08电子8_基于单片机的防盗报警器的设计(英文翻译)_2012.6.1.doc

大连理工大学城市学院本科生毕业设计（翻译）学 院： 电子与自动化学院 专 业： 电子信息工程 学 生： 指导教师： 王颖 完成日期： 2012年6月1日 Multifunctional Intelligent Wireless Alarm SystemAbstract: Making use of rich inner resource of FPGA(Field Programmable Gate Arrays), a wireless alarm sending system is designed. It includes encoder, FSK(Frequency Shift Keying) modulation and every channels control circuits, which can decrease volume and increase reliability of the alarm system.The demodulation of receive system is realized by an application specific integrated circuits MC3372. With the help of a single-chip microcomputer 89C51, the address decoder is also designed in the receiver. Adding to other anti-interference,the alarming system has effectively decreased the error-alarm rate. The system can install up to 128 channel sending devices. It can send an alarm to the host when there are some cases in stand-off areas, and the system will display on rotation multiple cases area codes . The transmission distance is greater than 4Km in open zones. User can install more than one type sensors simultaneously, for example, smog sensor, combustible gas sensor or burglar sensor. Experiments show that the wireless alarm system has the strengths of high reliability, high anti-disturbance ability and low error-alarm rate. It can entirely meet the needs of alarm fireproofing and guard against theft, etc.Keywords: communication; Alarm systems; Frequency Shift Keying; Micro-controllers; Field Programmable Gate Arrays I. INTRODUCTION Compared with a wired alert system, a wireless alarm system has characteristics of covertness and ease of installation. It is especially effective when transmitting between long distances in a complex landform situation. Made up of FPGA (Field Programmable Gate-Array), the encoding module in the sending system creates the address signal, FSK (frequency shift keying) modulates the signal and each channels controller signals. Using FPGA to replace MSI/SSI (Middle Scale Integrated or Small scale Integrated) digital circuit devices, not only increase the reliability and the resistance to interference of the alarm system, but it also decreases its volume and makes the system easier to install. Since used 7 bits binary number to express the address, up to 128 channels sender can be installed. The decoder consists of ASIC (Application Specific Integrated Circuit) and SCM in the wireless alarm receiver system, which can effectively decrease the error-alarm rate.II. THE SENDING SYSTEM PRINCIPLE Each stand-off is equipped with a wireless sending system,and corresponds with a 7 bits address identifier in binary. Once a case is detected by a sensor in any stand-off, a control signal of this area is sent to its encoding circuit via interface circuit, which converts the areas 7bit address identifier into FSK signal. Then FSK signal is transmitted into a frequency modulation circuit for frequency modulating. After power amplification, the frequency modulation electromagnetic wave is emitted via antenna. One characteristic of the sending system is discontinuous sending. In other words, the sending system does not send signals when there is no case, and do keep sending when there is an alarm situation, so as to provide chances to send signals for other stand-off areas. A. The Encoding and Controlling Circuit Configuration The digital circuit part of the encoding circuit is made by a FPGA chip which includes 8 modules.Formed by D triggers, module dff1 is the interface between detector and encoder. Module oscillator combines with some external resistors and capacitors to form a controllable low frequency multivibrator. Its control signal is the output of dff1-Q1. It does not vibrate when Q1is equal to 0, and if Q1is equal to 1, it vibrates to generate low frequency square waves. If some cases appear in the area, the oscillator controls the module SENDER to send electromagnetic wave discontinuously. The module circular_shift_r is a parallel input serial output circular shift register. The bit A0A7 are the parallel address code input terminals, which are joined to high or low voltage level according to the encoder requirement. Q8 is the serial output terminal of the address code. Module dff2 is a control circuit that is made of some JK triggers. Its setup signal is Q1, which also acts as a trigger signal after delay. Q2 acts as the parallel-in-serial-out control terminal of thecircular_shift_r module. When Q2 is at high voltage level,circular_shift_r performs parallel input. When Q2 is at low voltage level, circular_shift_r executes serial output. The module delay1 is a delay circuit composed of D triggers.The module division is a frequency division that creates three different routes frequency output signals, two of which branches and act as FSK modulating signals: f1 and f2. The other branch acts as a triggering pulse for modules dff1 and delay1, and also acts as the clock pulse of circular_shift_rfor performing serial-out. The module MUX is a 2 to 1multiplexer. Its control signal is the output Q8 ofcircular_shift_r. When Q80, MUX produces the signal f2, and when Q81, it exports f1. The module delay2combines with some external resistors and capacitors to form a delay circuit. Its function is to give workers some time to leave after installing the system. The sending circuit does no work within the delay time, no matter whether K1(detector) is on or off. This is the external connection drawing of the FPGA chip.B. The Working Principle As shown following, the working principle of the alarm system is as follows: when the power of the sending system turns on, the input of the dff1 is at low level. Then its output terminal Q1 is at logic value 0, NQ1 is at logic 1, and a external light-emitting diode (LED) is lit to indicate the power is on. The signal Q1 is sent to the setting terminal of dff2 to set terminal Q2 at high level. The high level Q2 will set circular_shift_r into the parallel input address code mode. At this time, the outer transistor N2 is at saturation state and N3 at cut-off state. This makes the sending circuit at a passive state, therefore, the circuit will not work. Hence, the circuit does not emit carrier wave if there is no case, and it is at low consumable power state.Once some cases appear, the switch K1 is on. The terminal D of the dff1 turns to high level immediately, and the output Q1of dff1 is set to high level at the rising edge of the clock pulse. It makes the setting terminal s of dff2 at high level too. The dff2 now is at normal working state. After delaying by module delay1, the former edge of the Q1 pulse will trigger dff2 to output low voltage, which will make the transistor N2 off, N3 on, and the delays normally open contact will be closed. The electric power supply to the sending circuit is on, and the circuit begins to work normally. Simultaneously, if Q2 is at logic 0, circular_shift_r will be change to serial shift state and export address signals. When the address code is 0, the output of MUX will be f2. And when the address code is 1, the output will be f1. Terminals f2 and f1 act as the modulation signal for modulating the carrier wave. In this way, the address code is sent out at the first cycle of the low frequency oscillator. At the second cycle it stops sending in order to give other stand-off a period of time to send. After the third cycle, repeat the procedure above. From the discussion above, we have the conclusion that the encoding and control circuit have the function to display when the power is on, time delay for human to leave the spot, low power cost mode for waiting case, discontinuity sending and FSK modulating etc. It is more flexible and has more functions than many encoder ASIC. III. THE CONFIGURATION AND PRINCIPLE OF THE RECEIVING SYSTEM Set in guardhouse, a set of wireless receiver takes charge of monitoring all stand-off areas. The principle of the wireless receiver is show following. Passing by the low pass filter, the received modulation signal is sent into the high frequency common-emitter and common-base configuration cascade amplifier for amplifying. Then the signal is sent to the intermediate frequency modulation amplifier via the dual tuning circuit, i.e. sent into the input terminal (16th pin) of an ASIC chip (MC3372) to do mixing. The oscillate frequency of the local oscillator circuit is 455KHz higher than the received signal. Delivering to the first pin of the chip MC3372, the signal will mix with the external signal to get 455KHz intermediate frequency signal. After filtering, the intermediate frequency signal is first delivered to the 8th MC3372 pin to do frequency detection, and second amplified by an inner low frequency amplifier of the chip MC3372, then the 9th pin exports the baseband signal. Amplified by a low frequency single transistor, the baseband signal is rectified by two steps Schmitt gates (CD4584) to turn into a FSK signal, which will be sent into pin 3.0 of MCS to be decoded. MCS in this system is chip 89C51, which joins an outer 12MHZ crystal oscillator. Its timer T1 act as a baud rate generator in mode 2, and SMOD=1,300 baud/sec. serial port is selected in mode 1, which means an asynchronous communication mode, 10 bit per frame in which the lower 7 bits of the 8 data bit is the address code, and the 8th acts as the parity check bit. The system uses even check. When receiving an address code, the MCS firstly performs parity check. If it is correct ,then ,the MCS compare their value and takes out 7 bits address code and stores it into data buffer in memory. These procedures repeat 3 times in order to identify the 3 address codes. If the 3 address codes are the same, the MCS will confirm that the receiving address signal is an effective alarm signal, that is to say, the address code is not a noise signal. It then triggers the alarm circuit to send the alarm sound. At the same time, the code number will display on the LED indicating which stand-off triggered the alarm. The LED uses a dynamic scan display method. If there are more than one stand-off areas have cases simultaneously, the MCS will display their code number in turn at 3 seconds intervals. The alarm audio process circuit uses a NE556 dual time base circuit chip to form a dual audio frequency multivibrator, which will give off a ringing alarm sound. System could configure sensors use for alarm of fire,combustible gas and theft.IV. ANTI-INTERFERENCE MEASURE It is important to heighten the anti-interference ability for wireless communications. anti-disturbance measures takes form in the hardware. For example, one should reasonably arrange the PCB (printed circuit board)，increase power decoupling, and place the high and low frequency filter reasonably. Since the receiver system includes high frequency circuits, separate the analogue circuit and digital circuit chip, and make each have its own ground. To guard against external and internal interference or high frequency radiation, put the high frequency amplifier and middle frequency amplifier channels in a metallic shield box and the MCS system into another metallic shield casket. Adopt FSK modulation, double tuning select frequency and ASIC demodulation. All of these measures can effectively decrease interference to the system. For software, use the modular structure to design the software system. Continuously distinguishing address code several times and by parity check can dramatically reduce the error-alarming rate of the system.V. THE ENDING The design of software and hardware in this alarm system is reasonable. Its reliability is observably increased, and the error alarm rate is decreased. Experiments show that the error alarm rate is nearly zero when disconnecting the detector. The transmission distance is greater than 4Km in open zones When connecting microwave dual discriminating theft-proof detector（DT-400 Family）, the error alarm rate is less than 4 times every 1000 hours. Since working in the discontinuously sending method at 300baud/s, the alarm system can work reliably as long as the time gap between two sending systems is less than 0.2sec. In fact, it can meet the need in actual applications. Intelligent Residential Security Alarm and RemoteControl System Based On Single Chip Computer Abstract： For to steals, robs and so on accidents to carry on the effective monitor and the warning, unified using the MCU AT89C51 controlling technology and the infrared detection technology, one kind of wireless burglar alarm has been designed, it including hardware and software two parts; The hardware part is composed by the infrared sensor, send and receive module ,MCU, acousto-optic warning and so on; The software part is composed of the main program and music subroutine. With C or the assembly language compilation source program, carries on the translation and the debugging in the Keilc51 platform, after downloads to the MCU AT89C51 chip, and this MCU and other primary devices welding on the PCB board according to design a circuit. On electricity, closed-cycle control switch, when some people intrude in the infrared launch area, has the acousto-optic warning, indicated that has achieved the design requirements.This paper presents intelligent residential burglar alarm, emergency alarm, fire alarm, toxic gas leakage remote automatic sound alarm and remote control system, which is based on 89C51 single chip computer. The system can be automatic alarm, automatic calling the police hotline number. It can be used voice alarm and show alarm occurred address. It can set up and modify user password. It can be recordable and voice suggestion. It can be used telephone remote control electrical power. The alarm system has design innovation, multiply function, low cost, high reliability and so on. Along with time unceasing progress, the people located the environment security to oneself to propose a higher request, it was living at the security aspect particularly, it must pay attention these unexpected visitors frequently. Now many plots have installed the intelligence alarm system, thus enhanced the plot safety rate greatly, because infrared is a black light, uses the wireless launch and the receive, does not need the independent wiring,it has the very strong confidentiality and the secrecy, thus in security, security installments and so on security the use should have the very big superiority.Keywords- Infrared sensor; Launch; Receive; MCU(Micro Controller Unit); WarningI. INTRODUCTION With the computer technology and control technology and communicational technologys development, peoples living standard has improved increasingly. Peoples living conditions have changed, Such as the living environments security and how comfortable they feel. So the intelligent residential buildings automatic emerge as the times require. Intelligent residential must have safety precautions, anti-theft alarm, fire alarm, toxic gas leakage automatic alarm and emergency call. It is able to implement remote control for the key equipment power. In recent years, with the progress of technology and economy, the electronic anti-theft alarm system has rapid development and a very wide application. Now it does not only apply in many important government departments, but also apply in the family. In-depth study on various alarm device, we have designed intelligent residential security alarm and remote control system on the basis of single chip computer. The system is based on 89C51 single chip computer, has intelligent residential burglar alarm, emergency call alarm, fire alarm, toxic gas leakage automatic alarm and remote control. It is able to call the police hotline number. It is able to use voice alarm and show alarm occurred address. Users can set up and modify password for it. It can be recordable and voice suggestion and make use of the telephone to remote control. Calling when is not at home, it can use password to enter remote deployment and remote control the power of electronic appliance. The system makes use of communication equipment to realize multi-channel detection, scene alarm, emergency alarm, fire alarm and toxic gas leakage automatic alarm. It realizes remote voice alarm function through the automatic dial-up telephone. It directly parallels on the telephone lines, then may be used. Before used, user will be required to install the detection device in place where being watched by people. It must be set up alarm telephone number, recorded voice alarm. The alarm system has design innovation, multiply function, low cost, high reliability and so on.II. SYSTEM COMPONENT Intelligent residential security alarm and remote control system constitutes as shown following. The system is through telephone interface circuit and telephone network to link up. 89C51 single chip computer dominates by MT8880 Dual Tone Multi-frequency (DTMF) codec with the telephone network to exchange information. When the detection of dangerous situations, the dangerous situation coded signal transfer from the corresponding detection module through the antenna to master chip. The master chip brings the corresponding alarm information according to received signal. This part is to complete by the voice interface circuit, which uses ISD1420. After users call the number of system, users can control appliances according to sound by the voice interface circuit. The system components are made up of detecting circuit, wireless transmitter-receiver circuit, telephone interface, voice circuit, DTMF codec circuit, telephone signal detection circuit and the main control circuit. Each module is described as follows:A.