| The growth in demand for information and the limited spectrum resources of available are in the conflict. Thus the requirements of the next generation of communication systems must have higher spectrum efficiency to meet rapidly growing demand in communication capacity. MIMO (Multiple Input Multiple Output) technology can significantly improve the system spectrum efficiency, transmission efficiency and performance. In the future it will have good prospects in wireless communication systems. Continuous phase modulation (CPM) improves the properties of spectral density by smoothing the transition phase between symbols. It is a mode of good performance, and is one of the main modulation modes of a variety of new mobile communication and wireless radio. In this thesis, based on the basic principle of MIMO and CPM, a number of key technologies of MIMO-CPM systems are in-depth investigated from theoretical aspects.The impact of wireless channel is a key factor in a mathematical model and algorithm design of transmission system. Based on the existing theoretical results, the modeling method of the non-linear and correlated channel is given. It starts from the spatial correlation, and then uses the classic Jakes model to generate the fading signals in combination with the characteristics of non-linear power amplifier. A generating method of the coefficient matrix of a non-linear and correlated MIMO fading is proposed. On the other hand, the performance characteristics are analyzed, of 2- antenna orthogonal space-time coded CPM (OST-CPM) system for maximum likelihood sequence detection algorithm (MLSD) in the non-linear and corrected MIMO channel. The impact of channel correlation on the OST-CPM system is similar with that on space-time coding combined with a linear modulation mode. It will lead to performance degradation of MLSD algorithm for OST-CPM system, but have the same diversity gain, and can attain full diversity gain. When the nonlinear distortion exists, a pre-distortion circuit is applied to compensate the impact of non-linear power amplifier on the MLSD algorithm of OST-CPM systems. There is little effect of non-linear power amplifier on encoding performance of non-coherent detection algorithm for OST-CPM system, due to the characteristic of constant envelope of CPM signals. This is one of the main advantages of MIMO-CPM systems than multi-antenna systems combined with linear modulation modes.Another key technology MIMO-CPM system is the issue of space-time encoding and decoding. In this paper, two design methods of space-time coded CPM systems are proposed, based on Rimoldi decomposition of CPM signals. And the space-time coding could be Zp- domained convolutional coding and space-time trellis coding. Both the joint coded CPM systems are applicable not only to RC and REC shaped full response CPM signals, but also to partial response CPM signals. The overall encoding system could be quite simple through joint coding design of the space-time coding and CPE module of CPM signals. Although the performance of the STC-2RC-CPM system is slightly worse than that of the STC-1RC-CPM system, the STC-2RC-CPM system will have wider application prospects in the actual communication systems, due to higher spectrum efficiency of partial response CPM signals. An improved non-coherent detection algorithm for OST-CPM system is proposed, which is mainly applied to RC and REC shaped full response CPM signals. The performance of the non-coherent detection algorithm is slightly worse than that of the MLSD algorithm over quasi-static fading channels. However the non-coherent algorithm does not need to know the channel state information, it has more practical values. In fast Rayleigh fading channels, when the length of observation window increases, the performance of the non-coherent detection algorithm degrades rapidly, which is the application limitations of this algorithm.Synchronization is the basis of the receiver of communication systems. Two symbol timing estimation algorithms are proposed, based on different forms of training sequences. The two symbol timing synchronization algorithms do not depend on the specific types of space-time codes, thus it is applied to MIMO-CPM systems of any space-time coding combined with CPM signals. The second method has a simpler structure, less computational complexity, a broader range of applications and better estimation performance than the first method. The frame error rate (FER) performance of space-time trellis coded CPM (STTC-CPM) system decreases a little in case of non-ideal synchronization when the second timing algorithm is employed. However, when the fading rate increases, the mean-square error performance of the second method gradually decreased. Consequently this algorithm does not apply to the Rayleigh fast fading channels.
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