Alarm false alarm solution!

The main reasons for the false alarms in current monitoring systems are as follows:

1. Infrared alarms are inaccurate in the judgment of intrusion behavior, resulting in false alarms.

2. Infrared alarms are caused false alarms due to external environmental factors, such as temperature, light and other environmental factors; there are also air flow, pet actions and other factors.

3. Hosts and alarms use wireless encoding to set the encoding because duplicates cause the host and alarms to re-enter the code and cause false alarms.

4. The relatively poor anti-interference performance of wireless alarms is likely to cause false alarms due to the same frequency interference.

5, there are some alarm quality but off, such as component damage, poor production processes will cause false positives.

6, artificial factors can also cause alarm false alarm, such as the user's improper operation, accidentally triggering the alarm, accidental mistakes, mistakenly entered the defense zone will generate false positives; there are ways to install equipment, angle and position Inappropriateness can also cause false positives.

How to reduce false alarms

In general, the cause of false positives is very complicated. If you want to reduce the false alarms of burglar alarms, the most important thing is to consider them from many aspects. For example, the alarm is selected from the aspects of performance and technology. This includes the selection of sensor alarms, the external design of Fresnel lenses, microprocessor programs, multi-technology, automatic code-scrolling coding technology, production processes, and methods of use. , temperature compensation, sensitivity detection distance adjustment and so on. These combined factors determine the performance of the alarm and the incidence of false alarms. If the above factors can be solved, the performance of the alarm will be improved, and the false alarm rate of the alarm will be greatly reduced.

The design of a new generation of infrared alarms has made a series of improvements based on the above factors, and has adopted some unique technologies to improve the performance of the alarms to some extent. For example, in the focus of an infrared lens, two photothermal sensors connected by different circuits are applied. In this case, a special lens divides the coverage area into a plurality of protected areas of a trapezoidal sensitivity to ensure signal strength in the protected area. The unique lens also acts as an infrared filter, and the specially treated black lens on the surface allows visible and short-wave infrared radiation to enter and is absorbed by its black base. The black infrared lens reflects only the infrared rays whose wavelength matches the body's movement and reflects it to the photothermal sensor. Through the white light filter, the alarm can prevent white light interference. The alarm should detect the change of infrared radiation energy when someone enters or leaves the area covered by the alarm. The A/D converter digitizes the signal sent from the sensor. Then use the processor for analysis before sending out an alarm signal. After continuous improvement, the performance of the alarm has been improved. With constant changes in the environment, human factors and other factors, the alarm faced by the alarm is still very large, so the alarm still needs constant updating and improvement.

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