| Wireless communication is currently one of the most active research topics. It is one of the key issues needing urgent solution to improve the spectrum efficiency and increase system capacities under satisfying the quality of service in wireless communication field. Multiple Input Multiple Output (MIMO) technology is an important milestone in this filed in recent years. It can effectively take advantage of the random fading from the multipath channel by exploiting space resources, and has a huge potential of reducing bit error rate and increasing the capacity without increasing the total emission power and system bandwidths. MIMO technology has become one of the chief technologies for high-speed wireless communications in the future.The achievement of the superiority of MIMO communication depends on the performance of the channel model a lot. However, channel modeling is traditionally a difficult part in the research of wireless communications. So it is of great significance to investigate relatively simple but effective channel modeling methods on the basis of understanding the critical characteristics of the multiple-antenna channel.Firstly, the characteristics, fading and dispersion effects of the indoor wireless channel are introduced. Based on them, two kinds of MIMO channel modeling methods are emphatically introduced, which are the non-physical model based on statistical characteristics and the physical model based on scattering characteristics. According to the classification, several typical indoor multiple-antenna channel models are reviewed respectively.Secondly, based on the power correlation matrix channel modeling method, the simulation of indoor multiple-antenna channel is divided into two parts, which are the simulation of spatial correlation mapping matrix and the simulation of flat fading channel transmission matrix. The spatial correlation mapping matrix for indoor channel is obtained based on the truncated Laplacian power azimuth spectrum. The theoretical foundation of Jakes simulator modified by inserting a random phase shift is introduced in detail, and the transmission matrix of a flat fading channel with two transmitting antennas and two receiving antennas(2×2) are simulated by Matlab programming. The simulation results show that the probability density function of the fading channel amplitudes is subject to the Rayleigh distribution with standard deviation of1, and the phases submit to the uniform distribution well. A simulation flow for indoor multiple-antenna flat fading channels is summarized, and the simulation method for the frequency selective fading channel is briefly introduced. Based on the simulation results of indoor2x2channel, changing regularities of the space selective fading characteristic and spatial correlation are analyzed, and the influence of antenna configurations on the distribution characteristics of instantaneous channel capacity is investigated. How angular parameters affect the average channel capacity is also analyzed.Thirdly, channel measurements are carried out with two transmitting antennas and one receiving antenna (2×1) in a typical laboratory environment based on the time-domain measuring platform with high sampling rates. Propagation characteristics such as path loss, time-delay spread parameters and their influencing factors, signal correlation and so on are statistically analyzed.Finally, a conclusion on this thesis is given. Deficiencies are discussed and the next to do is also proposed. |
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