本文選題：鎖相環(huán) + 超短波接收機(jī)　； 參考：《大連海事大學(xué)》2014年碩士論文

【摘要】：近年來,隨著社會(huì)需求的日益增長(zhǎng),無線通信技術(shù)已發(fā)展成為信息行業(yè)中最為耀眼的明星,而超短波技術(shù)作為其重要分支,不再僅限于專業(yè)范疇的應(yīng)用,而是廣泛延伸到各個(gè)領(lǐng)域中,如軍事、交通、醫(yī)療及漁業(yè)等。 本文的主要研究?jī)?nèi)容是基于27.5MHz～39.5MHz頻段調(diào)頻接收機(jī)的前端電路的研究與設(shè)計(jì)。在綜合比較多種方案后,最終選擇了超外差兩次混頻結(jié)構(gòu),該結(jié)構(gòu)主要包括前置濾波器、自動(dòng)增益控制(AGC)放大器、混頻器、鎖相環(huán)(PLL)頻率合成器和調(diào)頻解調(diào)電路等幾個(gè)部分,其特點(diǎn)是易于實(shí)現(xiàn)系統(tǒng)的高靈敏度和大動(dòng)態(tài)范圍。其中,鎖相環(huán)頻率合成器電路主要是用于產(chǎn)生接收機(jī)中的本振信號(hào)。根據(jù)設(shè)計(jì)方案,本文著重對(duì)各結(jié)構(gòu)模塊進(jìn)行了深入研究,并設(shè)計(jì)構(gòu)建了符合設(shè)計(jì)要求的超短波接收機(jī)的硬件平臺(tái)系統(tǒng)。此系統(tǒng)首先對(duì)天線接收到的射頻信號(hào)進(jìn)行濾波、放大和兩次混頻處理,再通過正交鑒頻器進(jìn)行解調(diào),最后輸出音頻信號(hào)。 本文首先就課題的背景和接收機(jī)的現(xiàn)狀進(jìn)行了闡述；其次對(duì)接收機(jī)的相關(guān)性能指標(biāo)進(jìn)行了詳細(xì)分析,其中包括有靈敏度、線性度、噪聲系數(shù)等；隨后具體討論了硬件電路的設(shè)計(jì),主要有鎖相環(huán)頻率合成器、前置濾波器、自動(dòng)增益控制電路、混頻器、窄帶調(diào)頻電路等模塊,并同時(shí)給出各模塊的原理圖以及部分電路的仿真圖；最后就系統(tǒng)硬件進(jìn)行了測(cè)試,并對(duì)測(cè)試中遇到的問題及測(cè)試結(jié)果進(jìn)行了分析。測(cè)試結(jié)果顯示：所設(shè)計(jì)的系統(tǒng),其指標(biāo)基本符合設(shè)計(jì)要求。
[Abstract]:In recent years, with the increasing demand of society, wireless communication technology has developed into the most dazzling star in the information industry, and ultrashort wave technology, as an important branch of it, is no longer limited to professional applications. It extends to a wide range of areas, such as military, transportation, medical and fishing. The main research content of this paper is the research and design of front-end circuit based on 27.5MHz~39.5MHz frequency modulation receiver. After a comprehensive comparison of various schemes, the superheterodyne twice mixing structure is finally selected. The structure mainly includes prefilter, automatic gain control (AGC) amplifier, mixer, PLL frequency synthesizer and frequency modulation demodulation circuit, etc. Its characteristic is that it is easy to realize the high sensitivity and large dynamic range of the system. The PLL frequency synthesizer is mainly used to generate the local oscillator signal in the receiver. According to the design scheme, this paper focuses on the in-depth study of each structural module, and designs and constructs the hardware platform system of ultrashort wave receiver which meets the design requirements. In this system, the RF signals received by the antenna are first filtered, amplified and mixed twice, then demodulated by a quadrature frequency discriminator, and finally the audio signal is output. In this paper, the background of the subject and the current situation of the receiver are described, and then the performance of the receiver is analyzed in detail, including sensitivity, linearity, noise coefficient and so on. Then, the design of hardware circuit is discussed in detail, including phase-locked loop frequency synthesizer, prefilter, automatic gain control circuit, mixer, narrowband frequency modulation circuit and so on. At the same time, the schematic diagram of each module and the simulation diagram of some circuits are given. Finally, the hardware of the system is tested, and the problems encountered in the test and the test results are analyzed. The test results show that: the system designed, its index is basically in line with the design requirements.
【學(xué)位授予單位】：大連海事大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TN858

【參考文獻(xiàn)】

相關(guān)期刊論文 前9條

1 吳建斌;田茂;;基于AD603的時(shí)變?cè)鲆娣糯笃鞯膶?shí)現(xiàn)[J];電子測(cè)量技術(shù);2008年04期

2 徐禮哲;;消除零中頻接收機(jī)直流偏移的分析和研究[J];電子技術(shù);2010年09期

3 李錚;沈泊;;一種新的有效抑制相位噪聲的載波恢復(fù)環(huán)路[J];復(fù)旦學(xué)報(bào)(自然科學(xué)版);2006年01期

4 李春劍;吉望西;劉達(dá)倫;;基于DDS橢圓型低通濾波器的設(shè)計(jì)[J];國(guó)外電子測(cè)量技術(shù);2009年01期

5 賈曉斌;劉四新;賈海亮;;基于DDS的橢圓函數(shù)低通濾波器的設(shè)計(jì)[J];電子設(shè)計(jì)工程;2010年09期

6 崔琳;用MC3371/MC3372設(shè)計(jì)的濾波器[J];國(guó)外電子元器件;2001年08期

7 宋里瑾;;接收機(jī)線性動(dòng)態(tài)范圍的分析與設(shè)計(jì)[J];科學(xué)技術(shù)與工程;2009年06期

8 楊道田;;關(guān)于接收機(jī)的相位噪聲[J];中國(guó)無線電;2006年10期

9 宋牧襄;超外差電路的發(fā)明人——愛德文·H·阿姆斯特朗[J];中國(guó)工程師;1995年04期

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