【摘要】：軍事上的需求促進(jìn)了雷達(dá)在理論和體制上的極大發(fā)展,除了應(yīng)用于軍事上外,雷達(dá)在空中交通管制中用于對飛機(jī)航路和終端區(qū)域的監(jiān)視,此外,雷達(dá)也廣泛用于民用上。脈沖壓縮雷達(dá)是一種新體制雷達(dá),它最重要的優(yōu)勢在于解決了作用距離、距離分辨率和速度分辨率之間相互矛盾的問題,同時(shí)具有良好的抗干擾性能。雷達(dá)波形的參數(shù)對雷達(dá)性能具有至關(guān)重要的作用,脈沖的持續(xù)時(shí)間關(guān)系到發(fā)射信號的能量和雷達(dá)的作用距離,在工作頻率確定的情況下速度分辨率與時(shí)寬成正比,而距離分辨率與信號帶寬成正比。因此通過控制發(fā)射波形的時(shí)寬和帶寬能夠同時(shí)獲得遠(yuǎn)作用距離、高距離分辨率和高速度分辨率。此外發(fā)射信號的相位噪聲、雜散和線性度等指標(biāo)也關(guān)系到雷達(dá)的信號檢測和處理。本文根據(jù)Ku波段脈沖雷達(dá)信號源的實(shí)現(xiàn)目標(biāo)和指標(biāo)要求,基于FPGA和DDS芯片AD9910設(shè)計(jì)并實(shí)現(xiàn)了VHF頻段的雷達(dá)信號源,主要產(chǎn)生了四類信號:(1)線性調(diào)頻波形;(2)相位編碼波形;(3)脈沖調(diào)制信號;(4)連續(xù)波。根據(jù)4位DDS波形控制碼和導(dǎo)前脈沖信號輸出14種模式的波形,并完成不同模式間的快速切換。波形的參數(shù)包括中心頻率、調(diào)頻帶寬和調(diào)頻脈寬等。本文從硬件和軟件兩個(gè)方面設(shè)計(jì)并實(shí)現(xiàn)了滿足指標(biāo)要求的雷達(dá)信號源。主要內(nèi)容如下:首先,概述了脈沖壓縮雷達(dá)系統(tǒng)和頻率源技術(shù)的發(fā)展現(xiàn)狀。然后,簡要介紹了脈沖壓縮雷達(dá)的基本原理和典型的四種脈沖壓縮波形,重點(diǎn)介紹了DDS的工作原理和特點(diǎn);介紹了雷達(dá)信號源關(guān)注的指標(biāo)以及基于PLL和DDS技術(shù)實(shí)現(xiàn)的常用技術(shù)。其次,根據(jù)指標(biāo)要求設(shè)計(jì)了模塊實(shí)現(xiàn)方案;合理選用DDS和FPGA等器件,給出了硬件電路的設(shè)計(jì)過程;詳細(xì)介紹了DDS控制器的FPGA實(shí)現(xiàn)。最后,完成了軟硬件的調(diào)試,給出了VHF雷達(dá)信號源的測試結(jié)果,分析了調(diào)試過程中的問題;給出了系統(tǒng)聯(lián)合測試結(jié)果,最終結(jié)果滿足指標(biāo)要求。
[Abstract]:Military requirements promote the great development of radar in theory and system. In addition to military applications, radar is used in air traffic control to monitor aircraft routes and terminal areas. In addition, radar is also widely used in civilian applications. Pulse compression radar is a new radar system. Its most important advantage is that it solves the contradiction among operating range, range resolution and velocity resolution, and has good anti-jamming performance at the same time. The parameters of radar waveform play an important role in radar performance. The duration of the pulse is related to the energy of the transmitted signal and the operating range of the radar. The velocity resolution is proportional to the time width when the working frequency is determined. The range resolution is proportional to the bandwidth of the signal. Therefore, long-range, high-range resolution and high-speed resolution can be obtained simultaneously by controlling the time width and bandwidth of the transmitted waveform. In addition, the phase noise, spurious and linearity of the transmitted signal are also related to the radar signal detection and processing. According to the target and target requirement of pulse radar signal source in Ku band, this paper designs and implements the radar signal source in VHF band based on FPGA and DDS chip AD9910, which mainly produces four kinds of signals: (1) LFM waveform; (2) phase coded waveform; (3) pulse modulated signal; (4) continuous wave. According to the 4-bit DDS waveform control code and the pre-pilot pulse signal, 14 modes of waveforms are outputted, and the fast switching between different modes is accomplished. The parameters of the waveform include the center frequency, frequency modulation bandwidth and frequency modulation pulse width. In this paper, a radar signal source is designed and implemented from the aspects of hardware and software. The main contents are as follows: firstly, the development of pulse compression radar system and frequency source technology is summarized. Then, the basic principle of pulse compression radar and four typical pulse compression waveforms are briefly introduced, especially the working principle and characteristics of DDS, and the concerned indexes of radar signal source and the commonly used techniques based on PLL and DDS technology are also introduced. Secondly, the realization scheme of the module is designed according to the requirement of the index; the design process of the hardware circuit is given with reasonable selection of DDS and FPGA, and the FPGA implementation of the DDS controller is introduced in detail. Finally, the hardware and software debugging is completed, the test results of VHF radar signal source are given, the problems in the debugging process are analyzed, and the joint test results of the system are given, and the final results meet the requirements of the target.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TN957.51

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1 陳文嬋;;AN/TPS-59戰(zhàn)術(shù)雷達(dá)[J];現(xiàn)代雷達(dá);1980年03期

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本文編號：2453534