【作者】 吕超；

【导师】 林云；

【作者基本信息】 哈尔滨工程大学 ， 信息与通信工程， 2016， 硕士

【摘要】 在电子战领域中,接收带宽内信号的信道化分离是提高侦察效果的关键技术之一。信道化技术可以增加接收机的侦察带宽,提高侦察信号的测频、测相精度,对一定频段内的信号实现有效的分离,以便后续的信号调制方式的识别、信号参数的估计等操作。本论文主要研究了在接收带宽内存在多个窄带、宽带混合信号且频谱情况可变化情况下信号的动态信道化提取方法。论文首先研究了均匀信道化技术的实现方案,分析了减少混叠和盲区需要降低原形滤波器带宽增加系统资源消耗的不足,提出了以频率响应屏蔽技术为基础的改进方案,在性能不降低的条件下改进方案有效减少了计算量。根据多通道分析滤波器组将信号划分到不同的子带,满足重构条件的综合滤波器组可将子带信号重构恢复的特性。当接收范围内某个子信号覆盖其中一定数量的子带时,对相应的子带进行重构可恢复出该信号。对整个接收带宽内的信号进行子带分解,再分别对不同频率范围的子带信号分别重构,可实现信号的非均匀信道化提取。为了获得系统信道化分的先验信息,本文研究了基于信号功率谱估计的频谱检测方法,并研究了窗函数及信号重叠率对检测性能的影响。结合信号频谱检测和信号的非均匀信道化提取方法,本文给出了动态信道化的实现方案,并对信号的重构函数接口进行标准化法封装。经仿真验证,该方法可以有效的实现对不同频域分布上的信号的分离,并对频谱变化进行自适应调整。最后本论文对给出的动态信道化方案在基于软件通信体系结构(SCA)架构软件无线电平台上进行了工程实现。详细给出了设计在FPGA中预处理、频谱检测、子带分解等部分的实现与验证。并使用C++语言编写了上位机的数据提取程序,子信号重构程序,人机交互界面的程序。设计了利用大气FM广播信号与信号发生器共同生成测试信号的测试方案,验证了动态信道化方案的可行性。更多还原

【Abstract】 In the field of communication reconnaissance, effective separation of the received signal is one of the key technologies to improve the effect of electronic warfare. Channelized receiver could increase the bandwidth of the reconnaissance receiver in radar signal detection,and improve the measurement accuracy of frequency and phase. Channelized technology could also separate signals effectively within different frequency band for modulation identification and parameter estimation.This thesis mainly studies dynamic changes channelized extraction method under the situation of multiple narrowband, broadband, mixed signal existing in the receiver frequency band and the frequency distribution changing randomly. Firstly, the uniform channelized technology implementation scheme was studied, its shortcomings was also analyzed. An improved algorithm was presented using the method of frequency response masking.Compared with traditional structure, much amount of calculation is reduced. M channel filter bank reconstruction condition was studied. On this foundation, non-uniform channelized receiver model is given. In order to get the spectrum distribution of signal, the method of signal power spectrum estimation is used. The factor that influence its performance is also studied . When the blackman window function is used to intercept the signal, the performance will be better. Improving signal overlap rate can also improve the detection performance,however when overlap rate of 1/3, the performance of ascension is not clear..Modulation filter banks are further studied in the paper, especially the factor of reconstruction of broadband signal from several sub-channels. In this paper, the data interface of reconstruction function of signal is set in common. Combined with the frequency spectrum of the signal detection, a realization structure of the dynamic channelized receiver is given. It has been verified by the simulation that the method can not only separate the signals effectively on different frequency distribution, but also adaptive adjustment according to the spectrum changes.Finally, a dynamic channelized scheme implementation realized on the software radio general SDR platform based on SCA architecture is given. The design parts in FPGA such as pretreatment, spectrum detection, subband decomposition, pcie are stated in detail and verified by modelsim. Using the c++ language, we wrote programs to extract data from FPGA,deal the effective signal and design the interface between system and human. Considering the limitation of test conditions in the lab, FM radio signals from atmosphere and chirp signal generated by AWG70001A are used to verify the feasibility of dynamic channel receiver.From the result, we get the conclusion that the design could extract signals with different frequency.更多还原