This year CPSE Security Expo 2017 has a detail, the radar represented by radar + visual integration began to enter the booth of large companies, haikang booth, Dahua, institute 38 of CEC, which brings a signal? Today we share the radar in the field of security applications.
First, what is safety protection?
There are generally two types of safety protection. One is the perimeter protection. The main purpose is to establish a visible or invisible "protective wall" using infrared, electronic fencing and millimeter wave radar at the boundary of the protective area. When there is an illegal invasion which detected, the detector sends an alarm signal to deter the intruder and notify the security personnel to handle it in time.
The second category of security protection is regional security, which refers to the security protection of key items or buildings in a large area such as a factory area. Once someone or a vehicle approaches the target to be protected, the sensor can detect the abnormality and the control system issues alarm signal and notify security personnel to handle.
Before science and technology were sufficiently advanced, most places simply set up barriers (such as iron fencing, fence fencing, fencing, etc.) around the facades in order to prevent illegal incursions and arranged for personnel to step up patrolling. At present, criminals often adopt advanced science and technology and the criminal means are more complicated. Therefore, the traditional means of prevention have been difficult to meet the security needs of key departments and key units.
With the continuous expansion of market demand, a variety of perimeter defense technologies (such as infrared radiation program, video surveillance solutions, leaky cable solutions, vibration cable solutions, etc.) continue to emerge as an important part of security and social security made its due contribution. However, due to some objective factors, these technologies still have some shortcomings and they are unable to meet the requirements of the security system in the new situation. In order to meet the actual needs of customers, millimeter-wave security radar came into being. As a new security technology, millimeter-wave radar has the advantages of other technologies unparalleled in security protection, which has been favored by the industry users and rapidly popularized and applied.
Second, security solutions status quo.
Security system according to their scope and location, can be divided into two categories,perimeter security and regional security. These two types can exist alone or in combination, depending on the specific application environment. The function of perimeter security is to establish a closed "protection wall" along the boundary of the protected area. Once an illegal invasion occurs, the security system immediately alarms and prompts security personnel to handle it in time. While the characteristics of regional protection are "key" protection, the regional security surveillance system monitors the entire zone. Once a person or object approaches the key target, the system issues a warning.
At present, more perimeter security systems at home and abroad can be divided into the following types:
CCTV monitoring;
Light type: infrared shooting, laser shooting;
Cable type: vibration cable, vibration cable, leak cable;
Millimeter wave radar;
CCTV is an important safety precaution system, mainly composed of cameras, monitors, control platforms, video / playback equipment and so on. CCTV surveillance system is usually not as a means of real-time monitoring, but after the transfer video, trace clues to use.
In addition, by the ambient light, perspective, field of view, resolution and other factors, video surveillance technology security system requires other means of detection, in order to play a good performance.
The main shortcomings of CCTV surveillance systems are:
Unable to do real-time detection, it is usually to call the video afterwards and trace the clues.
Can not take the initiative to locate the invasion point;
Detection range is small, affected by the weather, light effects;
Alarm algorithm low reliability.
Light type security system, the infrared radio is the most primitive means of realization, its working principle is: in the detection area installed in pairs of sensors, send and receive, the establishment of a virtual protective wall, when an object through, blocking the infrared When the receiving sensor detects the light intensity changes, the output signal. To reduce the haze interference, some light-based security system will upgrade to infrared laser, the effect has been improved.
Light-based security system has a larger defect, there are:
False positive rate, birds, insects, falling leaves, swinging branches may cause false positives;
Small range of protection. Due to the linear propagation characteristics of the infrared / laser light type security system can only establish a very limited detection area, it is easy to be crossed by the intruder;
No distance capability.
Cable-type prevention system is currently more mature products, mainly vibration cable program, leak cable program, vibration cable program. Vibrating cables are mounted on metal rails to sense intrusion by sensing pressure and strain.
Eakage cable is usually buried about 1 meter underground, the appearance of no traces of hidden good. Both programs have no positioning function. When intrusion occurs, the intrusion point can not be determined in time, and measures can not be taken in time to stop the intrusion. In addition, since the vibration cable is sensitive to vibration and the cable tension varies with temperature, the false alarm rate is high and the maintenance cost is high. There are leakage of the construction of complex cable, the ground after the flood water system issues affecting the work.
Vibrating cable is a new product put into use in recent years, compared with the above two kinds of cables, vibration cable to distance measurement.
The company is located in:
Vibration cable is also installed on the fence, the downside is the protective area is small, easy to identify and bypass.
Millimeter-wave radar on the radio sensor is a new technology developed in recent years, the role of principle is to establish a pair of sensors with a certain width and height of the millimeter-wave radar wall, once the object through, can be detected immediately. The main drawback of the millimeter-wave radar to the radio sensor is that it can not provide information about the distance from the intrusion point, the beam is relatively fat, and the application range is limited. Affected by the weeds on the surface of the earth and the branches shaking, the weeds and branches need to be cleaned regularly.
There is no good solution for the regional security precaution system. By the camera, the camera field of view, the camera pointing and other factors, video technology can not provide real-time, all-region monitoring, image recognition automatic tracking alarm technology has great limitations, still can not achieve greater outdoor surveillance.
All in all, each of the above protection systems has advantages and disadvantages and none of them can solve all the
Third, the new millimeter-wave security radar.
Market demand can promote technological development. In order to make up for the above system deficiencies, millimeter-wave radar gradually into the field of security. As technology advances and device costs have fallen, the millimeter-wave radars originally used in the military are no longer a problem for security.
The working principle of millimeter-wave radar: The radar transmits electromagnetic waves continuously. In the detection area, the electromagnetic waves reflect back to the object. After the radar receives the signal, it goes through a series of processing to demodulate the distance, velocity and direction of the objects carried in the returned electromagnetic waves Information and output through the communication port, control host-driven lights, sirens and other equipment emits sound and light alarm signals, intrusion detection alarm.
The new millimeter-wave security radar uses advanced coherent pre-alarm radar technology to achieve the entire monitoring area without any interruption of the entire coverage, with small size, light weight, high reliability and distance blind spot small, no speed blind spot, high-range resolution , Good anti-jamming performance and so on. Compared with the infrared shooting system, security radar is provided with a certain height and thickness of the continuous millimeter wave radar wall, there is no possibility of drilling and jumping. Compared with the cable system, security radar can not only locate the intruding target, but also obtain the speed, direction, distance and angle information of the moving objects in the monitoring scene and monitor the gaplessly within 24 hours. And with a high-speed dome camera with a synchronous zoom laser fill light, target tracking can be achieved, not only can locate the intrusion point immediately, but also get good image information for security personnel to respond quickly to avoid accidents.
The advantage of a millimeter-wave radar is that a single radar can create a continuous millimeter-wave radar wall of sufficient width and height that any object with a given surface area can be detected across this millimeter-wave radar wall. The current practical millimeter-wave radar, detection range up to 1Km, for oil depots, oil fields, terminals and other large enterprises have a security system, the obvious advantages.
A series of millimeter-wave radar, millimeter-wave radar with regional monitoring capabilities, ----electromagnetic scanning surveillance radar, this type of radar has a transmitting antenna, multiple receiving antennas, the transmitted electromagnetic wave encountered in the measured target is reflected back to reach Different receiving antennas have time difference, through the receiver information solver, you can measure the measured position of the target information. This feature is very useful in the area of prevention and control, schematic diagram is as follows:
Another branch of the area detection radar is the---- mechanical scanning of millimeter-wave radar.The radar is a fixed-angle radar mounted on a continuous 360 ° rotation of the turntable, the control system-driven radar in a certain way in the required angle of rotation, to monitor the user specified area. Compared with the above-mentioned electro-scan area surveillance radar, the mechanical scanning surveillance radar has a farther detection range and a larger detection angle, and is precisely adjustable, which is very suitable for the security of large scene areas and the anti-smuggling of borders and coasts.
The main features of the millimeter-wave radar:
24-hour non-stop area detection in the detection area;
Multi-target simultaneous detection in the detection area;
Real-time output of the detection results for the system to schedule real-time video capture camera;
Not affected by haze, dust, light and light effects;
Not affected by the rain and snow weather;
NSR100W is a very cost-effective K-band single-base smart area security wave radar, detection range up to 160 meters (vehicle), the use of a high degree of complexity of the FMCW modulation mode, can detect the distance of moving targets, angle information, with more high range accuracy.
NSR100W uses advanced solid-phase all-phase technology, with high-precision angle resolution capability, the length of 160 cubic meters of space, the invasion of the target detection, alarm. Through the back-end signal processing and pattern recognition algorithms, effectively filter false targets such as trees.
Fourth, practical examples of applications
Tank depot monitoring
Oil depot is a high risk, a key production unit. Oil flammable, but also a high economic value, so the safety of oil depots is essential.
Scene surveillance radar for oil depot this place with high safety requirements. How it works: When there are suspicious persons entering the tank area illegally, the radar detects suspicious persons and will send the angle, distance and travel track to the control center and drive the camera to realize the video surveillance linkage through the extended linkage control module so as to quickly locate Alarm area and cast the video to the monitor. Radar and video linkage, after a series of processing, call the data in the database and display alarm coordinates specific location, while the police on the screen display the nature of the incident location, time, site plans and other information can be monitored in real time Control of the security situation within the region, the modern unit must have a complete set of intelligent alarm system.
Prison perimeter to prevent
Prisons, as places where prisoners of crime are held, are one of the most important aspects of social governance. It is very difficult to detain and manage. Once a jailbreak occurs, it will easily cause serious damage and impact to social order and stability. Therefore, strict security measures are the primary protection of prison management.
Perimeter defense radar can control the camera linkage, monitoring the wall within the warning line every 100 meters (depending on the site environment to choose different models) to install a radar around the use of millimeter wave radar detection principle to form a 100 meters long, 6 meters high, When the suspicious personnel enter the warning zone or cross the warning line, the radar measures the distance, direction and speed of the suspicious persons from the radar and sends them to the backstage control center via the communication network. The control center Solve the distance, speed and direction of suspicious persons from the radar, and control the power zoom lens of the camera according to the distance information so as to clearly capture the area where the suspicious persons are found. The control center at the same time with the monitoring center linkage, the relevant information sent to the control center, the software platform will automatically pop up the alarm electronic map, linkage video images, and in multiple designated monitors at the same time pop-up alarm location video screen, system and video Monitoring linkage and can monitor images in the area to automatically switch to the big screen.
Look forward to the future
Security radar is emerging on the security market a new technical means? Shenzhen Security Expo we just saw a microcosm, the current radar detection has been widely used at home and abroad, with high-definition digital surveillance PTZ, high-end perimeter security requirements the market provides more efficient solutions. In the airports, ports, oil wells, power grids, rail traffic, prison posts and other high-end perimeter security market has a mature and widely used in more civilian markets, radar detection and security has a broad market prospects. I believe the Shenzhen Security Expo just a starting point, security solutions based on radar will be the next highest technology point, let us look forward to!
