Adaptive And Mechanism Analyses Of OFDM Communication Technology To Doppler Frequency Shift

In wireless communication systems, the high-speed information transmission rate is one of what people wanted, in the actual application, the family of Orthogonal Frequency Division Multiplexing (OFDM) technique are widely used with its excellent performance of anti-multipath and Doppler frequency shift of the resistance. In high dynamic communication scenario, due to the Doppler frequency shift (DFS) result form relative motion, the communication between the client machine (or machine and base station) will be affected inevitably. Doppler frequency shift not only will result in synchronous deviation in receiver,but also generated time selective fading at the same time, this will seriously affect the wireless communication system, especially the performance of the broadband wireless communication systemunder under high dynamic communication scene. At present, the Doppler frequency shift inhibiting technology research is the hotspot, Doppler frequency shift correction technique and time selective fading suppression research relatively mature.In this paper, the family of OFDM, namely Orthogonal Frequency Division Multiplexing technology based on the Quadrature Amplitude Modulation (OFDM/QAM), Orthogonal Frequency Division Multiplexing based on Offset Quadrature Amplitude Modulation(OFDM/OQAM) and Fractional Fourier Orthogonal Frequency Division Multiplexing technique (FrFT-OFDM), are the research objects, studies the three kinds of OFDM technology adaptability of the doppler shift, and tries to analyze the mechanism.The remaining sections are organized as follows:Firstly, provide the basic principles of the family of OFDM (OFDM/QAM,OFDM/OQAM and FrFT-OFDM), and profile the modeling method of wireless channel, the information model of OFDM family technology is also given under white gaussian noise(AWGN) channelSecondly, set up the simulation model of OFDM family technology under the Doppler frequency shift channel, and write the MATLAB program, and analyzes the three kinds of DFS adaptability of OFDM technology.Finally, tries to analyze the mechanism of impact the DFS action to the three kinds of OFDM technology (OFDM/QAM and OFDM/OQAM, FrFT-OFDM), and corresponding validation of simulation is given.