基于循环卷积的六边形多载波传输技术的研究与实现

发布时间：2018-06-25 15:03

本文选题：CHMT系统 + PAPR优化　；参考：《大连海事大学》2017年硕士论文

【摘要】：随着移动通信技术应用的越来越广泛,对该技术的要求也越来越高,其所面临的最大挑战就是双选择信道带来的干扰。六边形多载波传输技术(Hexagonal Multi-carrier Transmission,HMCT)可以很好的抵抗双选择信道带来的载波间干扰(Inter Carrier Interference,ICI)和符号间干扰(Inter Symbol Interference,ISI),但是由于六边形多载波传输系统的成型脉冲长度一般不小于4倍的符号长度,并且该系统的成型脉冲采用了线性移位的方式,导致时域信号长度过长从而降低了频谱效率。此外HMCT系统还面临严峻的峰均功率比(Peak to Average Power Ratio,PAPR)问题。针对上述问题,本文提出了一种针对双选择信道基于循环卷积的六边形多载波传输技术(Circular-Convolution Hexagonal Multicarrier Transmission,CHMT)。CHMT系统的成型脉冲采用了循环卷积的方式,可以控制时域信号的长度,有效的抑制了峰均功率比,并且CHMT系统综合考虑了时频(Time-Frequency,T-F)空间内的网格参数,使得CHMT系统可以更好的抵抗双选择信道带来的影响。在此基础上,又设计实现了一种基于FFT(Fast Fourier Transform)变换的快速算法,极大的降低了系统复杂度,并且在不同信道环境下对CHMT系统进行了性能仿真,验证CHMT系统在双选择信道下具有良好的性能。其次,研究了多载波通信系统PAPR的优化方法,将这些方法应用到CHMT系统中,使得CHMT系统获得更好的PAPR性能。最后在3L Diamond软件无线电平台上结合DSP模块和FPGA模块实现了CHMT系统基带信号的调制与解调功能,设计显示模块绘制出CHMT/HMCT系统基带信号的实时动态波形图,通过编程控制SMT911射频前端实现了 CHMT系统基带信号的发送功能。
[Abstract]:With the increasing application of mobile communication technology, the requirement of this technology is becoming higher and higher. The biggest challenge it faces is the interference brought by the dual selection channel. Hexagonal Multi-Carrier Transmission (HMCT) can resist inter carrier interference (ICI) and inter symbol interference (ISI), but the pulse length of hexagonal multi-carrier transmission system is not small. More than four times the length of the symbol, Moreover, the shaping pulse of the system is linearly shifted, which results in long time domain signal length and reduced spectral efficiency. In addition, HMCT system also faces the severe problem of Peak to Average Power ratio (PAPR). In order to solve the above problems, this paper presents a circular convolution method to control the length of time domain signals in a circular convolution-based hexagonal multi-carrier transmission (CHMT) system based on circular convolution. The peak-to-average power ratio (PAPR) is effectively suppressed, and the time-frequency (T-F) space mesh parameters are taken into account in the CHMT system, so that the CHMT system can better resist the influence of the dual-channel. On this basis, a fast algorithm based on FFT (Fast Fourier transform) is designed and implemented, which greatly reduces the complexity of the system and simulates the performance of CHMT system in different channel environments. It is verified that CHMT system has good performance in dual selection channel. Secondly, the optimization methods of PAPR in multi-carrier communication system are studied, and these methods are applied to CHMT system to make the system achieve better PAPR performance. Finally, the modulation and demodulation function of the baseband signal of CHMT system is realized by combining DSP module and FPGA module on 3L Diamond software radio platform. The display module is designed to draw the real-time dynamic waveform diagram of the baseband signal of CHMT / HMCT system. The base band signal transmission function of CHMT system is realized by programming SMT911 RF front end.
【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN929.5

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