The quaternary infrared detector uses a light-sensitive element that triggers an alarm only when each detector detects a signal. It has stronger anti-false alarm capability and better detection performance than ordinary binary infrared and curtain detectors. Intrusion direction recognition capability, the user breaks into the warning zone from inside to outside, and does not trigger an alarm. Only an illegal intrusion will trigger an alarm from the outside, which greatly facilitates the user to operate in the fortified warning zone without triggering. The alarm system truly realizes “zero false positivesâ€. And its peripheral devices are few, saving space and cost and debugging time, improving the reliability of the whole machine. l infrared acquisition module The infrared detector is a kind of radiant energy converter, which is mainly used to convert the received infrared radiation energy into other forms of energy such as electric energy, heat energy and the like which are convenient for measurement or observation. The binary detector consists of two units that are connected in reverse polarity to the common FET output, but the quad detector consists of four units, two outputs, which allow the signal processing to avoid false alarms. It features low noise, high responsivity, excellent common mode balance for a dual unit type, various filter windows for wideband or narrowband applications, single or dual channel devices, and unit devices with thermal compensation. Here, the quaternary infrared detector model Lhi807 is used, and its reliability and other indicators are far higher than the dual detector. 2 signal processing module The quaternary infrared detector provides a multi-segment detection zone. An alarm signal is generated by the accumulation of all infrared energy in each zone. It divides a human target into 4 to 8 regions to produce clear and strong signals for stable detection. Changes in local temperature, such as temperature changes caused by mice and curtains, affect only one or two regions at the same time, resulting in a smaller detection signal. These signals are then analyzed by the signal processing circuit to obtain a more accurate detection and to filter out false positive signals, as shown in Figure 1. Signal sampling affects the practical application value of the signal processing accuracy. In this case, Ni company TI5000 series DSP5402 is used, which is packaged in 68-pin PLCC with a 10-bit A/D converter inside, so the hardware circuit is omitted. The A/D converter can also achieve higher resolution. 3 overall hardware circuit The hardware part of the system is mainly composed of front-end input circuit, sampler signal processing and peripheral circuits. The overall circuit is shown in Figure 2. Oval Series Sensor Automatic Dustbin Auto Trash Can,Oval Series Sensor Automatic Dustbi,Oval Series Sensor Dustbin,Oval Series Sensor Office Dustbin NINGBO ZIXING ELECTRONIC CO.,LTD. , https://www.zixingautobin.com
