The Research And Implementation On The Circular-convolution Based Hexagonal Multicarrier Transmission Technology

As the application of mobile communication technology more and more widely,the requirement of this technology is also getting higher,the biggest challenge in the mobile communication technology is the interference caused by the double selective channel.HMCT(Hexagonal Multi-carrier Transmission)system has a better performance in resisting ICI(Inter Carrier Interference)and ISI(Inter Signal Interference)which caused by the double selective channel,however,because the length of shaping pulse is not less four times than the length of symbol,and the shaping pulse is linear-shift,so it will cause too long length of signal in time domain,and lower the spectrum efficiency.Moreover,HMCT system is facing a severe PAPR(Peak to Average Power Ratio)problem.For the above problems,this paper proposed a CHMT(Circular-Convolution Hexagonal Multicarrier Transmission)system for double selective channel.The shaping pulse of CHMT uses a circular-convolution algorithm,which can control the length of the signal in time domain,so the CHMT system has a better PAPR performance,while considering grid parameter of T-F(Time-Frequency)space to make the CHMT system has a better performance in double selective channels.On this basis,this paper design and achieve a fast algorithm based on the FFT(Fast Fourier Transform)transform,lower the complexity of the CHMT system.And the performance of CHMT system is simulated under different channel conditions,it is verified that the CHMT system has a better performance under the double selective channel.Then study the method of optimizing PAPR in multi-carrier communication system,and applies these methods to CHMT system,which makes CHMT system get a better PAPR performance.Finally,by using DSP module and FPGA module on the 3 L Diamond platform to achieve the function of modulation and demodulation of baseband signal,design the display module to draw the real-time dynamic signal waveform of HMCT/CHMT baseband signal,by programming to control the SMT911 RF front end to achieve the process of sending out the CHMT baseband signal.