Research On Key Techonlogies Of MIMO-CPM System

Wireless communications are developing quickly with the demands of technology. Two challenges of wireless communication are the limited frequency source and complexity of channel enviorment. They are also the motivation, which push the technology forward. Continues Phase Modulation (CPM) is the most efficient modulation of power and bandwidth with single antenna. It is used widely in wireless communication such as GSM etc.. Multiple-Input and Multiple-Output (MIMO) can overcome the fading of channel and improve the channel capability. It is a hot problem of wireless communication.This paper takes several key problems of MIMO-CPM system to be settled. The author provided an Orthogonal-Like Space-Time Coder with CPM (OL-ST-CPM), which has a simplified decoding algorithm. Making use of assistant array, the author proposed a channel estimator with a back to zero training sequence which can be fit for most MIMO-CPM system. The author also provided a non-coherent demodulation algorithm for Orthogonal Space-Time Coder with partial response CPM(OST-PCPM) system. In this system, the Channel Information State(CSI) estimator is delimited.The main contents of this paper are as follows:The first charpter introducted the performance of CPM and MIMO system, aslo the status quo of main research in MIMO-CPM, then it listed the structure and the main contribution of this paper.The second charpter first provided system model of MIMO-CPM, then it analysed the performance of Trellis-Coded Space-Time of CPM system(TC-ST-CPM) and its decoding complexity. The author introduced a Orthogonal- Like Space-Time Coder of CPM (OL-ST-CPM)with four antennas and analysed the characters of OL-ST-CPM. The author provided an algorithm of OL-ST-CPM with arbitary antennas which could reduce the complexity of Viterbi algorithm of decoding distinctly. The author also analysed the Pair Wise Error Probability (PWEP) of OL-ST-CPM and proved the full rank character of the signal matrix. According to the linear modulation system, the author also provided the design rules of the OL-ST-CPM.The third charpter introduced some kind of wireless channel and channel estimator algorithm in MIMO system. Then the author proposed a channel estimation algorithm in flat Rayleigh fading channel. The algorithm proposed a back to zero training sequence, which could make the estimator fit for most MIMO-CPM system without phase jump. With analysis of simulation results, the author also proposed a estimate method of partial-Sample-Points coupled withα-REC shaping function which can resist Timing-Estimate Error of 2Ts and shorten the training sequence. The analysis showed that the log of Mean Square Error (MSE) for the estimator declined with bit signal to noise linearly.The fourth charpter introduced the character of Orthogonal Space Time Coder CPM(OST-CPM) with full and Orthogonal Space Time Coder with partial reponse CPM(OST-PCPM). With the analisis of non-coherent demodulation of full response OST-CPM, the author proposed a non-coherent demodulation for partial reponse OST-PCPM and provided a phase-feed back structure of ML estimtor. With the simulation results, the author set the parameters rightly for a economic system.