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Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,GE Security,Training,Advent,Wireless Technology,RF Basics/,射频技术基础,Wireless Technology,Wireless In Everyday Life,日常生活中的无线技术,Radios/,无线电,TVs/,电视,Cordless Telephones/,无绳电话,Garage Door Openers/,车库门开闭器,Cellular phones/,蜂窝电话,Wireless Technology,无线技术,RF-the specific cycles per second of electromagnetic waves traveling through the air without wires.,RF is measured in Hertz/RF,的测量单位是赫兹,Frequency Bands are allocated and controlled by the FCC/,美国的无线频率管理机构是,FCC,Common uses of RF/,常见的,RF,应用,Cell Phones-900 MHz band/,移动电话,Pagers-900 MHz band/,寻呼机,Garage Door Openers-300 MHz band/,车库门开闭器,Security Systems-300-900 MHz bands/,安防系统,Frequency Band Designations/,频段划分,Frequency Band Designation Frequency Range,Min Max,ELF,极低频,-Extremely Low Frequency30 Hz 300Hz,VF,声频,-Voice Frequencies300 Hz 3000 Hz,VLF,超低频,Very Low Frequency 3 KHz 30 KHz,LF,低频,-Low Frequency30 KHz 300 KHz,MF,中频,Medium Frequency 300 KHz 3000 KHz,HF,高频,-High Frequency3 MHz 30 MHz,VHF,甚高频,-Very High Frequency 30 MHz 300 MHz,UHF,超高频,-Ultra High Frequency 300 MHz 3000 MHz,SHF,特高频,-Super High Frequency 3 GHz 30 GHz,EHF,极高频,Extremely High Frequency30 GHz 300 GHz,Wireless Security Systems,无线安防系统,40 MHz-24 Wavelength,great open air range,poor structural penetration,good battery life./,24,英尺波长，极佳的开阔地传播距离，穿透性较差，功耗小。,319.5 MHz-36”Wavelength,good open air range,good structural penetration,good battery life./,36,英寸波长，空旷地带传播、穿透性和功耗均佳。,900 MHz-8”Wavelength,great structural penetration,interference is also possible at 900 MHz,poor battery life./,8,英寸波长，穿透性极佳，干扰较多，功耗大。,Wireless Transmission,无线传输,To transmit information using RF a carrier and some type of modulation is required/,利用,RF,传输信息，需要使用载波和某些调制技术,Carrier-the specific frequency to carry the information/,载波,-,使用特定的频率来携带信息,Modulation-the means of encoding information on the carrier frequency/,调制,-,将编码信息处理并添加到载波上,Frequency Bandwidth,频宽,Bandwidth-a measurable area that information is transferred within/,带宽,-,一个传输信息的可测量的区域,Receivers bandwidth must be as larger or larger than the transmitters bandwidth/,接收机带宽必须同发射机的带宽相同或大于发射机,The closest the match the more reliable the RF path/,二者越接近、越匹配则,RF,传输路径越可靠,Narrow Band Advantages,窄波段的优势,Smaller System devices/,更小的设备体积,Longer Battery Life/,更长的电池寿命,More Reliable/,更可靠,Low Current Consumption/,较低的电流功耗,Quieter Frequency/,频率更安静,Penetrates Buildings Better/,建筑物穿透性较佳,SAW,vs,Crystal,两种发生器对比,Technologies used in receiving and transmitting information/,指的是接收和发送信息采用的技术,SAW refers to Surface Acoustic Wave and provides good frequency accuracy at a moderate,cost/SAW,意指声表面波技术，能提供良好的频率精确性和适中的成本,Crystal,by using a quartz crystal provides the highest frequency accuracy at a slightly higher cost/,石英晶体器件可提供更高的频率精确性，价格稍高,Dead Spots&Phase Nulls,盲点和零相位,Filing Cabinets,文件柜,Foil Backed Insulation,背衬金属膜的隔断,Mirrors,镜子,Metal Ductwork,金属管道,Anything That Can reflect signals,任何会反射信号的物体,Multiple Signals That Reach The Receiver At The Same Time Can Cause A Phase Null,多路信号同时到达接收机会导致零相位发生,Receiving Information,接收信息,Determines the overall range of the system/,确定系统的接收范围,Superheterodyne Receiver converts the carrier frequency to a lower one and filters out unnecessary noise./,超外差接收机将载波信号转换为低频信号并过滤掉无用的噪音,Spatial Diversity to help eliminate phase nulls&dead spots./,空间分集技术有助于消除零相位和盲点,Does Not respond To Noise Or Interference From Outside,Sources/,不会对外部噪音和干扰有反应,Learn Mode Technology,读取模式技术,Unique ID number assigned to each device at the factory/,出厂时每个设备已被分配唯一的,ID,编号,During system programming the control panel,Learns,the specific device(ID number)into its memory/,主机编程时读取特定设备的,ID,至内存,The device ID number is part of the 58-bit word data pack/,设备的,ID,编号是,58,位射频数据包的一部分,When A Sensor Transmits,无线探测器发射时,It tells the receiver it is an ITI transmitter/,向接收机报告它是,ITI,无线设备,Sends a sensor ID number/,发送探测器,ID,编号,Tells the receiver what device type it is (Door/Window,Smoke,Motion etc.)/,报告它的探测器类型,Gives the status of the sensor/,报告探测器状态,Indicates a low battery if necessary,/,如有则报告电池低电压,When A Sensor Transmits(Cont.),无线探测器发射时,(,续,),8 rounds of data when sensor is activated/,探测器触发时发送,8,轮数据,8 rounds of data when sensor is restored/,探测器复位时发送,8,轮数据,3 supervisory rounds every 64 minutes/,每,64,分钟发送,3,轮受监视报告,Sensors must check in within a prescribed amount of time to satisfy the panel/,探测器必须在指定的时间内在主机签到,Individual Point ID,独一无二的定位,ID,Every sensor is its own zone,so/,每个探测器占用独立的防区，因此,Dispatch the fire department to the exact room/,消防人员会直达起火的房间,Dispatch police to the exact entry/,Service technician knows location of problem prior to service call/,在用户拨打维修电话前，技术人员就已经了解问题所在,Wireless System Integrity,无线系统完善,Supervised-all devices report to the panel at a programmed interval/,受监视,-,所有设备按预设的间隔向主机发送报告,Low Transmitter Battery-each device monitors its own battery and when low sends the appropriate signal to the control panel/,低电压,-,每个设备监视自己的电量，发现低电压时发送对应信号给主机,Sensor Contention-each device transmits on a different timing interval to prevent signals c
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