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Perimeter Security Alarm

Feb 26, 2019

Perimeter Security Alarm


Perimeter intrusion alarm system is a kind of security defense system, which USES a variety of detection technologies such as electricity, magnetism and vibration to realize timely detection and alarm when external objects invade the defense area of the target.


Perimeter intrusion alarm system is an important part of technical prevention system and the first line of defense of security alarm system. With the development of the society and the progress of science and technology, a large number of social wealth, important military sites, important facilities, power stations, inflammable and explosive material warehouses, etc. need to be effectively prevented by perimeter intrusion alarm system to ensure their safety. Therefore, more and more attention has been paid to intrusion alarm system. But our country starts late in this respect work, because technical difficulty is big, investment is much, demand is not big, as a result the manpower that makes manufacturer and investment is not much.


In some important areas, in order to prevent illegal invasion and various destructive activities, the traditional preventive measures are to set up some (such as iron fence, fence, wire fence, etc.) barriers or barriers at the peripheral boundary of these areas, and arrange personnel to strengthen patrols. At present the criminal element USES advanced science and technology, crime means is more complex, intellectualized circumstance falls, traditional precaution means already hard suit the need of job of safe safeguard of key branch, key unit. Human prevention is often affected by factors such as time, region, personnel quality and energy, and it is also inevitable to have loopholes and mistakes. Therefore, the installation and application of advanced perimeter intrusion alarm system has become a necessary measure. Once an intruder is detected, an alarm can be issued immediately, as if an invisible "electronic fence" has been added to the perimeter wall of an important area to loyally guard key targets.


Infrared intrusion alarm technology


From market research and product summary, active infrared correlation detector has been the biggest market share of perimeter intrusion alarm system in main product, while the vulnerable to the terrain, fence, to the influence of outside factors such as climate has a certain rate of false positives, but because of its technology has developed more mature, the product price is relatively cheap, thus making civil markets, in particular, many users are willing to accept.


Although there is a large market for active infrared countermeasure products at present, the problem of false alarm caused by its technical defects is also obvious.


Active infrared intrusion alarm technology more be applied on the outside of the protective wall fence or building Windows, outside intrusion alarm technology and direction recognition generally combined with passive infrared technology, used for protection of buildings to channel more, such as residential balcony door, the technology can automatically identify the user through the indoor outside to play and return from outdoor and indoor, or directly from the outside into the room. If users from indoor to outdoor sports will not alarm, whereas someone from outside into the interior will call the police, but also give a allowed to return to set the length of time, not alarm, back and forth in the setting time of a set time limit automatically reply to alert, so as to make the perimeter prevention highlighted more humanized.



Pulse electronic fence intrusion alarm


Pulse electronic fence is a widely popular active defensive perimeter intrusion alarm system in European countries. The front-end wire draws lessons from the advantages of the high-voltage power grid, and is mainly composed of visible wires and warning signs, which has a deterrent effect on intruders. In terms of energy control, pulse voltage is adopted, which has a long pulse cycle and low energy and will not cause casualties.


The pulsed electronic fence alarm system consists of a front fence, an electronic fence controller and an alarm host. The electronic fence controller is responsible for outputting high voltage pulse of the front end electronic fence and detecting the alarm state of the fence. The alarm host receives the signal of the fence controller to realize the alarm, setting and removing defense and linkage control. The alarm host can be equipped with any alarm controller of any brand.


Pulse type electronic fence alarm system has the function of distinguishing accidental touch from forcible invasion. If someone accidentally touches the fence or other objects (such as branches) touch the fence instantly, it does not belong to true invasion. The system has the ability to identify without warning. Only when the intruder intrudes forcefully and climbs over the electronic fence, causing the system to break the line (open circuit) or continue to touch the line (short circuit) will the alarm be issued. Therefore, the alarm of the pulse electronic fence system has a certain intelligent function, and the false alarm rate is very low.



Microwave sensor intrusion detection alarm


Microwave sensor detection is not only a perimeter protection system but also an indispensable detection technology in other wired and wireless burglar alarm systems. The microwave non-physical protective net cast by it can effectively prevent the invasion of outsiders. However, the microwave wall can not maintain the stability of the signal for a long time. Moreover, when the microwave signal is disturbed, it is easy to cause false alarm.


In view of the special status of perimeter intrusion alarm system, new requirements are put forward for the corresponding hardware and software in the design of security system. In the formation of intrusion alarm systems, software, hardware, must adopt an open modular structure, make the whole intelligent security systems have compatibility and interoperability, must adopt some general international bus and interface, request system of high degree of standardization, to facilitate compatible with many related components of virtual instrument, and is convenient to modify, update, and upgrade. Among them, as the priority among priorities of perimeter intrusion alarm system.


The perimeter intrusion alarm system should be able to accurately and timely detect intrusion and send out alarm signals; The source of intrusion alarm signal, anti-demolition alarm signal and fault signal should be clearly and obviously indicated.


The intrusion alarm system should be able to carry out sound check, and the intrusion alarm system engineering combined with the television monitoring system should be able to simultaneously carry out sound check and image check. (it is important to note that the intrusion alarm system does not allow for false alarms.)


Perimeter intrusion alarm system can be combined with TV monitoring system and entrance and exit control system. When joint design with other systems, system integration design should be carried out, and each system should be compatible with each other and work independently. The priority of intrusion alarm is next to fire alarm.


The system should take preventive measures against all paths of the intrusion fortified area, and should take preventive measures against possible weak links of protection. As for the integrity problem, many alarm systems now have vulnerabilities, and the key is the lack of integrity concept in the design. To solve this problem, it is necessary to rely on professional designers to fully understand the standard content and accumulate rich experience in alarm engineering.


The design of intrusion alarm system should adopt the protection system of depth. According to the risk level and protection level of the protected object, the whole protection area should be protected in different regions and levels. A complete defensive area shall include four different types of defensive areas: perimeter, surveillance area, protective area and restricted area, and different protective measures shall be taken against them.


Although the perimeter intrusion alarm system is not the most invested system in the security system, it is the most widely distributed and the most important basic subsystem. In the linkage with video security monitoring and access control system, intrusion alarm plays the role of outpost. Therefore, in the three mainstream system integration modes, the integration with alarm host as the core is also a highly valued system construction mode. With the promotion of the safe city construction process throughout the country, the huge application demand of the urban network alarm and monitoring system construction as the main goal will promote the rapid development and further improvement of perimeter intrusion alarm system products, and form a rapid growth of the market prospect.