【摘要】：頻譜分析儀是頻域測(cè)量中用途最廣,使用量最大的一類測(cè)量?jī)x器。超外差式結(jié)構(gòu)是頻譜分析儀設(shè)計(jì)中采用的主要結(jié)構(gòu),它決定了頻譜分析儀射頻模塊的整體結(jié)構(gòu)方案,而射頻模塊是實(shí)現(xiàn)頻譜儀設(shè)計(jì)的關(guān)鍵技術(shù)之一,它的很多關(guān)鍵性能指標(biāo)對(duì)頻譜分析儀的整機(jī)性能有著重要影響。本論文主要實(shí)現(xiàn)經(jīng)濟(jì)型、高性能和結(jié)構(gòu)簡(jiǎn)單型的頻譜儀射頻模塊的設(shè)計(jì)。論文首先介紹了頻譜儀射頻模塊設(shè)計(jì)的國(guó)內(nèi)外現(xiàn)狀,分析了射頻模塊的關(guān)鍵技術(shù)指標(biāo)及其相互關(guān)系和影響因素。通過對(duì)指標(biāo)和技術(shù)難題分析,設(shè)計(jì)了實(shí)現(xiàn)3GHz頻譜分析儀射頻模塊的三級(jí)變頻外差式結(jié)構(gòu),確定了射頻模塊主要由三大模塊組成:射頻通道鏈路模塊、本振頻率合成源模塊和控制電路模塊。射頻通道鏈路模塊主要包括兩級(jí)程控衰減模塊、低噪聲放大模塊、三級(jí)變頻模塊(第一級(jí)變頻采用高中頻方案)和濾波器選頻模塊組成。并對(duì)噪聲系數(shù)、增益進(jìn)行了分析,用ADS2008中的BUGET工具對(duì)整個(gè)鏈路進(jìn)行了預(yù)算仿真,并利用HFSS和IE3D電磁波仿真軟件,對(duì)射頻模塊中的關(guān)鍵微帶濾波器進(jìn)行了設(shè)計(jì)和仿真。本振合成源模塊主要實(shí)現(xiàn)4.1357GHz~7.1357GHz的掃頻源設(shè)計(jì)和固定頻率的二三本振源設(shè)計(jì),并結(jié)合功率補(bǔ)償電路和濾波電路實(shí)現(xiàn)對(duì)本振信號(hào)的調(diào)理,以達(dá)到設(shè)計(jì)的指標(biāo)要求。掃頻源主要采用PLL芯片加高性能VCO實(shí)現(xiàn),比采用YTO更節(jié)約成本和空間�？刂颇K采用DSP+FPGA的結(jié)構(gòu),SPI四線數(shù)據(jù)傳輸方式,實(shí)現(xiàn)對(duì)掃頻源和其它程控芯片的控制,從而實(shí)現(xiàn)整個(gè)射頻模塊的功能。最后論文完成了射頻模塊硬件電路的設(shè)計(jì)及調(diào)試,并對(duì)本振源信號(hào),第三中頻輸出信號(hào)10.7MHz進(jìn)行了相關(guān)指標(biāo)的測(cè)試。結(jié)果表明本設(shè)計(jì)的射頻模塊方案實(shí)現(xiàn)了要求的指標(biāo)及功能需求。
[Abstract]:Spectrum analyzer is one of the most widely used and widely used measurement instruments in frequency domain. The superheterodyne structure is the main structure used in the design of the spectrum analyzer. It determines the overall structure of the RF module of the spectrum analyzer, and the RF module is one of the key technologies to realize the design of the spectrum analyzer. Many of its key performance indicators have an important impact on the overall performance of the spectrum analyzer. This paper mainly realizes the design of RF module of economic, high performance and simple structure. Firstly, this paper introduces the current situation of RF module design at home and abroad, and analyzes the key technical indexes of RF module, its relationship and influencing factors. Based on the analysis of indexes and technical problems, the three-stage heterodyne structure of RF module of 3GHz spectrum analyzer is designed. The RF module is mainly composed of three modules: RF channel link module. The local oscillator frequency synthesizer module and the control circuit module. The radio frequency channel link module mainly includes two stage program control attenuation module, low noise amplifier module, three stage frequency conversion module (the first stage frequency conversion adopts high frequency scheme) and filter frequency selecting module. The noise coefficient and gain are analyzed, the budget of the whole link is simulated with BUGET tool in ADS2008, and the key microstrip filter in RF module is designed and simulated by HFSS and IE3D electromagnetic wave simulation software. The local oscillator synthesizer module mainly realizes the design of 4.1357GHz~7.1357GHz frequency sweep source and fixed frequency local oscillator, and combines the power compensation circuit and filter circuit to adjust the local oscillator signal in order to meet the design requirements. The sweep frequency source is mainly realized by PLL chip and high performance VCO, which saves more cost and space than using YTO. The control module adopts the structure of DSP FPGA and the four-wire data transmission mode of SPI to realize the control of the frequency sweep source and other program-controlled chips so as to realize the function of the whole RF module. Finally, the hardware circuit of RF module is designed and debugged, and the local oscillator source signal and the third intermediate frequency output signal 10.7MHz are tested. The results show that the proposed RF module has achieved the required targets and functional requirements.
【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】：2014
【分類號(hào)】：TM935.21

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相關(guān)碩士學(xué)位論文 前1條

1 劉榮庭;3GHz頻譜分析儀射頻通道設(shè)計(jì)[D];電子科技大學(xué);2013年

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本文編號(hào)：2348643