Mimo Wireless Channel Modeling And Simulation Studies

MIMO (Multiple Input Multiple Output) is one of the most important key technologies used for improving data rate in new wireless communication systems, such as wireless access network and mobile systems.MIMO research is based on MIMO channel modeling and simulating. Channel model is used to simulate and evaluate the performance of base-band algorithms, and also we need channel model to help in multi-antenna design. So, more realistic and simpler MIMO channel models are always needed to be studied.This paper researched on MIMO channel modeling and simulation based on spatial correlation. The influence of spatial parameters and antenna structure to spatial correlation was particularly analyzed, and the correlation expresstion was deduced. The main work of this paper is detailed as follows.Firstly, we introduced the development and application of MIMO technology, summarized the fruit of MIMO channel modeling. And then we analyzed and simulated the channel capacity of SIMO,MISO and MIMO systems, which completely proved that MIMO wireless communication could significantly improve channel capacity.Secondly, we summarized the characteristics of wireless fading, analyzed the time delay,the Doppler spectrum and the angle spread. Based on the characteristics of time-field and frequency-field, we studied the SISO channel modeling. Analyzed the channel simulation method based on Clarke model. And we used one efficient simulation model to generate Rayleigh channel. Result shows that the simulation model we used has a good performance.Thirdly, spatial correlation between MIMO antennas was analyzed and deduced. And we used this closed expression in full and direction antennas,we deduced the expression of spatial correlation when the azimuth spread is uniform or Laplacian. And we used Bessel function to simplify the correlation expression. We simulated spatial correlation with different azimuth spread,power azimuth spectrum,angle of arrival and antenna distance. And also we simulated the MIMO channel capacity with different spatial correlation, which shows that MIMO channel capacity was influenced greatly by correlation.Fourthly,we presented a stochastic MIMO channel model based on spatial correlation. A detailed simulation flow was designed and the performance of this model was analyzed. In addition, the influence of polarization factors were deeply researched and induced into the correlation-based MIMO channel model.Fifthly, the structure of MIMO system incorporated with smart antennas was considered. We analyzed the spatial correlation between smart antenna beams and then a special MIMO antenna structure incorporated with smart antennas was presented to reduce correlation in MIMO system.