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1、華 北 電 力 大 學 科 技 學 院畢 業(yè) 設 計(論 文)附 件外 文 文 獻 翻 譯學 號: 5 姓 名: 彭鈺釗 所在系別: 動力工程系 專業(yè)班級: 測控技術與儀器12K1 指導教師: 李冰 原文標題: Infrared Remote Control System Abstract 2016 年 4 月 19 日紅外遙控系統(tǒng)摘 要紅外數(shù)據通信技術是目前在世界范圍內被廣泛使用的一種無線連接技術,被眾多的硬件和軟件平臺所支持。紅外收發(fā)器產品具有成本低,小型化,傳輸速率快,點對點安全傳輸,不受電磁干擾等特點,可以實現(xiàn)信息在不同產品之間快速、方便、安全地交換與傳送,在短距離無線傳輸方面擁有十分
2、明顯的優(yōu)勢。紅外遙控收發(fā)系統(tǒng)的設計在具有很高的實用價值,目前紅外收發(fā)器產品在可攜式產品中的應用潛力很大。全世界約有1億5千萬臺設備采用紅外技術,在電子產品和工業(yè)設備、醫(yī)療設備等領域廣泛使用。絕大多數(shù)筆記本電腦和手機都配置紅外收發(fā)器接口。隨著紅外數(shù)據傳輸技術更加成熟、成本下降,紅外收發(fā)器在短距離通訊領域必將得到更廣泛的應用。本系統(tǒng)的設計目的是用紅外線作為傳輸媒質來傳輸用戶的操作信息并由接收電路解調出原始信號,主要用到編碼芯片和解碼芯片對信號進行調制與解調,其中編碼芯片用的是臺灣生產的PT2262,解碼芯片是PT2272。主要工作原理是:利用編碼鍵盤可以為PT2262提供的輸入信息,PT2262對
3、輸入的信息進行編碼并加載到38KHZ的載波上并調制紅外發(fā)射二極管并輻射到空間,然后再由接收系統(tǒng)接收到發(fā)射的信號并解調出原始信息,由PT2272對原信號進行解碼以驅動相應的電路完成用戶的操作要求。關鍵字:紅外線;編碼;解碼;LM386;紅外收發(fā)器。1 緒論11 課題研究的背景及意義紅外數(shù)據通信技術是目前在世界范圍內被廣泛使用的一種無線連接技術,被眾多的硬件和軟件平臺所支持。是一種通過數(shù)據電脈沖和紅外光脈沖之間的相互轉換實現(xiàn)無線的數(shù)據收發(fā)的技術。紅外收發(fā)器產品具有成本低,小型化,傳輸速率快,點對點安全傳輸,不受電磁干擾等特點,可以實現(xiàn)信息在不同產品之間快速、方便、安全地交換與傳送,在短距離無線傳輸
4、方面擁有十分明顯的優(yōu)勢。紅外收發(fā)器產品在可攜式產品中的應用作用很大。目前,全世界有1億5千萬臺設備采用紅外技術,在電子產品和工業(yè)設備、醫(yī)療設備等領域廣泛使用。比如有95的筆記本電腦就安裝了紅外收發(fā)器接口,現(xiàn)在絕大多數(shù)手機上也配置紅外收發(fā)器接口。而且隨著交換的數(shù)據量變大,紅外數(shù)據通訊將使手機的數(shù)據傳輸越來越方便。隨著紅外數(shù)據傳輸技術越來越成熟、完善、成本更低廉,紅外收發(fā)器在短距離通訊領域必將得到更廣泛的應用。本章首先闡述了紅外收發(fā)集成電路設計課題的背景和意義,然后簡要介紹了紅外數(shù)據通訊技術的特點和應用領域,以及紅外收發(fā)器產品的特點、國內外現(xiàn)狀和發(fā)展趨勢,最后根據紅外遙控收發(fā)系統(tǒng)的實際應用性確立了
5、課題的設計定位。12 紅外遙控收發(fā)系統(tǒng)簡介紅外遙控系統(tǒng)分為單通道遙控和多通道遙控。只有一個指令信號傳送通道的稱為單通道遙控系統(tǒng);具有兩個以上指令信號傳送通道的稱為多通道遙控系統(tǒng)。單通道遙控比較簡單 ,一般來說 ,發(fā)射器僅有一個指令鍵 ,接收器也只有一個執(zhí)行電路。雖然在接收電路中加入多穩(wěn)態(tài)記憶電路 ,可以根據按動發(fā)射器指令鍵的次數(shù) ,使接收電路中的多穩(wěn)態(tài)記憶電路的狀態(tài)多次改變 ,實現(xiàn)多項功能控制 ,但是這種狀態(tài)的改變是順序進行的。如果要實現(xiàn)一項任意控制 ,就要采用多通道遙控系統(tǒng)。多通道遙控可以實現(xiàn)對被控對象的任意多功能遙控。至于選用幾個通道及何種控制方式 ,要根據實際情況(如被控對象、操作要求及
6、成本核算等)來決定。一般的紅外遙控收發(fā)系統(tǒng)是由紅外遙控信號編碼發(fā)送器、紅外遙控信號接收器和解碼器(解碼芯片或單片機)及其外圍電路等三部分構成的。信號發(fā)送器用來產生遙控編碼脈沖,驅動紅外發(fā)射管輸出紅外遙控信號,接收器完成對遙控信號的放大、檢波、整形并解調出編碼脈沖。紅外遙控編碼脈沖是一組組連續(xù)的串行二進制碼,對于一般的紅外收發(fā)系統(tǒng),此串行碼作為微控制器的遙控輸入信號,由其內部CPU完成對遙控指令的解碼,對其他各種紅外遙控收發(fā)電子產品的設計者來說,上述的微控制器內部解碼出的遙控指令是不便于利用的。因此,人們利用紅外編/解碼芯片及單片機研制出多種通用紅外遙控收發(fā)系統(tǒng),在各種設備之間進行紅外信號的收發(fā)
7、。遙控收發(fā)系統(tǒng)一般由發(fā)射器和接收器兩部分組成。發(fā)射器一般由指令鍵、指令編碼電路、調制電路、驅動電路、發(fā)射電路等幾部分組成。當按下某鍵時 ,指令編碼電路,產生相應的指令編碼信號 ,編碼指令信號對載波進行調制 ,再由驅動電路進行功率放大之后由發(fā)射電路向外發(fā)射經過調制的指令編碼信號。接收器一般由接收電路、放大電路、解調電路、指令譯碼電路、驅動電路、執(zhí)行電路等幾部分組成。接收電路將發(fā)射器發(fā)射的已調制的編碼指令信號接收下來 ,并進行放大后送解調電路。解調電路將已調制的編碼信號解調下來 ,即還原為編碼信號。指令譯碼器將編碼指令信號進行譯碼 ,最后由驅動電路來驅動執(zhí)行電路實現(xiàn)各種指令的操作控制。13 紅外遙
8、控收發(fā)器產品概況1.3.1紅外遙控收發(fā)器產品的結構和類型目前紅外收發(fā)器按照工作模式和傳輸速率可分為四類:串行模式,最高速率為115.2Kbps;中速模式:最高速率為0.567Mbps和1.152Mbps;高速模式:最高速率為16Mbps。另外按芯片功耗大小又可以分為低功耗型和標準型兩類,低功耗型通常使用3V電源,傳輸距離較近,約0-30cm,標準型通常使用5V電源,傳輸距離較遠最少1m以上。1.3.2紅外遙控收發(fā)器的國內外現(xiàn)狀在紅外通信技術發(fā)展的早期,存在好幾個紅外通信標準,不同標準之間紅外設備不能進行紅外通信。為了使各種紅外設備能夠互聯(lián)互通,1993年由20多個大廠商發(fā)起成立了紅外數(shù)據協(xié)會(
9、IRDA)統(tǒng)一了紅外通信的標準,這就是目前被廣泛使用的紅外數(shù)據通信協(xié)議及規(guī)范,也稱為IRDA標準。自1993年IRDA成立至今,紅外數(shù)據協(xié)會的會員已經發(fā)展到150多個,IRDA標準已經獲得了業(yè)界廣泛認同和支持。已經開發(fā)出來的具備紅外通訊能力的設備已經有一百多種之多,紅外模塊的年裝機量已經達到一億五千萬套。盡管現(xiàn)在有了同樣是近距離無線通訊的藍牙技術,但以紅外通訊技術低廉的成本和廣泛的兼容性的優(yōu)勢,紅外數(shù)據通訊仍舊會在將來很長一段時間內在短距離的無線數(shù)據通訊領域扮演重要角色。由IRDA協(xié)會的資料表明,國外公司的紅外收發(fā)器產品起步較早,已經形成了紅外收發(fā)器的配套生產產業(yè)鏈。由以下部分組成:Sharp
10、等公司主要提供紅外發(fā)光二極管和光敏二極管;Agilent等公司主要設計制作紅外收發(fā)芯片;Infineon等公司主要從事紅外收發(fā)器封裝;IBM、Microsoft等公司則推出紅外數(shù)據收發(fā)器驅動程序和紅外通信軟件。其中如Agilent等公司還具有生產紅外收發(fā)器系列產品的能力,而HP、IBM等大公司則專門為自己公司產品配備紅外收發(fā)器。在中國臺灣地區(qū)也形成了一批紅外收發(fā)產品的生產廠家和公司,但在大陸地區(qū)只有一些器件銷售公司在做這些國際公司和臺灣公司的代理,缺乏具有自主產權的該類產品。1.3.3紅外收發(fā)器產品的發(fā)展趨勢在各種紅外收發(fā)器產品中,雖然傳輸速率、傳輸距離等特性不同,但紅外收發(fā)器產品一直朝著提高
11、傳輸速率,增加傳輸距離,降低功耗,擴大發(fā)射接收角度等方面發(fā)展。特別是隨著技術發(fā)展和成熟,傳輸方式正朝著點對多點方向發(fā)展。因此紅外遙控收發(fā)器產品還有更加寬廣的發(fā)展前景。2 紅外通信的基礎知識21紅外線基礎知識2.1.1紅外線概述紅外線實質上是一種電磁波。從分析自然界中各種電磁波組成的波可知,波譜是由 :射線,射線、紫外線、可見光、紅外線、微波和無線波組成的。從形式上看,它們之間似乎沒有關系,但如果按照他們的波長依次排列,就會發(fā)現(xiàn)和我們形影不離的可見光只占了整個波譜中0.38m-0.76m長的這么一點兒范圍,而和可見光相鄰的紅外線 (包括遠紅外線、中紅外線和近紅外線外)卻占了波譜中0.76m-10
12、00m的一大段。其中微米波長范圍內又包括了紫外光 、可見光、近紅外、中紅外 、遠紅外、微波。從上述分析可知,紅外線是一種十分豐富的波譜資源,目前它己在生產、生活、軍事、醫(yī)療等多方面得到了廣泛的應用,例如紅外線加熱、紅外線醫(yī)療期間、紅外線通信、紅外線攝像、紅外線遙控等。紅外線遙控只是紅外線眾多應用中的一部分,目前在家用電器中廣泛應用的彩電遙控器、錄像機遙控器、 VCD遙控器、高保真音響遙控器等,都采用了紅外線遙控,它使這些家用電器的控制變得十分簡單方便。2.1.2紅外線的特性紅外線是介于可見光和微波之間的一種電磁波,因此它具有相臨波的某些特性。在近紅外區(qū),它和可見光相鄰,因此具有可見光的某些特性
13、,如直線傳播、反射、折射、散射、衍射、可被某些物體吸收以及可以通過透鏡將其聚焦等。在遠紅外區(qū),由于它鄰近微波區(qū),因此它具有微波的某些特性,如較強的穿透能力和能貫穿某些不透明物質等。在自不論任何物體,然界中,也不論其本身是否發(fā)光 (指可見光) 只要其溫度高于絕對零度 (-273),都會一刻不停地向周圍輻射紅外線。只不過是溫度較高的物體輻射的紅外線較強,溫度低的物體輻射的紅外線較弱。因此紅外線的最大特點是普遍存在于自然界中,又叫做熱輻射線簡稱熱輻射。紅外線攝像、紅外線夜市、熱釋電紅外探測以及某些導彈的瞄準等就是利用紅外線的這一特性工作的。紅外線和可見光相比的另一個特點是,色彩豐富多樣。由于可見光的
14、最長波長是最短波長的1倍(780nm-380nm),所以也叫作一個倍頻程。而紅外線的最長波長是最短波長的1倍,而紅外線的最長波長是最短波長的10倍,即有10個倍頻程。因此如果可見光能表現(xiàn)為7種顏色,則紅外線便可能表現(xiàn)70種顏色,顯示了豐富的色彩。紅外線透過煙霧的性能好,這是它的又一個特點。由于紅外線為不可見光 ,因此對環(huán)境影響很小。再由紅外光波的波長遠小于無線電波的波長 ,所以紅外線遙控不會影響鄰近的無線電設備。另外波長小于 1.5m 的近紅外光 ,在透明大氣中的傳輸特性要比可見光好得多 ,而且由于它靠近可見光的紅光邊緣 ,其直線傳播、反射、折射和被物質吸收等物理特性與可見光非常相似。因此 ,
15、它可以使用與可見光類似的聚焦透鏡等光學裝置。由于紅外線遙控不具有像無線電遙控那樣穿過障礙物去控制被控制對象的能力 ,所以 ,在設計家用電器的紅外線遙控器時 ,不必要像無線電遙控那樣 ,每一套(發(fā)射器和接收器)要有不同的遙控頻率或編碼(否則 ,就會隔墻控制或干擾鄰居的家用電器) ,所有同類產品的紅外線遙控器 ,可以有相同的遙控頻率或編碼 ,而不會出現(xiàn)遙控信號“串門”的情況。這對于普及紅外線遙控提供了極大的方便。紅外線為不可見光線 ,具有很強的隱蔽性和保密性 ,因此 ,在防盜、警戒等安全保衛(wèi)裝置中也得到了廣泛地應用。紅外線遙控具有結構簡單、制作方便、成本低廉、抗干擾能力強、工作可靠性高等一系列優(yōu)點
16、 ,是近距離遙控、特別是室內遙控的優(yōu)選遙控方式。Infrared Remote Control SystemAbstract Red outside data correspondence the technique be currently within the scope of world drive extensive usage of a kind of wireless conjunction technique,drive numerous hardware and software platform support. Red outside the transceiver pro
17、duct have cost low, small scaled turn, the baud rate be quick, point to point SSL, not by the electromagnetic interference etc.characteristics, can realization information at dissimilarity of the product fast, convenience, safely exchange and transmission, at short distance wireless deliver aspect t
18、o own very obvious of advantage.Along with red outside the data deliver a technique more and more mature, the cost descend, red outside the transceiver necessarily will get at the short distance communication realm more extensive of application.The purpose that design this system is transmit custome
19、rs operation information with infrared rays for transmit media, then demodulate original signal with receive circuit. It use coding chip to modulate signal and use decoding chip to demodulate signal. The coding chip is PT2262 and decoding chip is PT2272. Both chips are made in Taiwan. Main work prin
20、ciple is that we provide to input the information for the PT2262 with coding keyboard. The input information was coded by PT2262 and loading to high frequent load wave whose frequent is 38 kHz, then modulate infrared transmit dioxide and radiate space outside when it attain enough power. The receive
21、 circuit receive the signal and demodulate original information. The original signal was decoded by PT2272, so as to drive some circuit to accomplish customers operation demand.Keywords:Infrared;Code;Decoding;LM386;Redout-side transceiver1 Introduction1.1 research the background and significance Inf
22、rared Data Communication Technology is the world wide use of a wireless connection technology, by the many hardware and software platforms supported. Is a data through electrical pulses and infrared optical pulse switch between the wireless data transceiver technology.Infrared transceiver products w
23、ith low cost, small, fast transmission rate, the point-to-point transmission security, not subject to electromagnetic interference and other characteristics that can be achieved between the different products, rapid, convenient and safe exchange and transmission, In short distance wireless transmiss
24、ion have a very distinct advantage.Infrared transceiver products in the portable product of a great role. At present, the worlds 150 million piece of equipment used infrared technology in electronic products and industrial equipment. medical equipment and other fields widely used. For example, 95% o
25、f the notebook computers on the installation of infrared transceiver interface the majority of the cell phone is also the allocation of infrared transceiver interface. With the exchange of quantitative data, infrared data communications will enable cell phone data transmission more convenient. With
26、infrared data transmission technology matures, perfect, low costs, Infrared Transceiver in short distance communications will be more widely applied. This chapter first describes the infrared transceiver IC design issues to the background and significance. then briefed the infrared data communicatio
27、ns technology features and applications, and infrared transceiver product characteristics, domestic and international situation and development trend of the last under infrared remote transceiver system in practical application to establish a task of design orientation.1.2 Infrared Remote Control Tr
28、ansceiver SystemInfrared remote control system is divided into single-channel and multi-channel remote control. Only a command signal transmission channel, called single-channel remote control system; with more than two instructions signal transmission channel known as a multi-channel remote control
29、 system. Relatively simple single-channel remote control, in general, only a launcher directive Key receivers and only one circuit implementation. While in the receiving circuit to add more stable memory circuits that can be activated commands to launch a number of key, so that the receiver circuit
30、multistate memory circuit repeatedly to change the state, to realize many of the functional control, But such a state of change is the order. If we are to achieve an arbitrary control, resort to the use of multi-channel remote control system. Multi-channel remote control can be realized by the objec
31、t of arbitrary multi-function remote control. As for the choice of several routes and what control methods, according to the actual situation (such as object, operational requirements and cost accounting, etc.) to decide. General infrared remote transceiver system by infrared remote control transmit
32、ter signal coding, infrared remote control signal receivers and decoders (or decoder chip MCU) and the external circuit consisting of three parts. Signal transmitter remote control code used to generate pulses of infrared emission-driven output infrared remote control signal, receiver completion of
33、the remote control signal amplification and detection, plastic and demodulation encoding pulse. Infrared remote control coded pulse is going to obtain a continuous serial binary code, and for most of the infrared transceiver system, This serial code as micro-controller of the remote control input si
34、gnals from the internal CPU completion of the remote control instruction decoder, on the other infrared remote control transceivers, the designers of electronic products, The internal micro-controller of the remote control decoder directive is not accessible. Therefore, people are using infrared enc
35、oder / decoder chip and micro-controller developed various generic infrared remote transceiver system, In various equipment infrared signals between the transceiver.Remote transceiver system generally transmitters and receivers is composed of two parts. Launchers from the general direction keys, cod
36、ed instructions circuit modulation circuit, driving circuit, firing circuit of several parts. When pressed a key, the directive coding circuit, in the corresponding instructions encoded signal, the encoder signal to the carrier modulation, Driven by the power amplifier circuit after circuit fired fr
37、om the field after firing instructions coded modulation signals. General receiver by the receiving circuit, the amplifier circuit, demodulation circuits, instruction decoder circuit, driving circuit, circuit implementation of several parts. Receiving Circuit will launch vehicles have been coded modu
38、lation signal receiving instructions from, and to enlarge evacuation demodulation circuit. Demodulation circuit will have the coding modulation signal demodulation, namely, reduction of signal coding. The instruction decoder to the encoder signal decoding, Driven by the final circuit to drive the im
39、plementation of various instructions circuit to control the operation.1.3 infrared remote control transceiver product profiles1.3.1 infrared remote control transceiver product structure and type Currently infrared transceiver in accordance with the mode of transmission rate and can be divided into f
40、our categories : Serial mode, the highest rate of 115.2 Kbps; medium-speed model : the highest rate of 0.567 Mbps and 1.152Mbps; High-speed mode : The maximum rate of 16 Mbps.Also according to the size chip power consumption can be divided into low-power consumption and standard two categories, low-
41、power type normally used 3 V power supply, transmission distance closer to about 0 - 30cm, which is commonly used standard 5V power supply, transmission distance away at least 1m above.1.3.2 infrared remote control transmitters of the status quo at home and abroadInfrared communication technology in
42、 the development stage and there are several infrared communication standards, between different standards for infrared equipment can not infrared communication. To have all the infrared equipment to interoperability in 1993 by more than 20 large manufacturers initiated the establishment of an Infra
43、red Data Association (IRDA) unified the infrared communication standards , which is currently widely used in infrared data communication protocols and standards, also known as the IRDA standard.Since 1993 IRDA since the establishment of the Infrared Data Association members have developed to more th
44、an 150. IRDA standards of the industry has been widely recognized and supported. Has been developed with the infrared communications equipment have been as many as 100 species. IR module, installed capacity has reached 150 million sets. Although there is also a short distance wireless Bluetooth tech
45、nology, But in infrared communication technology low cost and broad compatibility advantages, Infrared data communication in the future will still be a very long time inherent short-range wireless data communications fields play an important role.1.3.3 Infrared Transceiver product development trendI
46、n various infrared transceiver products, although the transmission rate, transmission distance and other characteristics, But infrared transceiver products has been towards improving the transmission rate, increase the transmission distance and lower power consumption, expanding launch reception ang
47、le of development. In particular, as the technology development and maturity, the means of transmission is moving in the direction of point-to-multipoint. Therefore infrared remote control transceiver products have broader prospects for development.2 Infrared communication of knowledge2.1 infrared r
48、ay foundation knowledge2.1.1 infrared outlined Infrared is actually a kind of electromagnetic wave. From the analysis of various natural component of the electromagnetic wave reflected spectrum is :-ray, x-ray, ultraviolet, visible, infrared, microwave and radio wave. From the viewpoint of form, and
49、 they did not seem to, but if the wavelength in descending order, and we will find him all the only visible light spectrum of the entire 0.38 m - 0.76m so long little area, and adjacent to the visible light and infrared (including the far infrared, mid-infrared and near infrared foreign) accounts fo
50、r the spectrum of 0.76 m - 1000m of a major. Which micron wavelength range also includes UV, visible, near infrared, mid-infrared and far-infrared, microwave. From the above analysis shows that infrared is a very rich spectrum resources, it currently has in production, life, military, medical, and o
51、ther aspects have been widely used, such as infrared heating, medical infrared, infrared communication, infrared camera, infrared remote control, and so on. Infrared remote control is the many applications of infrared part of the current household appliances widely used in TV remote control, VCR rem
52、ote control, VCD remote control, high-fidelity audio remote control, are used infra-red remote control, It allows the control of these appliances have become very easy.2.1.2 infrared propertiesInfrared lies between visible light and microwave a wave, it is with certain clinical characteristics of th
53、e wave. In the near-infrared, visible light and its adjacent, it is visible in certain characteristics, such as straight-line transmission, reflection, refraction, scattering, diffraction, can be certain objects and can be absorbed through the lens of their focusing. In the far-infrared region, owin
54、g to its neighboring microwave, it has some characteristics of microwave, If a strong penetrating power and can run through some opaque substances. Since in any object, natural profession, regardless of whether its own luminescence (referring to visible light), as long as the temperature is above ab
55、solute zero (-273 C), moment will be kept around to infrared radiation. Only higher temperature of objects strong infrared radiation, low-temperature objects infrared radiation weaker. Therefore infrared feature is the greatest common in nature, it is called thermal radiation called thermal radiatio
56、n. Infrared cameras, infrared night market pyroelectric infrared detectors and some other missiles aiming at is the use of this characteristic of infrared work.Infrared and visible light compared to another characteristic of a variety of colors. As the longest wavelength of visible light is a wavelength of the shortest times (780 nm-380 nm), So is called an octave. And infrared wavelength is the longest shortest wavelength of a times, and the longest w
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