黃河科技學院畢業設計（文獻翻譯） 第14頁 壓控振蕩器（VCO）技術綜述1. 前言壓控振蕩器(voltage-controlled oscillator, VCO) 是一種以電壓輸入來用來控制振蕩頻率的電子振蕩電路,是現代無線電通信系統的重要組成部分課題。在當今集成電路向尺寸更小、頻率更高、功耗更少、價格更低發展的趨勢下，應用標準工藝設計生產高性能的壓控振蕩器已是射頻集成電路中的一個重要課題。環形振蕩器易于集成，可調頻率范圍大，但相位噪聲不如性能不如LC振蕩器。LC壓控振蕩器要求高品質因素的無源器件，需要片上電感和變容管器件才能集成集成。振蕩器自其誕生以來就一直在通信、電子、航海航空航天及醫學等領域扮演重要的角色，具有廣泛的用途。在無線電技術發展的初期，它就在發射機中用來產生高頻載波電壓，在超外差接收機中用作本機振蕩器，成為發射和接收設備的基本部件。隨著電子技術的迅速發展，振蕩器的用途也越來越廣泛，例如在無線電測量儀器中，它產生各種頻段的正弦信號電壓:在熱加工、熱處理、超聲波加工和某些醫療設備中，它產生大功率的高頻電能對負載加熱;某些電氣設備用振蕩器做成的無觸點開關進行控制;電子鐘和電子手表中采用頻率穩定度很高的振蕩電路作為定時部件等。尤其在通信系統電路中，壓控振蕩器(VCO)是其關鍵部件，特別是在鎖相環電路、時鐘恢復電路和頻率綜合器電路等更是重中之重，可以毫不夸張地說在電子通信技術領域，VCO幾乎與電流源和運放具有同等重要地位。2. 主題2.1 VCO的發展過程 上世紀初，Armstrong發明了電子管振蕩器，經Hartley改進電路設計并開發成功電子管VCO。電子管VCO的振蕩頻率是通過改變振蕩電路中電感器或電容器的參數值來進行調節。當時人們對電子管振蕩電路開展了大量的研究，今天仍在沿用的Hartley，Colpitts，Clapp，Armstrong，Pierce等經典振蕩電路結構，就是當時的研究成果。上世紀中葉，晶體管問世并很快取代電子管成為振蕩電路的有源器件。特別是變容二極管的應用對VCO的發展具有重要意義。變容二極管的電容隨外加電壓的改變而變化，用變容二極管作壓控器件，改變其控制電壓就可實現VCO振蕩頻率的調節。這樣，晶體管、變容二極管和其他無源元件就構成了分立式的晶體管VCO。這種晶體管VCO實現了振蕩頻率的電子調諧，這是變容二極管對VCO發展的重大貢獻。與電子管VCO相比較，晶體管VCO具有電子調諧、體積小、成本低、功耗小、質量好、調頻范圍設置簡便等優點。晶體管VCO的發展也是是電視技術能在當時迅速推廣的重要原因。1960年至1980年，晶體管VCO被電子系統設計所廣泛采用。到了1980年，情況發生了變化，混合集成的VCO組件和單片集成的VCO IC出現了。這兩種新技術對VC0的發展產生了重要的影響。VCO從此就開始步入現代VCO技術的發展時期。各種VCO技術的壽命期與時間的關系示于圖l。該圖簡要地說明了VCO技術在過去80多年里的發展歷程。圖1 各種VCO技術壽命期 變容二極管、電容器、電感器等元器件的小型化為制造VCO組件創造了條件。VCO組件是一種混合集成電路器件，具有封裝和外引線。雖然分立元件的晶體管VCO具有按用戶要求設計工作頻率和調諧范圍的靈活性，但一般在生產中都需要耗費大量的人工對確定頻率的元件進行調試，以消除元件誤差對頻率的影響。此外，分立元件VCO需要良好的屏蔽，其尺寸也比較大。分立元件的VCO已不能完全滿足現代無線電子系統發展的要求。20世紀80年代末、90年代初，移動電話迅速發展，對帶封裝的振蕩器組件的需求也日益增長。這為VCO組件的發展提供了難得的市場機遇。隨著新型無線應用領域的不斷發展，各VCO組件廠商開發了適合不同應用領域所需頻率的產品。由于表面安裝元件的不斷小型化(1206，0805，0603，0402和0201)，新開發的VCO組件的尺寸也越來越小，成本也越來越低。圖2說明了現代商用VCO組件尺寸隨時間減小的變化情況。目前，VCO組件達到了新的水平，其體積已減小到4 mm5mm2mm，大批量供貨VCO的銷售單價已降至1美元左右。VCO組件在15年中其尺寸急劇減小，滿足了蜂窩電話等新型無線移動裝置對小型化的要求。VCO組件體積變化過程圖2 20世紀90年代末期，出現了一種尺寸更小、成本更低的VCO技術，這就是單片集成VCO技術。單片集成VCO是一種半導體集成電路器件，其全部電路元件均集成在同一芯片上。這種器件像VCO組件一樣，是一個完整的VCO，具有封裝和外引線。首批單片集成VCO采用2英寸GaAs IC工藝和單片微波集成電路(MMIC)技術制造，是為衛星接收機和雷達系統研制的。其工作頻率高達數GHz，但成本高昂。大多數早期單片GaAs VCO的研究工作都是針對軍事應用展開的，很少涉及民用領域。在20世紀80年代，Si-IC技術還是一種低頻技術，不能為單片集成VCO提供上千兆赫茲的工作頻率和所需的帶寬。 經過研究與開發，1990年Si-IC技術在高頻化和無源元件集成方面獲得重大進展，開發成功工作頻率很高的晶體管、變容二極管和單片集成的高Q值電感器與高頻電容器。這為高頻硅單片集成VCO的研究與開發奠定了技術基礎。無線移動通信系統的發展，要求大批量提供成本低、體積小、工作在8002500MHz頻段的VCO。人們為此開展了大量的研究與開發工作。1992年，美國California大學首先報道了硅單片VCO IC的研究成果。其后，對硅單片VCO IC的研究進入繁榮期，采用不同技術方案的硅單片VCO IC相續問世。硅單片VCO IC由高頻雙極晶體管IC技術和SiCMOS-IC技術研制而成。在硅單片VCO IC的研制過程中，學術研究機構通常采用獲得廣泛應用的SiCMOS-IC技術，而工業界則采用RFIC專用的BiCMOS技術。硅單片集成VCO體積更小、成本更低并適合大批量生產的產品，而且可以采用RF收發前端的工藝技術進行制造。這表明，VCO可以與混頻器、低噪聲放大器、鎖相環等其他RF收發前端的功能電路模塊實現集成。正是由于VCO IC具備這些潛在的優勢，盡管早期產品性能欠佳，但人們對它的研究工作一直沒有停頓。通過不斷改進，其產品已廣泛應用于無繩電話、藍牙裝置、WLAN、GPS、DBS等無線裝置與系統之中。表1列出了一些單片集成VCO的應用實例。表1 含有單片集成VCO的商用RFIC實例目前，單片集成VCO還不能用于對相位噪聲要求很高的應用領域。像GSM、CDMA等具有高數據速率的移動電話系統，還只能使用VCO組件。2.2 VCO技術的發展趨勢今后，VCO技術的研究與開發工作將繼續圍繞VCO組件和單片集成VCO展開。但是，全集成單片VCO技術是研究工作的重點，也是未來VCO技的發展方向為了適應現代無線系統發展的要求，VCO組件不斷向小型、高頻、寬帶、高輸出化和特性多樣化方向發展。將采用新的超小型元件和更先進的薄膜技術與表面安裝技術，繼續推進VCO組件封裝的微型化和表面安裝化。通過晶體管的改進及振蕩電路的開發，解決好小型化帶來的諧振器Q值降低的問題和低功耗引起的特性劣化問題。第四代移動電話以及其他工作在微波頻段高端的無線系統需要VCO組件進一步提高工作頻率，實現VCO組件高頻化。開發工作頻率更高的微波VCO組件是未來十分重要的研究課題。SiGe BiCMOS等RF IC基礎工藝技術正在不斷發展與進步。半導體工藝制造有源器件與無源器件將具有更好的性能。現在，即使用Si工藝技術，也可制得 超過50GHZ的晶體管和高Q值，大電容變比，低串聯電阻的優質便容二極管。這類工藝技術還具有襯底損耗低，金屬化層厚，器件寄生元件少，工作頻率高，工作電流小的單片集成VCO。現代無線系統，尤其是現代無線移動通信系統，不僅要求VCO自身小型化和低成本化，而且希望VCO能同頻率合成器與收發機的其他單元電路進行單片集成，以達到減少整機體積和成本的目的。此外，單片集成VCO的設計理論也在深化，設計技術也越來越先進。差分放大器，幅度控制，二次諧波抑制器，IC耦合變壓器，復合振蕩器，高頻結構設計等技術正不斷被納入單片集成VCO的設計之中。利用單片集成VCO技術把優質VCO同收發機電路集成在一起的新產品不斷問世。例如在WLAN和藍牙裝置中，最新的收發機就把高質量的VCO同RF收發前端IC集成在一起，使其尺寸大大減小。 WLAN系統（2.4GHZ 802.11b型和5GHZ 802.11a型）要求VCO具有很低的相位噪聲。由于RF IC VCO技術的不斷發展，衛星接收機，CATV機頂盒，無線數據裝置，無繩電話，移動電話等商用RF系統與裝置越來越多地采用集成化頻率源。顯然，在大規模商業應用領域中，單片集成VCO占有的市場份額將不斷增大，而分立元件VCO和VCO組件占有市場將逐步減小。單片集成VCO在大規模商用無線系統中占主導地位的時代很快就會到來。VCO技術已經實現了從笨重的電電子管VCO電路到面積小于1平方毫米Si IC的跨越。3. 總結VCO是頻率源的關鍵器件，已廣泛應用于各種電子系統之中。VCO的性能對電子系統有決定性的影響。現代無線移動通信系統的發展促進VCO高頻化，形成了新一代微波VCO。VCO組件和單片集成VCO是微波VCO的主要結構形式，是目前無線系統采用的主流產品。雖然，在總體性能水平方面，單片集成VCO目前還不如VCO組件好，但它具有集成優勢，仍然是VCO未來發展的方向。在RF IC工藝技術中，SiGe BiCMOS技術是單片集成VCO最有前途的制造技術。來源于：ISO/IEC JTC1/SC29/WG1 (ITU-SG8) N2058, JPEG2000 is now an International Standard, 9 March 2001.附：英文原文voltage controlled oscillator 1 PrefaceVoltage controlled oscillator ( voltage-controlled oscillator, VCO ) is a kind of voltage input to control the oscillation frequency of the oscillating circuit, is a modern radio communication system is an important part of task 1 2. In the integrated circuit to the smaller size, less power consumption, higher frequency, lower price trends, application standard process design and production of high performance voltage controlled oscillator RF integrated circuit is an important subject in the. The ring oscillator is easy to be integrated, the adjustable frequency range, but better performance than LC oscillator phase noise. LC VCO requirements quality factors of passive devices, need the on-chip inductor and varactor devices to integrate 3.Oscillator since its birth has been in communication, electronics, aerospace and other fields of medicine navigation plays an important role, has a wide range of uses. In radio technology in the initial stage of development, it is in the transmitter to generate high frequency carrier wave voltage, the heterodyne receiver is used as a local oscillator, a transmitting and receiving equipment basic components. With the rapid development of electronic technology, the oscillator uses more and more widely, for example in radio measurement instruments, it produces various frequency sinusoidal signal voltage: in the heat processing, heat treatment, ultrasonic machining and some medical equipment, it produces high power high frequency electric power of load heating; some electrical equipment oscillator. The contactless switch control; electronic clock and electronic watches using frequency stability high oscillation circuit as a timing component. Especially in the communication system circuit, a voltage controlled oscillator ( VCO ) is one of the key parts, especially in the phase-locked loop circuit, clock recovery circuit and frequency synthesizer circuit is Chongzhongzhi is heavy, it is no exaggeration to say in electronic communication technology, VCO almost with the current source and the operational amplifier has the same important position.2.Theme2.1The development of 1.VCO processAt the beginning of the last century, Armstrong invented electronic oscillator, the improved Hartley circuit design and the successful development of VCO tube. Electronic tube VCO oscillation frequency is changed by the oscillation circuit inductor or capacitor parameter values to adjust. At that time the people to the electronic tube oscillation circuit to carry out a great deal of research, today is still in use in the Hartley, Colpitts, Clapp, Armstrong, Pierce and other classical oscillating circuit structure, was the research results.The middle of the last century, the first transistor and quickly replace the tube becomes oscillatory circuit of the active device. In particular the varactor applications on the VCO has important significance to the development of. Variable capacitance diode capacitance as a function of the applied voltage change, using varactor diode voltage controlled device, change the control voltage can be achieved VCO oscillation frequency regulation. In this way, the transistor, varactor diodes and other passive components form the vertical transistor VCO. This transistor VCO implementation of the oscillation frequency of the electronic tuning varactor diode, it is the significant contribution of VCO development. Electronic tube with VCO compared to VCO, transistor with electronic tuning, small volume, low cost, small power consumption, good quality, easy FM range setting. Transistor VCO is the development of television technology at that time rapid promotion of important reasons. From 1960 to1980, VCO transistors are widely used in electronic system design. By 1980, the situation has changed, hybrid integrated VCO module and monolithic integrated VCO IC appeared. These two kinds of new technology to the development of VC0has produced important influence. VCO has started to enter the modern VCO technology development period. A variety of VCO technology life cycle and the time relation shown in Figure L. The graph, a brief description of the VCO technology in the past 80 years development course.Fig 1 VCO technology life cycleVariable capacitance diodes, capacitors, inductors and other components of the miniaturization for the manufacture of VCO components to create the conditions. VCO component is a hybrid integrated circuit device, a package and the outer lead wires. Although discrete transistor VCO according to user requirements with the design and operating frequency tuning range and flexibility, but generally in the production need to consume a large amount of artificial to determine the frequency components for debugging, in order to eliminate the element error on the frequency effect. In addition, discrete components VCO needs good shielding, its size is relatively large. Discrete element VCO can not satisfy the requirements of the development of modern wireless electronic system.At the end of nineteen eighties, the early 90s, the rapid development of the mobile phone, with a package of oscillator components growing demand. This is a VCO component development offerred rare market opportunity. Along with the new wireless application development, each VCO component manufacturers developed for different applications in the field of desired frequency products. Due to the small surface mount components (1206080506030402 and0201), the new development of the VCO component size is more and more small, cost more and more low. Figure 2 illustrates the modern commercial VCO component size with reduced variation. At present, the VCO component has reached a new level, its volume is reduced to 4mm * 5mm * 2mm, supply large quantities VCO sales price has dropped to about $1. VCO component in the15 years of its size reduced sharply, to meet the new wireless mobile devices such as cellular phones on the miniaturization requirement.The VCO component volume change process of2Nineteen ninties stage, the emergence of a smaller size, lower cost of the VCO technology, which is monolithically integrated VCO technology. Monolithic integrated VCO is a semiconductor integrated circuit device, all the circuit components are integrated on the same chip. This device like the VCO module, is a complete VCO, with packaging and outer lead. The first batch of monolithic integrated VCO uses 2 inches of GaAs IC technology and the monolithic microwave integrated circuit ( MMIC ) manufacturing technology, is for the satellite receiver and radar system. Its high working frequency of GHz, but the high cost. Most of the early single GaAs VCO s research work is aimed at the military application of unfolding, rarely involved in civil field. In the nineteen eighties, Si-IC technology is a kind of low frequency technology, not for the monolithic integrated VCO with Giga Hertz frequency and bandwidth required for.Through research and development, in 1990 the Si-IC technique in high frequency and passive components integration has achieved significant progress, the successful development of the work with very high frequency transistor, variable capacitance diode and monolithic integration of high Q value of the inductor and the high frequency capacitor. The high frequency silicon monolithic integrated VCO research and development laid a technological basis. Wireless mobile communication system development, requirements in large quantities to provide low cost, small volume, work in the 800 2500MHz band VCO. It carried out a great deal of research and development work. In 1992, American California University was first reported by Silicon Monolithic VCO IC research. Thereafter, the silicon monolithic VCO IC research to enter prosperous period, using different techniques for Silicon Monolithic VCO IC continued publication.Silicon Monolithic VCO IC by high frequency bipolar transistor IC technology and SiCMOS-IC technology developed by. In Silicon Monolithic VCO IC development process, academic and research institutions usually adopt the widely used SiCMOS-IC technology, while the industry is using RFIC special BiCMOS technology. Silicon monolithic integrated VCO smaller volume, lower cost and suitable for mass production of products, but also can be used to RF front-end technology manufacturing. This shows, VCO can be associated with a mixer, low noise amplifier, phase locked loop and other RF front-end circuit function module to realize the integrated. It is because the VCO IC with these potential advantages, although early products of poor performance, but the research work has not stopped. Through continuous improvement, its products have been widely used in cordless phones, Bluetooth devices, WLAN, GPS, DBS and other wireless devices and systems. Table 1 lists some monolithic integrated VCO application examples 4.Table 1 contains monolithic integrated VCO RFIC commercial examplesAt present, monolithic integrated VCO also cannot be used for phase noise of demanding applications. Like GSM, CDMA has a high data rate mobile phone system, also can use VCO components2.2The development trend of 2.VCO TechnologyIn the future, VCO technology research and development work will continue to focus on VCO components and monolithic integrated VCO expansion. However, the monolithic integrated VCO technology is the research focus, but also the future of VCO technology development direction in order to adapt to modern wireless system development requirements, VCO components to small, high frequency, wide band, high output and characteristic development. We will adopt a new miniature components and more advanced thin film technology and surface mount technology, continue to promote the VCO package miniaturization and mounted on the surface of. The pass transistor oscillation circuit improvement and development, solve good miniaturization brings resonator Q reduces problems and low power consumption caused by deterioration of a problem. Fourth generation mobile phones and other work in the microwave band high-end wireless systems need to further improve the working frequency of the VCO component, VCO component high frequency. Development of frequency higher microwave VCO components are very important research topic in the future.SiGe BiCMOS RF IC basic technology is evolving with progress. Semiconductor manufacturing technology of active devices and passive components will have better performance. Now, using the Si technology, also can be used for more than 50GHZ transistors and high Q value, high capacitance ratio, low series resistance and capacitance diode quality. This technology also has a substrate of low loss, metal layer thickness of parasitic element, device is little, high working frequency, small working current monolithic integrated VCO.Modern wireless systems, especially in modern mobile communication system, not only requires the VCO its miniaturization and low cost, but also hope that VCO with frequency synthesizer and transceiver unit circuits are monolithically integrated, so as to reduce the volume and cost of the. In addition, monolithic integrated VCO design theory also is being deepened, more and more advanced design technology. Differential amplifier, amplitude control, two harmonic suppressor, IC coupling transformer, composite oscillator, high frequency structure design technology are being incorporated into the monolithic integrated VCO design. Using monolithic integrated VCO technology to high-quality VCO transceiver circuit integrated together with the new products continue to come out. For example, in WLAN and Bluetooth device, the new transceiver is made of high quality VCO and RF transceiver front-end IC integrated together, so that its size is greatly reduced. WLAN (2.4GHZ802.11b type and 5GHZ type 802.11a ) called VCO has very low phase noise.Because RF IC VCO technology unceasing development, satellite rece