【摘要】：調(diào)頻連續(xù)波(FMCW)雷達(dá)與脈沖雷達(dá)相比具備以下優(yōu)點(diǎn):高距離分辨力、不存在距離盲區(qū)、時(shí)寬帶寬積大、結(jié)構(gòu)簡單、體積小、成本低等,所以在汽車防撞雷達(dá)、交通監(jiān)測(cè)系統(tǒng)、微波探礦等方面具有廣泛應(yīng)用。但是,連續(xù)波體制雷達(dá)的收發(fā)信號(hào)泄漏問題,導(dǎo)致其作用距離有限,制約了它的進(jìn)一步發(fā)展。針對(duì)FMCW雷達(dá)收發(fā)信號(hào)泄漏這一突出問題,本文采用數(shù)字式射頻對(duì)消的方法,降低FMCW雷達(dá)發(fā)射信號(hào)對(duì)接收通道的影響。本文的主要工作是設(shè)計(jì)一部步進(jìn)頻雷達(dá),包括鎖相源、發(fā)射鏈路、接收鏈路、數(shù)據(jù)采集部分,然后將射頻對(duì)消技術(shù)應(yīng)用于該步進(jìn)頻雷達(dá)。本文首先介紹了該課題的研究背景、國內(nèi)外的研究情況以及研究意義,對(duì)連續(xù)波雷達(dá)存在的問題進(jìn)行了簡單的分析,總結(jié)了當(dāng)前用來減小發(fā)射機(jī)信號(hào)泄漏對(duì)接收機(jī)的影響的方法,其中著重介紹了本系統(tǒng)中用到的射頻對(duì)消技術(shù)的原理和實(shí)現(xiàn)方法。在此基礎(chǔ)上,設(shè)計(jì)了數(shù)字式射頻對(duì)消方案。數(shù)字式射頻對(duì)消過程分為采樣、計(jì)算和控制三個(gè)過程,通過對(duì)參考信號(hào)和泄漏信號(hào)的采樣分析,將其幅值和相位進(jìn)行比對(duì),進(jìn)一步計(jì)算出控制矢量調(diào)制器所需要的控制電壓值,輸出至數(shù)模轉(zhuǎn)換器完成對(duì)矢量調(diào)制器的控制,形成與泄漏信號(hào)大小相等、相位相反的對(duì)消信號(hào),在接收鏈路實(shí)現(xiàn)對(duì)消。經(jīng)過對(duì)硬件系統(tǒng)的調(diào)試和分析,完成了該對(duì)消實(shí)驗(yàn),實(shí)現(xiàn)了對(duì)射頻對(duì)消模塊的精確控制。實(shí)驗(yàn)的測(cè)試結(jié)果為:從1.8GHz到2.2GHz的400MHz帶寬內(nèi),對(duì)消比達(dá)到30dB以上。最后總結(jié)了論文取得的成果和結(jié)論以及存在的問題。
[Abstract]:Compared with pulse radar, FM CW (FMCW) radar has the following advantages: high range resolution, no range blind area, large time-bandwidth product, simple structure, small volume, low cost, etc. So in automobile collision avoidance radar and traffic monitoring system, it has the advantages of high range resolution, no range blind area, large time-bandwidth product, simple structure, small volume and low cost, etc. Microwave prospecting is widely used. However, the leakage of received and received signals in CW radar restricts its further development due to its limited operating range. In this paper, the digital radio frequency cancellation method is used to reduce the influence of FMCW radar transmitted signal on the receiving channel in order to solve the problem of FMCW radar signal leakage. The main work of this paper is to design a step-frequency radar, including phase-locked source, transmitting link, receiving link, data acquisition part, and then apply radio frequency cancellation technology to this step-frequency radar. Firstly, this paper introduces the research background, the domestic and international research situation and the significance of the research, and simply analyzes the problems existing in CW radar. The current methods to reduce the influence of transmitter signal leakage on the receiver are summarized. The principle and implementation method of RF cancellation technology used in this system are emphatically introduced. On this basis, a digital RF cancellation scheme is designed. The digital RF cancellation process is divided into three processes: sampling, calculation and control. Through the sampling and analysis of the reference signal and the leakage signal, the amplitude and phase of the digital RF cancellation process are compared, and the control voltage value required for the control vector modulator is further calculated. Output to the digital-to-analog converter to complete the control of the vector modulator, the formation of the same size as the leakage signal, phase opposite cancellation signal, on the receiving link to achieve cancellation. After debugging and analyzing the hardware system, the cancellation experiment is completed, and the accurate control of RF cancellation module is realized. The experimental results are as follows: within the 400MHz bandwidth from 1.8GHz to 2.2GHz, the cancellation ratio is higher than 30dB. Finally, the paper summarizes the results and conclusions of the paper, as well as the existing problems.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TN958

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 朱澤坤;無人機(jī)通信干擾系統(tǒng)前端研究[D];電子科技大學(xué);2018年

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本文編號(hào)：2433900