1、 Infrared Remote Control System Abstract 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 product have cost low, sm
2、all scaled turn, the baud rate be quick, point to point SSL, be free from electromagnetism thousand Raos etc.characteristics, can realization information at dissimilarity of the product fast, convenience, safely exchange and transmission, at short distance wireless deliver aspect to own very obvious
3、 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 customers operation info
4、rmation 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 principle is that we
5、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 attian enough power. The receive circuit receive
6、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:Infrare dray； Code； Decoding； LM386； Redoutside transceiver 1 Introduction 1.1 research the background and significance Infrared D
7、ata 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 with lo
8、w 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 transmission ha
9、ve 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% of the
10、 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 infra
11、red 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 communications te
12、chnology 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 ControlTransce
13、iver System Infrared 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 sys
14、tem. 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 mult
15、istable 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 object o
16、f 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 transmitter
17、 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 the
18、 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 signa
19、ls 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 encode
20、r / decoder chip and microcontroller 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, coded
21、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 from
22、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 modulat
23、ion 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 imple
24、mentation of various instructions circuit to control the operation. 1.3 infrared remote control transceiver product profiles 1.3.1 infrared remote control transceiver product structure and type Currently infrared transceiver in accordance with the mode of transmission rate and can be divided into fo
25、ur 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-
26、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 abroad Infrared communication technology
27、in 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 Inf
28、rared 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
29、 than 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 t
30、echnology, 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 tr
31、end In 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 receptio
32、n angle 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 knowledge 2.1 inf
33、rared ray foundation knowledge 2.1.1 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 f
34、orm, and 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) acc
35、ounts for 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, medica
36、l, and other 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,
37、 VCR remote 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 properties Infrared lies between visible light and microwave a wave, it is with certain clinical characteris
38、tics of the 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 re
39、gion, owing 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 i
40、s above absolute 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 therma
41、l radiation. 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
42、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 wavelength infrared is the shortest wavelength of 10 times, that is, 10 octave. Therefore, if visible light can be expressed as seven
43、colors, infrared may performance 70 colors, showing the rich colors. Infrared smoke through the good performance, which is also one of its features. Because not visible to the infrared, it has little effect on the environment. By the wave infrared rays than the long wavelength radio waves, infrared
44、remote control will not affect the nearby radio equipment. Another wavelength of less than 1.5m near infrared light, transparent atmosphere in the visible light transmission characteristics much better than, because it close to the visible edge of the red light, linear transmission, reflection, refr
45、action and absorption material and the physical characteristics very similar to visible light. Therefore, it can be used with similar visible focusing lens and other optical devices. Because infrared remote control is not as remote as the radio through the barrier to control the objects ability to c
46、ontrol, so in the design of household appliances infra-red remote control, wireless remote control as unnecessary, each set (transmitters and receivers) have different frequency or remote coding (Otherwise, wall will control or interference with neighbors household appliances), all similar products
47、in the infrared remote control, The same can control the frequency or coding, and no remote control signal “drop.“ This universal infrared remote control provides a great convenience. Infrared to visible light, is very subtle and confidentiality, therefore, the security, Alert and other security dev
48、ices have been widely used. Infrared remote control is simple in structure and easy, low-cost, anti-interference capability, high reliability are a number of advantages, is a close-up remote control, especially in indoor remote control optimized manner. 2.1.3 infrared diode characteristics Infrared
49、is not visible, people here are not aware of. Electronic technology is used infrared light emitting diode (also known as the IR emission diode) to generate infrared. Infrared remote control transceiver is using near-infrared transmission control instructions 0.76m wavelength of 1. 5m. Near-infrared remote control as a light source, because there infrared light emitting diodes and infrared receiving device (photodiode. Transistor and PV) and the luminescence peak wavelength of light by the general 0.8m 0. 94m. in the near-infrared band, both of the spectrum is the c
