GMSK跳频信号参数盲估计和盲检测算法的研究

【作者】 赵俊；

【导师】 陈文正；

【作者基本信息】 浙江大学 ， 通信与信息系统， 2003， 硕士

【摘要】 跳频技术是扩频技术的一种，是80年代以来出现的一种新颖的通信方式。跳频通信具有良好的抗干扰性，低截获概率及组网能力，因此跳频技术的一出现，便在军事领域得到了极大的发展，采用跳频技术的短波电台在军事通信中得到了广泛应用，极大地提高了军事装备的抗截获和抗干扰能力，向通信对抗提出了严峻的挑战。开展对跳频通信对抗的研究，寻求截获，分选识别跳频通信信号方法，已成了当前通信对抗领域紧迫而困难的任务之一。 近几年来，现代信号处理的三大热点——谱估计、高阶统计量方法、时频分析等理论和技术日臻成熟和完善，逐渐被应用到通信对抗领域，使得目前通信对抗信号处理技术的研究达到了一个高潮。 目前，运用常规的通信对抗技术已经无法对跳频电台起到真正有效的对抗作用，因此，应用现代信号处理技术，研究对跳频信号的盲侦收、处理新算法，已经成了目前通信对抗领域的一大研究热点。由于跳频信号的时变特性以及时频分析技术在分析时变非平稳信号方面的强大功能，因此，如何应用时频分析技术来处理跳频通信信号，是目前跳频信号侦收算法研究领域的一大方向。本文的工作正是在这一领域所做的一种探索。 第一章介绍了短波通信和短波跳频电台在军事领域中的广泛应用，以及现代信号处理技术特别是时频分析技术对促进跳频通信对抗研究的重要意义。 第二章介绍了跳频通信以及GMSK调制的基本原理，在Matlab Simulink环境下给出了基于GMSK方式的跳频短波发射机仿真模型。 第三章用“平滑伪WVD(SPWVD)”时频分析技术分别研究了对高速跳和低速跳的跳频信号的参数盲估计算法，并对这两种算法，分别在Matlab的环境下做了仿真和性能分析。 第四章对用多跳自相关技术做跳频信号盲检测以及用特征矩阵联合对角化技术(JADE)做跳频信号盲分离的算法做了研究和仿真。更多还原

【Abstract】 Frequency-Hopping (FH) is a novel spread spectrum communication technique,which develops very fast in military field due to its LPI/LPD (Low Probability of Intercept / Detection) properties and immunity against interferences,The extensive application of HF (high frequency) frequency-hopping radios in military has greatly enhanced the ability of military equipments against jamming and interception and brought up a new austere challenge for communication countermeasures. So researching the surveillance,interception and classification methods for FH signals has been a difficult and pressing task in communication countermeasure fields.In recent years,the three hot-points of Modern Signal Processing theory - Spectrum Estimation,Higher Order Cumulants,Time-Frequency Analysis have become more and more mature and greatly promoted the research work for communication countermeasure techniques.Nowadays,the research of new surveillance and interception algorithms for FH signals using modern signals processing technique has become a hot topic since the conventional communication countermeasure techniques don’t work any more. FH signals are time-variant and non-stationary signals,while time-frequency analysis is a powerful tool to analyze this kind of signals. So how to deal with FH signals using time-frequency analysis technique is a important aspect in the research fields of FH surveillance algorithms. In this paper we will do some efforts in this field.Chapter 1 introduces the extensive application of HF/VHF communication and HF/VHF radios in military field,and points out the significance for promoting the research work of FH communication countermeasure using modern signal processing techniques,especially time-frequency analysis.Chapter 2 introduces the theory of frequency-hopping and OMSK,at the same time gives out a FH-GMSK radio model in High Frequency band under the MATLAB simulink environment.Chapter 3 respectively proposes the parameter blind estimation algorithms for high-speed-hop and low-speed-hop FH signals based on Smoothed Pseudo WVD (SPWVD) . Furthermore,the simulation results are given to demonstrate the algorithms performance.Chapter 4 gives out the blind detection algorithm of unknown FH signal using Multi-Hop Autocorrelation technique and blind signal separation algorithm using Joint Approximate Diagonalisation of Eigen-matrices (JADE) technique. Some elementary simulation results are also presented here.更多还原