【作者】 胡建波；

【导师】 张春杰；

【作者基本信息】 哈尔滨工程大学 ， 通信与信息系统， 2011， 硕士

【摘要】 现代电子战场的电磁环境越来越复杂多变,电子战信号的主要特点是频带宽、待处理信号密集、对非合作信号进行被动侦察和接收,因此对电子侦察设备提出了更高的要求。传统的电子战侦察接收机往往采用模拟接收方式实现,其参数温漂大、电路线性差,很容易导致信号的频率和相位等精细信息的丢失,因此使得数字接收机的发展成为研制新型电子侦察设备的必然趋势。随着新型雷达设备的不断出现,雷达信号形式也变得多种多样,为了适应复杂的信号环境,要求电子战接收机具有瞬时带宽宽、灵敏度高、动态范围大、能够截获同时到达的信号,以及具有对信号进行实时处理的能力。在这种新形势下,数字信道化接收机已经成为宽带电子侦察接收机的主要发展方向。本文首先介绍了课题的应用背景及意义、国内外发展现状和数字接收机的基本理论,包括信号采样理论、多速率信号处理理论和数字下变频原理。在对上述理论研究的基础上,提出了一种实信号的少混叠无盲区的信道化划分方法,并推导建立了实信号信道化接收机的数学模型。通过MATLAB进行仿真验证,结果证明了该数学模型的正确性。在信道化后续信号处理过程中,利用基于协调旋转数字计算机(CORDIC)算法实现了对信号包络和瞬时相位的提取,并采用一阶相位差分算法实现了瞬时频率的测量,对测频精度进行了讨论。在系统实现方面,根据数字信道化接收机的技术指标要求,采用国家半导体公司生产的高速ADC08D1000和ALTERA公司生产的FPGA芯片设计并实现了一套数字信道化接收机。同时在硬件平台上对系统各项功能和技术指标进行了详细测试,并对测试结果进行了分析,提出了一些改进意见。更多还原

【Abstract】 In modern Electronic Warfare, the electromagnetic environment is increasingly complicated. The main characteristics of the signal frequency bandwidth, the signal intensity to be processed, passive non-cooperative signal detection receiver, and therefore a higher electronic reconnaissance equipment requirements. The tranditonal radar receiver adopts analog receiving mode, which has large temperature drift, worse linear circuit and easily lead to signal frequency and phase information is losted. So the development of digital receiver has become a trend. With the rapid development of technology on radar, the receiver,which is used in the electronic warfare, is required to have a broad instant frequency band, a high sensitivity and a broad dynamic range, to be able to detect multiple signals arrived simultaneously, and to have Real-time processing capacity as well. The digital channelized receiver has become the main development direction for research of wideband digital receiver.This paper first introduces the topic of the application background, development status at home and abroad, and the basic theory of digital receiver, such as the technique of sample, multirate signal processing, digital down converter, is introduced. A less-overlap non-blindzone channelized method was proposed and a channelized digital receiver mathematic model for real signal was established based on the research of the above theory. The simulation results from MATLAB show that the method has the capability of whole probability intercept and capture to broad band signal and testifie the receiver mathematic model as well. In respect of channelized subsequent processing, the CORDIC algorithm was adopted to extract signal envelope and instantaneous phase and the phase difference algorithm was adopted to realize instantaneous frequency measurement. The computer simulations experiments were done, the performances analysed deeply.In respect of system implementation, according to specification requirements of channelized receiver, the high-speed ADC08D1000 of National Semiconductor and the FPGA of ALTERA were adopted to realize a set of digital channelized receiver. The various functions and technical specifications were tested and analyzed in detail at the hardware platform and some improved suggestions were proposed.更多还原