Pci-based Broadband Shortwave Channel Simulator Design And Realization

In the short-wave communication engineering, people often need to test the performance of the short-wave communication equipment. If the tests are taken over the real short-wave channel, much time, manpower and money had to be cost, and it is impossible to have the same tested condition and channel environment. In addition, it is difficult to change the channel parameters by manmade. Consequently, the accuracy of simulators for test purpose becomes increasingly crucial. Especially wide band high frequency (WBHF) communication was developing with a high speed in the last decades, so the WBHF channel simulator weighs heavily in the applications.At present, short-wave channel simulator studies have become more sophisticated in foreign countries, but these simulators'target is audio signal, data-processing rate low, and expensive.The start time of the studies of short-wave channel simulator is much later in domestic, however, it have made some progress, but many of these simulators are based on DSP implementation for narrow-band HF channel. Wide band channel simulate requiries substantial high-speed parallel signal processing, and FPGA is more suitable than DSP in the aspect. The research goal of this paper is to realize a reconfigurable broadband shortwave channel simulator, whoes processing unit is FPGA.In the second chapter, the characteristics of short-wave channel and the typical short-wave channel models have been introduced, and ITS channel model was selected as the Implementation model of the simulator.In the third chapter, based on the goals of broadband, real-time and reconfigurable, a wide band channel simulator has been realized. First, the signal processing board was realized. It was based on industrial computer platform, and contains PCI interface, XC4VSX35 FPGA and RF interface, and can be used in real-time channel simulate. Secondly, the implementation and verification of channel simulate program of FPGA were made, and the program can process real-time signal of bandwidth of 30MHz, and the resolution of Doppler spectrum is 0.01455Hz. Finally, the control software and PCI driver were introduced. The PCI driver is based on the Windows Driver Model, and was developed by using Driver Works.In the fourth chapter, the channel simulator has been tested. Those experiments show that the simulator can simulates multipath-delay, Doppler frequency spread and shift, large-scale fading, AWGN channel, single frequency interference etc. Recommended parameter ranges and tested parameter values in several typical HF communication environments were provided, and the WBHF channel simulator was used to simulate those HF communication environments'small scale fading.The channel simulator, which was realized in this paper, can be used in Communications equipment testing, station construction, network planning and so on.