变换域通信系统设计、建模与仿真研究

【作者】 何智青；

【导师】 任辉；

【作者基本信息】 西北工业大学 ， 信号与信息处理， 2003， 硕士

【摘要】 本文主要研究了一种新型通信系统——变换域通信系统(TDCS)。国外对TDCS的研究已有数年的历史，在我国还尚未开展这方面的研究，本文是第一篇关于TDCS的研究论文。TDCS与传统通信系统的不同点是，首先TDCS通过信道估计在变换域设计信号波形，其次TDCS没有采用载波调制，而是用一个类似噪声的基函数进行信息调制。TDCS具有很强的抗干扰能力和较高的LPI(低截获概率)特性。本文首先介绍了TDCS的基本理论，分析和研究了TDCS的主要算法。为了有效的进行研究工作，开发了变换域通信系统动态和静态仿真平台以及TDCS—CDMA仿真平台。基于仿真平台，对比研究了基于FFT和基于DWT的TDCS的系统性能。针对目前TDCS理论不完善的特点，从理论上对TDCS做了一定的分析：具体分析证明了TDCS具有多址能力，推导出了TDCS在多址环境下的误码率公式，并在仿真试验中进行了验证；首次分析了收发端基函数不一致情况下TDCS的性能，给出了在此情况下的误码率公式，并在仿真实验中给以验证；初步分析了TDCS在多径传播环境下的性能；此外还对采用不同调制技术的TDCS做了仿真研究。本文的工作开创了国内有关TDCS的研究工作，部分研究结果与目前TDCS的研究结果相比较有新的发展，所完成的工作为今后对TDCS进一步的研究打下了良好的基础。更多还原

【Abstract】 In this paper, a new communication system-Transform Domain Communication System (TDCS) is researched. TDCS is a developmental system that has demonstrated interference avoidance capability. It is different from traditional communication systems at two points: 1) the communication waveform is designed in transform domain (frequency or scale) according to the estimation of electromagnetic environment, 2) no carrier modulation is employed, but a noise-like basis function is used to modulate the data. The work of the thesis is as follows. First, the basic theory of TDCS is introduced and the principal algorithms about TDCS are analyzed. A simulation platform including dynamic and static is designed in order to research the characteristics of TDCS. Two kinds of TDCS respectively based on FFT and DWT are studied using the platforms. A TDCS-CDMA simulation platform are also completed for researching the ability of multiple access and a formula about bit error rate (BER) of multiple access is proved. The performances of TDCS in the case of transmitter and receiver with different basis function are also analyzed and a formula as a result is presented. Additionally the performances of TDCS about multipath are simply discussed. The modulation technique is also investigated in this paper. Finally a large amounts of simulation experiments support above All research works . This paper is the exploring research of TDCS. The results having obtained in this paper provid a strong groundwork for the future research work of TDCS.更多还原