Research On MIMO Channel Models Based On Ray Tracing Technique

The MIMO technology is considered as one of the most promising breakthroughtechnology in modern mobile communication system. It is an important approach to improvesystem performance, channel capacity and spectrum efficiency.In this thesis, the SBR/image method is selected to build an indoor MIMO channel modelon the basis of the MIMO channel characteristics, and the model is simulated with Matlab.Since the research on applying the SBR/image approach to MIMO channel modeling is notwide enough, we make an in-depth study of every step in this algorithm and modifies thealgorithm in order that it can be applicable to MIMO channel model. Specific modificationsinclude the establishment of a reflecting surface priority list, which can significantly reduce thenumber of test times of the intersection of ray tubes and object surface and save thecomputation time of the program, and application of a new intersection test approach, whichcan ensure any ray tube that makes contribute to the receiving points, and improve the accuracyof the field strength prediction. Furthermore, the modified SBR/image approach is applied inspecific indoor environment to verify its correctness and effectiveness.In addition, we make an intensive study of indoor MIMO channel on the basis of themodified SBR/image approach, including the study of channel capacity, such as the impact ofSNR and antenna distance on channel capacity, and the comparison of channel capacity in LOSand NLOS environments. Last but not least, some important parameters of MIMO channels aresimulated and calculated, such as power, delay spread, AOA and DOA, to analyze the signaldecline rule in the propagation, so that indoor short-range communications can be betterstudied.