摘要超宽带冲击雷达的信号带宽很宽,拥有高距离分辨率,其最早运用于军事领域,目前广泛应用于雷达探测、成像、精确定位、目标识别等技术中。与传统的“窄带”和普通的“宽带”技术相比,其主要区别在于信号带宽上。与常规窄带雷达系统相比,其优越性能体现在:抗干扰性能强、兼有低频和宽频的特点、具有极高的距离分辨力、具有良好的目标识别能力、具有超近程探测能力。42476
传统的产生超宽带雷达信号的方法主要包括直接数字波形合成法,利用高速模拟开关器件,结合脉冲整形网络产生脉冲波形,以及利用晶体管的雪崩效应等。由于上述方法对于硬件的要求都比较高,为了降低硬件标准,同时又能产生要求的脉冲信号,本文提出了通过低频方波组合叠加的方法产生发射波形,使其频谱向窄脉冲逼近,进而在时域波形上逼近窄脉冲串。最后分析叠加产生波形的测距性能。
关键词 超宽带;频谱;方波叠加;测距性能
毕业论文设计说明书外文摘要
Title Ultra-wideband impulse radar transmitter waveform generation and Ranging Techniques
Abstract
Ultra-wideband radar signal bandwidth is very wide, with high range resolution, which was first used in the military field, now widely used in radar, imaging, precise positioning, target recognition and other technologies. Compared with the traditional "narrowband" and ordinary "broadband" technology, the main difference lies in the signal bandwidth. Compared with conventional narrow-band radar system, its advantages can be reflected in: anti-jamming performance, both broadband and low frequency characteristics, with a high range resolution, it has a good ability to identify targets, with ultra-short-range detection capability.
The traditional method of ultra-wideband radar signal generation include direct digital waveform synthesis, high-speed analog switching devices, combined with the pulse shaping network generates a pulse waveform and use the avalanche effect transistor and the like. Due to relatively high hardware requirements described above, in order to reduce hardware standards, while generating a pulse signal, this paper presents a low-frequency square wave superposition method of generating transmit waveform to make it’s spectrum approach to the narrow pulse, and then close to the narrow bursts in the time domain waveform. Finally analysis ranging performance of the signal.
Keywords: Ultra-Wideband;Spectrum;Square wave superposition;Ranging performance
目录
1 绪论 1
1.1 课题研究背景 1
1.2 超宽带雷达的发展概况 1
1.3 超宽带技术的特点 2
1.4 超宽带技术的应用 3
1.5 本文的主要研究内容及章节安排 3
2 超宽带技术概论 4
2.1 超宽带技术原理 4
2.2 超宽带信号调制方式 4
2.2.1 脉位调制(PPM) 4
2.2.2 脉幅调制(PAM) 5
2.2.3 正交多载波调制(OFDM) 5
2.3 超宽带信号的接收 5
3 超宽带信号的产生技术 7
3.1 基于半导体器件的开关特性