Simulation Of Time Shift Non-Orthogonal Multi-Modulation Technology On Real Wireless Channel

Along with the fast development of the communications technology, digital modulation techniques are widely used. Orthogonal Frequency Division Multiplexing (OFDM) techniques become a top research project in this domain. However, due to wireless channel has variability and doppler frequency shift, it make OFDM orthogonality that between subcarriers are easily damaged, so that system performance greatly degrade.Professor Dequn Liang brought forward the Time Shift Non-Orthogonal Multi-Modulation Technology (TS-NMT) not only inherited the frequency division multiplexing principles, but also breaks through the limitation of orthogonality, which makes it can arrange more sub-channel under the same bandwidth and each sub-channel can have more sub-carriers than OFDM, thus greatly improving the information transmission rate and spectrum efficiency. At the same time, it bring two technical advantages:TS-NMT not like OFDM that sensitive to the frequency deviation., and also reduce the Peak-to-Average Ratio. Because human social life are growing demand for communication and urgent need for a better modulation, so the appearance of TS-NMT is catered to the needs of the development of wireless communications.Currently, Under the leadship of Professor Dequn Liang, Many simulation researches had been completed, including simulation on the wired, wireless, mobile, satellite channle, and made experiments on the physical channel, which proved its feasibility and superiority. However, our study also has a gap, not do the experiments on the real wireless channel, and TS-NMT has a more broad market prospects in the wireless communication. Therefore, the purpose of this thesis is do simulation study in the measured wireless channel and compare to OFDM modulation technique to prove its superiority and to lay the foundation for future practical appplocations.In this thesis, introduced the basic principle of TS-NMT, and do system simulation respectively in the theoretical and practical channel. In the simulation of theoretical channle, based on channel estimation algorithm made by previous graduate, this thesis presents a algorithm of direct measurement channel, which insert impulse signal in the send signal. In the simulation of practical wireless channle, this thesis first describes the method of how to measure channel, and in order to simulate the wireless channel's time-varying characteristics, it is necessary to measure sets of data and change channel at intervals of five yards in the simulation. Then, compare TS-NMT and OFDM system performance in the same condition, results show the advantages of TS-NMT. Lastly, convert MATLAB program into C language program, in order to provide technical support to simulation algorithm transplant to DSP.