Application of microwave alarm detectors and passive infrared devices

The anti-theft alarm system is a system that uses physical methods or electronic technology to automatically detect intrusions that occur in the defense monitoring area, generate alarm signals, and prompt the on-duty personnel to the area where the alarm occurred, and display possible countermeasures. The anti-theft alarm system is an important facility to prevent accidents such as robbery and theft.

Once an emergency occurs, the location of the incident can be accurately displayed in the security control center through sound and light alarm signals, so that emergency measures can be taken quickly. The anti-theft alarm system, together with the entrance and exit control system, closed-circuit television monitoring system, visitor intercom system and electronic patrol system, constitute a security system.

The anti-theft alarm system usually consists of three parts: detector (also known as anti-theft alarm), transmission channel and alarm controller.

Alarm detectors are composed of sensors and signal processing. They are used to detect intruders. They are composed of electronic and mechanical components. They are the key to the anti-theft alarm system, and sensors are the core components of alarm detectors. Using sensors based on different principles, alarm detection devices of different types, different uses, and different detection purposes can be constructed.

(1) According to their working principles, alarm detectors can be mainly divided into many types, including infrared alarm detectors, microwave alarm detectors, passive infrared/microwave alarm detectors, glass break alarm detectors, vibration alarm detectors, ultrasonic alarm detectors, laser alarm detectors, magnetic switch alarm detectors, switch alarm detectors, video motion detection alarms, sound detectors, etc.

(2) Alarm detectors can be divided into active alarm detectors and passive alarm detectors according to their working mode.

(3) Alarm detectors can be divided into point-controlled alarm detectors, line-controlled alarm detectors, surface-controlled alarm detectors and space-based alarm detectors according to their detection range.

In addition to the above distinctions, there are other ways of classification. In practical applications, according to different usage conditions, different types of alarm detectors should be reasonably selected to meet different security requirements.

Alarm detectors are used as sensing devices to detect intruders' intrusion and various abnormal situations. There are many places that need security protection in various intelligent buildings and ordinary buildings. These places also have various security protection purposes and requirements according to actual conditions. Therefore, various alarm detectors are needed to meet different security protection requirements.

According to the actual site environment and the user's security requirements, the reasonable selection and installation of various alarm detectors can better achieve the purpose of security. If the selection and installation of alarm detectors are not appropriate, there may be security loopholes, and the strictness of security prevention cannot be achieved, which will give intruders an opportunity to take advantage of, thus causing unnecessary losses to security work.

The alarm detector is required to have anti-tampering and anti-destruction functions. When the alarm detector is damaged, its transmission line is short-circuited or broken, or its protective cover is illegally opened, it should be able to generate an alarm signal output; in addition, the alarm detector should also have certain anti-interference measures to prevent various false alarms, such as: anti-harassment by pets and small animals, and anti-false alarm interference caused by changes in environmental conditions.

The sensitivity and reliability of alarm detectors affect each other. Reasonable selection of the detection sensitivity of alarm detectors and the use of different anti-interference measures can improve the performance of alarm detectors. The use of different anti-interference measures determines the performance of alarm detectors in different environments. Understanding the performance and characteristics of various alarm detectors and reasonably configuring different alarm detectors according to different usage environments are the key links of anti-theft alarm systems.

Digitalization, wirelessization and integration are the technical development trends of anti-theft alarm systems

In order to meet the requirements of China's entry into the WTO/TBT (Technical Barriers to Trade Agreement), all anti-theft alarm products must pass 3C certification. By observing the new products launched by many manufacturers this year, it is not difficult to find the technical development trend of anti-theft alarm products:

1. More stable/reliable: For example, the detector needs to be resistant to RFI/EMI, lightning, etc. to adapt to harsh climates;

2. More diverse functions: such as the detector can be frequency-adjustable, anti-blocking, anti-spray cover, anti-destruction, etc.;

3. More exquisite and compact appearance: to meet the increasing demand for interior decoration;

4. More intelligent design: convenient setting/disarming, user-friendly operation interface;

5. More powerful networking capabilities;

6. More convenient scalability.

In fact, the above development trends are all based on the three core technologies of digitization, wireless and integration.

In general, the development trend of anti-theft alarm products in 2005 is that product technology will strive for breakthroughs under the premise of digitalization, wirelessization and integration. In the application market, it will move towards a more detailed direction - launching different products for different markets. Taking the fastest growing residential area application as an example, some manufacturers said that directional curtain + pet-proof detectors designed for residential areas, low-cost, simple to install, wireless network alarm systems suitable for home use, and residential intelligent security + alarm integrated system products will all be highlights. In addition to indoor/outdoor applications in residential areas and commercial buildings, outdoor applications such as airports, docks, farms, mines, and oil fields are still waiting for manufacturers to vigorously expand.