通信信号调制识别与参数估计

发布时间：2018-01-15 22:12

本文关键词：通信信号调制识别与参数估计　出处：《西安电子科技大学》2014年硕士论文　论文类型：学位论文

【摘要】：本文主要研究了通信信号调制类型识别及参数估计的方法。通信信号的调制识别有着重要的应用,广泛应用于信号确认、干扰辨识、无线电侦听、电子对抗和信号监测等领域。在复杂电磁环境下估计通信信号特征参数并进行调制类型识别是现代电子战的重要任务之一。本文首先分析了各种常见通信信号的产生方式,在它们时域表达式的基础之上分析它们的瞬时特征,并对各个瞬时特征进行了仿真。接着基于这些瞬时特征介绍了基于决策论方法的调制类型识别算法,该算法通过定义四个特征参数对模拟调制信号进行识别;通过定义五个特征参数对数字调制类型进行识别。仿真结果表明随着信噪比的提高,不同调制类型信号的相应特征参数有着明显的差异,因此能很好的区分不同的调制方式。然后在对信号的调制类型没有任何先验信息的前提下,介绍了模拟与数字调制类型的混合识别算法,该算法通过九个特征参数来对接收到的信号进行识别,仿真结果表明,在信噪比大于15dB后,大部分调制类型的识别率都可以达到90%左右。因此基于决策论的调制类型识别算法是有效的。此外还应用高阶累积量算法对数字调制方式进行了识别,结果表明,该算法和基于决策论的数字调制识别算法相比能更有效的识别数字调制方式。文中还对通信信号的其它重要参数进行了估计,这些参数包括载波频率、码元速率、信噪比、非线性相位,这些参数在对截获信号进行识别和解调时是必不可少的,文中详细分析了各个参数的估计方法,并结合仿真结果分析了各种算法的优缺点。计算机仿真结果表明了本文所研究的各个算法的有效性。
[Abstract]:This paper mainly studies the methods of modulation type identification and parameter estimation of communication signal. Modulation recognition of communication signal has important applications, which is widely used in signal confirmation, interference identification, radio listening. In the field of electronic countermeasure and signal monitoring, estimating the characteristic parameters of communication signal and identifying modulation type in complex electromagnetic environment is an important part of modern electronic warfare. Firstly, this paper analyzes the characteristics of various common communication signals. The way it was produced. On the basis of their temporal expressions, their instantaneous features are analyzed, and each instantaneous feature is simulated. Then, based on these instantaneous features, the modulation type recognition algorithm based on decision theory is introduced. In this algorithm, four characteristic parameters are defined to identify the analog modulation signal. The digital modulation types are identified by defining five characteristic parameters. The simulation results show that with the increase of SNR, the corresponding characteristic parameters of different modulation types have obvious differences. Therefore, we can distinguish different modulation methods well. Then we introduce the hybrid recognition algorithm of analog and digital modulation types without any prior information about the modulation types of signals. The algorithm uses nine characteristic parameters to recognize the received signal. The simulation results show that the SNR is greater than 15dB. The recognition rate of most modulation types can reach about 90%, so the modulation type recognition algorithm based on decision theory is effective. In addition, high-order cumulant algorithm is used to identify the digital modulation mode. The results show that the algorithm can identify the digital modulation more effectively than the digital modulation recognition algorithm based on decision theory. The other important parameters of the communication signal are estimated in this paper. These parameters include carrier frequency, symbol rate, signal-to-noise ratio and nonlinear phase. These parameters are essential for the identification and demodulation of intercepted signals. In this paper, the estimation methods of each parameter are analyzed in detail. Combined with the simulation results, the advantages and disadvantages of various algorithms are analyzed. The computer simulation results show the effectiveness of the algorithms studied in this paper.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN911.3

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