation environment precisely. The paper focuses on a hardware-in-the-loop simulation method which utilizes the radio channel emulator and the actual equipments of GSM-R system to construct the hardware-in-the-loop simulation system. Therefore, the simulation system is more reliable and authentic with flexibility and repeatability. The simulation on the communication system under different conditions can provide the environment for both the performance testing and the theoretical research.Base on the analysis above, the innovation of this paper is illustrated in the following points:Firstly, the thesis utilizes the radio channel emulator and the GSM-R system equipment to construct the hardware-in-the-loop simulation system. The simulation system is the same with the actual GSM-R system except the wireless link is simulated by the radio channel emulator so that the simulation system is more reliable.Secondly, by using the actual measured signal level data, the thesis reappear the wireless network of Beijing-Shanghai high speed railway and realize the hardware-in-the-loop simulation of the wireless network of whole line. The performance of the system is evaluated and analyzed under different speeds. Thirdly, the thesis gets the channel impulse response matrix from the radio channel emulator. Using the frequency shift feature of signal, the thesis realizes the dynamic simulation on the Doppler shift of high speed railway.