Research And Implementation Of Wireless Fading Channel Simulation

Wireless channel is one of the core contents in the whole wireless communication system. Duing to the unexpected high costs, poor test repeatability and the sensitivity to climate conditions during channel environment outfield testing, various channel emulators are consequently essential to overcome the disadvantages mentioned above and simulate all kinds of typical wireless channel environment in laboratory.With the technical background of simulation and testing for multi-standard broadband wireless communication, this thesis devotes to some related theories and implementation algorithms of wireless channel simulation technology. The simulation of multipath fading channel based on DSP(Digital Signal Processing) platform is introduced in detail.Firstly, the main characteristic of wireless mobile channel is studied. Several principles and their simulation of fading channel are then illustrated on basis of Rayleigh channel model, Rice channel model, Gaussian channel model, and multipath delay as well. The detailed implementation algorithms are derived.Secondly, the system architecture of the wireless fading channel simulation is constructed, and the function module design is accordingly presented. Those function modules include multi-standard signal, multipath delay, Rayleigh fading, Rice fading, Gaussian channel, etc. Lots of simulating researches, which involving multi-standard signal generation, multipath delay algorithm of channel simulation, production and statistical property analysis for Rayleigh and Rician fading factors, and generation algorithm of Gaussian white noise, are described respectively. Furthermore, the structure, function and development environment of the key component, which is known as TMS320C6416 TGLZ, are provided. All the preceding simulating schemes and algorithms are accomplished via this signal processor. Finally, the thesis focuses on the integrated system realization. The vectogram of baseband QPSK signal, which has been propagated through the emulated fading channel, is measured by spectrum analyzer; meanwhile, the same emulated fading channel is verified through MatLab. By means of comparison, the feasibility of channel simulation proposed by this thesis can be eventually testified.It is shown that by use of theoretical analysis, simulation and experimental verification, the thesis finally implements channel simulation of wireless fading both in algorithm and hardware aspects. The outcome tested and verified by the spectrum analyzer and other instruments proves that the results meet the requirements of the project indicators.