Basic overview of intelligent security monitoring system

With the advancement of China's reform and opening up, a group of intelligent buildings that are suitable for the needs of the information society and that are safe, efficient, comfortable, convenient, and flexible have risen. In order to prevent the occurrence and harm of all kinds of thefts and violent incidents and ensure the safety of buildings, life and property are not damaged, the setting up of intelligent security systems is necessary.

With the development of science and technology, new methods of crime have also put new demands on the security system. In the information age today, the protection of money, property, and personal safety is on the one hand, and there are a lot of important documents and data stored in computers. , more need protection. In an intelligent building, not only external personnel need to be guarded, but internal personnel also need to strengthen management; and certain important locations, objects, and important people also need special protection. Therefore, for a modern building, a multi-level, three-dimensional security system needs to be set up.

Security monitoring system rating

Relevant regulations "Safety Precautions Engineering Procedures and Requirements" GA/T75-94 "Safety Prevention System General Graphic Symbols" GA/74-94 "Civil Closed Circuit Surveillance TV System Engineering Technical Specifications" GB50198-94.

According to the above specifications, combined with the risk status of security precautions and the actual situation of the project, comprehensively determine the protection level achieved by the security system.

The type of security technical protection system:

(1) Perimeter alarm system; alert system of building exterior wall composed of glass breakage alarm devices; television monitoring system (image review system); intrusion movement detection alarm system; audio monitoring system (sound review system); strong light illumination system;

(2) Level and main configuration of safety precautions (divided into four levels) A. Four levels of protection and safety protection system. The switch and alarm shall be provided for the doors and windows of business premises (banks); Foot-operated emergency alarm devices and linked alarms; alarm signals should be sent to the security duty room and nearby agencies. B. The three-level protection security system is the same as the four-level protection system device; The space three-dimensional protection system is set up, and the space (indoor and corridor) intrusion detectors are set; The central control device has the function of auditing (recording), recording the occurrence of alarms. Time, staff also point; For the business room, the main channel set up television monitoring, alarm system and alarm network. C. Secondary protection safety protection system is the same as the three-level protection system device; TV monitoring equipment has automatic and manual switching function, multi-screen display function; one-to-one camera device should be set up for the implementation of the teller system Password control is controlled by a person to operate the alarm system to start and stop, arm, disarm, bypass, reset, etc.; control center equipment has wired, wireless and their mutual conversion function to ensure the alarm signal is accurate and sent to the relevant alarm department; conditional business The place has a population control system and implements access to information cards (access control system). D. First-class protective security system, the selected detector should have two or more intrusion detection systems consisting of different detection technologies; In the event of an emergency, lighting, recording, and recording should be started automatically. The entry and exit control system is set up to classify and grade the personnel of the main divisions through information cards; the central control room should be able to immediately identify the parts, nature (robberies, thefts, fires, faults, etc.) on the screen while receiving the alarm signals. Display, print, record, store alarm time, location, nature, and disposal plan. The rest is the same as the second-level defense system.

Level of security monitoring system

(1) External intrusion protection: This section is to prevent the intrusion of external unrelated personnel. Corresponding measures such as alarms, reviews, etc. must be set up for perimeters, doors, windows, passages, entrances and exits, and the criminals should be prevented from outside the region.

(2) Regional protection: This line of defense is to detect those who have illegally invaded this area and send the information to the monitoring center. The center will handle it.

(3) Target protection: This line of defense is the protection of specific targets such as safes and important rooms.

Security system structure

In today's technologically advanced world, it is no longer just the traditional precautionary facilities such as locking, standing guards, and sentinels. No matter how strong the lock can be opened, the sentient sentry also has time to fight. Today, intelligent anti-theft security systems are manufactured using modern computer technology, modern communication technologies, modern control technologies, and modern graphic display technologies (ie, 4C technologies). Each subsystem independently performs its functions, and at the same time, the subsystems are integrated into a single anti-theft system. The second body ensures the safety of the building and creates an excellent working and living environment.

1, entrance and exit control: control principle

The so-called entrance and exit control is the management of the outbound population. The system controls the appearance of various types of personnel and their actions in the relevant areas, often referred to as access control systems. The principle of its control is: According to the range of people's activities, in advance to make various levels of cards, or predetermined password. Install magnetic card identifiers or password keyboards at the relevant gate entrances, entrances, vault doors, archive doors, elevator doors, etc. Users must pass valid cards or passwords to pass or enter. The card reader reads the card password, which is decoded and sent to the controller for judgment. If yes, the door lock is opened, otherwise the alarm occurs.

The characteristics of cardholders:

(1) The password of the card can be canceled from the system at any time, not afraid of being lost, not afraid of taking away.

(2) The password of the card is time-based and can be set in advance.

(3) The cardholder's activities at all entrances and exits are recorded on the computer and can be printed and analyzed at any time.

(4) Save management staff. With a computer management system, all entrances and exits can be controlled in the control room. In this way, not only improve efficiency, save manpower, but also avoid human error and improve security.

Types of access control systems: optical cards, magnetic matrix cards, magnetic code cards, barcode cards, infrared cards, iron cards, proximity cards, and biological discrimination systems such as fingerprint machines, palmprint machines, retina recognition machines, and voice recognition Machines and so on. From contact cards to contactless cards, proximity cards ranging from 100 mm to several thousand mm are widely used.

The above-mentioned various cards correspond to various access control machines, and the access control machines mainly have a networked type and a non-networked type (independent type). There are single-door access control machines, as well as two-door and four-door, eight-door access control machines. This makes the application of the access control very flexible. With the access control machine there are magnetic switches and buttons. Several access controllers and access control system slave door controllers are connected to the main door controller. Access control and door controllers are controlled by computers. The power required for access control is usually DC12V, which is provided by the door controller. Generally, power supply AC220V50Hz/DC12V is provided near the controller.

Access Control System Locations: For comprehensive smart buildings, the location of the installation is roughly: important offices, vaults, bank operating rooms, central control rooms, communications, and weak motor houses.

2. Anti-theft alarm system

The role of anti-theft alarm: The anti-theft alarm system is to use the detector to guard the key areas and important places inside and outside the building. When an illegal intruder is detected, the signal is transmitted to the alarm controller: sound and light alarm, the address is displayed, and the relevant on-duty personnel are connected. After the alarm, take measures according to the situation to control the development of the situation. Anti-theft alarm system in addition to the above alarm function, there are linkage features. Such as: open the alarm site lighting (including infrared light), linked audio and video matrix controller, open the alarm site camera for strict observation, a series of television matrix controller: the monitor display image, video recorder, multimedia controller automatic or Manual operation and the like can all be used to review the sound and image of the alarm site to determine the nature of the alarm (illegal invasion, fire, malfunction, etc.) and take effective measures.

The composition of the anti-theft alarm system: The anti-theft alarm system of the intelligent building is responsible for the detection tasks of various points, lines, areas and areas within the building. It is generally composed of a detector, a zone controller, and an alarm control center.

(1) Detector: The detector is responsible for the detection of illegal intrusion by personnel, and an audible and visual alarm is issued in case of abnormal conditions. At the same time, information is sent to the area alarm. Switch: Switch is a basic, simple, economical and effective detector. Commonly used are: micro switch, reed switch two. Line connections are normally open and normally closed. The closing or opening of the switch causes the circuit to turn on and activate the alarm. Beam interception detectors: At present, more use is made of infrared radiation, which consists of infrared transmitters and receivers. When a criminal crosses a door or window or other protective area, it blocks infrared light and bows | In order to ensure the accuracy of such detectors, frequency and phase discrimination circuits must be configured. Thermal Infrared Detectors: Also called passive stereo infra-red detectors. It uses human body temperature for detection. As we all know, any object, because the surface temperature is different, will emit strong and weak infrared rays, that is, different wavelengths of infrared radiation. The body radiates a wavelength of about 10μm. This feature is used to make thermal infrared detectors. The pyroelectric type has the best sensitivity and response speed. Therefore, it is currently used more commonly. There are 7 to 15 nm wavelength band-pass filters. To shield non-human infrared wave, to ensure accurate alarm. Microwave object movement detector: The Doppler effect of the frequency difference between the launching of the moving object (including human) and the frequency difference of the reflected microwave device can be used to detect human invasion. Ultrasonic object movement detector: similar to the microwave movement detector, but the wavelength is different, the ultrasonic frequency is often above 20KHz. Detective-type mobile detectors: They must be used in a light-emitting environment. The principle is to use two photocells to form a differential detection device that can detect minute changes in ambient light. Glass Breaking Detector: It is a piezoelectric pickup that is mounted on the surface facing the glass surface. It effectively detects and alarms the high-frequency sound of the glass and has been widely used in door and window protection. (There are other types of detectors, omitted here.)

(2) Zone alarm: Usually, a zone alarm can accommodate input signals of 8 loops. After processing, the signal is sent to the video matrix switching controller of the TV monitoring system to realize linkage control. In the general system, the regional alarms ≤ 8 sets, that is, ≤ 64 loops. When there are more than 64 loops, the microcomputer-controlled alarm system must be used instead.

(3) Alarm Control Center: The alarm control center is usually co-located with the TV monitoring center. Its function is to check the working condition of the system through the control keyboard. The alarm of the emergency event can automatically pop up the alarm part on the monitor screen and record the time and address. At present, some products are equipped with an alarm input card in the center, with a capacity of 128 channels/block, which can be increased to 2048 points as required. The connection between the alarm plug-in card and the CCTV controller is the RS232 port.

3, closed-circuit television monitoring system

More and more television monitoring systems are used in security systems. It enables the management personnel to see the important locations inside and outside the building in the control room, provide visual effects to the security system, and provide monitoring means for the fire fighting, the operation of the electromechanical equipment in the building and personnel activities.

The basic structure of closed-circuit television monitoring system: According to the basic structure of functions can be divided into: camera, transmission, control and display and record four parts.

(1) Camera: The camera is an important part of the surveillance system. A large number of charge-condensed CCD (charge-cowpled device) cameras are used. Camera color is divided into black and white and color. Choose one according to its use and economic conditions. The target size of the camera is represented by 1/3, 1/2, and 2/3 inches. When selecting a lens, pay attention to the size of the two. The camera has PAL, NTSCK and SECAM three major systems, China chooses PAL system. When selecting a camera, illumination needs to be considered, and infrared lighting can be selected if necessary.

(2) Lens: The choice of lens in the design is as important as the selection of the camera. The basis for selecting the lens is the field of view and the range of brightness changes. At the same time, taking into account the size of the CCD camera, the relationship between them is: the field of view determines the lens with a fixed focal length or zoom, focal length to take a large focal length, what range of zoom to choose The change in brightness determines whether or not to use an auto iris lens. Sharpness: It is an important index of the lens. If you want to make the image clear, the resolution is high, that is, the number of black and white stripes that can be distinguished in the length of the unit is generally calculated by the formula:

N=180/h

N---- lens resolution (on line/cm)

h - Height of frame format (cm)

Usually 1/2" format 4.8x6.4(mm2)N=38 pairs/mm h=4.8mm

1/3" format 3.6x4.8(mm2)N=50 pairs/mm h=3.6mm

Lens size: There are currently 1,2/3, 1/2, 1/3 and 1/4 inch. The general lens and camera have the same size or lens size as the camera size. Focal length: The focal length of the lens and the target size of the camera determine the viewing angle. The target surface (camera target surface) is fixed, the focal length is short, the visual field is large, and the focal length is large, so the visual field is small. Use w•h to represent the width and height of the CCD target surface, and f is the focal length of the lens. You can obtain the viewing angle.

Qh=2tan-l(w/2f)(0) horizontal viewing angle

Qv=2tan-l(h/2f)(0) Vertical Angle

Luminous flux F: luminous flux indicates how much light enters the lens, is the ratio of focal length to clear aperture F=f/φF luminous flux (dimensionless); f-focal length (mm); φ----clear aperture (mm), lens The maximum F value is often specified in the specification, such as 6m m/F 1.4. The lens clear aperture is 4.29mm. Auto iris lenses are required for large lighting changes (eg outdoors).

In short, there are six factors that affect the camera effect: the size of the subject, the size of the subject, the distance between the subject and the camera lens, the focal length of the camera, the size of the optical receiver (target size), the lens, and the camera system. Resolution. Design should be considered comprehensively.

(3) Signal transmission

Transmission of video signals: transmission methods include general coaxial cable, balanced pair cable, cable television coaxial cable, optical cable, and telephone line, etc. The impedance of homemade SYV-75-2 to 75-33-2 is 750, and the capacitance is not greater than The attenuation at 76 PF/m at 30 MHz is not greater than 0.86 dB/m. Transmission of control signals: The control center needs to control the equipment in the field, and it is usually done through the device demodulator. Commonly used control methods are: communication coding control and coaxial video control. The former encodes the control signal serially: multiple control signals are transmitted on a single line. Its control distance can reach 1km, such as the middle plus amplification processing, up to 10km or more, such as the use of fiber optic cable, the distance will be farther. The latter mode is the coaxial video control mode, in which video and control signals are multiplexed with one coaxial cable. There are also two ways to do this. One is to modulate the control signal in a different home rate range than the video signal (50Hz to 4MHz), and then composite it with the video signal and transmit them to the scene and then split them apart. Tone). The other is the use of video signal blanking during the transmission of control signals. The first one is currently used.

(4) Display and recording: This type of equipment includes monitors, video recorders and video processing equipment. These devices are installed in the control room. Current monitoring system dedicated video recorders can be recorded in regular 80 minutes, up to 960 hours. In addition to the long time, the video recorder also needs a remote control function to operate the video recorder with a control signal.

(5) Video Switcher: With the use of video switchers, a small number of monitors can be used to view multiple monitoring points. Currently, the device has several inputs, one output, and several input, m output, which greatly improves the monitoring. Efficiency.

There is also a multi-picture splitter 2 which can watch multiple monitoring signals simultaneously on one monitor, and this technique is also commonly used in control centers.

4. Security function of parking management system

General smart building basement is equipped with a parking lot. It is necessary to automate the management of the parking lot. The function of the parking lot management system is roughly: out, population control, parking space orientation, camcorder appearance, characteristics, brand name, timekeeping Toll. The license plate image recognition system has a security function, which can prevent the occurrence of a car theft. When a user takes a ticket or uses a monthly ticket or stored value ticket, the computer will record the color image of the vehicle model and license plate number through the camera of the Population Department, and also record the number of the entrance ticket or monthly ticket or stored value ticket. When the user pays for the departure or ticket, the computer will automatically display the license plate, vehicle model, etc. of the vehicle owned by the holder of the vehicle number ticket on the display screen and the closed circuit at the same time as the license plate and vehicle model of the video left on the entry. On the TV monitor, after confirmation by the staff, the gate is automatically opened for release, and these images are stored on the computer hard disk for reference.

5, the elevator control system security features

For high-rise or super high-rises, the security management of elevator control systems is important. To some extent, it involves the safety of the entire building.

Security function: elevator floor control system. The elevators of the building are set according to the needs of the time period management, some elevators stop running after the shift, and other elevators run as required. Not all elevators in the running elevators are parked. Instead, they are parked on the floor of the floor with valid cards. This elevator is equipped with a smart card reader. The reader recognizes the valid card and the elevator reaches the relevant floor. Without a valid card, the elevator will not open the door, which effectively controls the floor space for personnel. This will ensure the safety of the building.

6. Patrol Management System

Intelligent Building sets up a patrol management system as required. Its role is that the security guards regularly visit the site and send the "inspection in place" signal back to the security center to show that the road to patrol is safe. If "the inspection is in place, if the signal does not return according to the time, there will be a sudden on the way. When the incident occurs, the security center will take measures accordingly.The patrol system is to install the patrol switch on the designated patrol point, and usually set the access control to meet the patrol requirements.

Smart Security System Implementation

The implementation of the security system should first determine the level of security protection in accordance with the relevant specifications and functional requirements of the building. On this basis, the security facilities on-site facilities should be arranged to determine the scale, type selection, installation and debugging, and 15f.

1. Access Control System

Access Control (Reader) settings: Set as required outside the door (including rooms, stairwells, passages, etc.) 1.2 to 1.3m away from the ground The type is generally a proximity card, depending on the importance of optional fingerprint type or countersink Type of access control, double-sided access control, single-sided access control (indoor set-out button). Slave controller: The connection device of the access control machine and the access control host can be connected with one, two, four, or eight access controllers as required. Select from controller power supply: AC220V50Hz/DC12V, l-5A. Main controller: The main controller consists of computer hardware and software installed in a central control room. It contains various control expansion boards, remote control program setters, on-board display boards, and data storage transfer modules. Patrol system reader: The reader (reader) is the access control (patrol switch). This section can be incorporated into the access control system. Elevator access control system: As mentioned earlier, readers are installed in some elevators, and valid cards can be used to access the relevant floors.

Special note: (1) The smart building can be implemented - cartoon access control, but also enter - cartoon consumer system. (2) The access control system should be able to automatically open the corresponding door in case of fire. Fire control unit can be used to complete this function.

2. Anti-theft alarm system

Various detector settings: Anti-theft Shuangjian detectors, passive infrared beam detectors, glass crushing detectors, various switches, etc. are arranged in building entrances, stairwells, elevator halls, doors and windows that need protection, and important offices as required. , important engine room and other places. According to different deployment environment, select different alarms and installation methods (such as wall-mounting, ceiling-climbing).

(1) Setting of sound review device: Micro monitor (electronic monitor) is installed in the place where sound review is required. Generally, the wall-mounting method is about 2m away from the ground, and the line between the monitor and the audio matrix box is mostly a two-core shield twisted pair cable. , Such as RVVP2 x 0.5mm2. There is an audio matrix box in the control center. RS485 interface is used between the box and the video switching/control host, and the twisted pair RVVP2×0.5mm2 is used.

(2) Alarm control center setting: In the small-capacity system (number of channels ≤ 64): Eight-way alarm interface box is usually set by partition, and eight boxes make the loop up to 64. Alarm head and alarm interface box, usually 3-core shielded cable, RVVP3 × 0.5mm2. Alarm interface box and video switch/control host use RS-485 serial interface, twisted pair RVVP2×0.5mm2. When the system ≥ 64 loops, there are two solutions:

One: Select large-capacity system, the system configuration 128 alarm input card, the system accommodates 8 to 16 alarm input cards, the capacity of up to 2048 road alarm. If not enough, you can combine multiple systems.

Second: Use the access control/alarm management system. System parameters: number of cardholders 65000; access control 16320; alarm zone (number of ways) 130560; alarm output 130560; local printer 225; alarm status screen 1020; and support for encrypted transmission technology between computers ... .... The connection mode between each device is RS-232/RS-485 interface, twisted shielded line RVVP2×0.5mm2.

3, closed-circuit television monitoring system settings

Camera settings: Select different cameras according to different environments and different installation methods, such as whether the camera is black and white or color, lens configuration options, a range of focal lengths, auto focus, aperture, focus is manually adjusted, fixed focal length, camera With the size of the lens, whether to set the PTZ, determine the installation method, whether to choose the ball type, hemispherical camera (size determination), select the wide-angle lens in the hall and the elevator car, the choice of camera protective cover, lighting fixture selection And so on vary with the function.

Camera (with lens) control: This is done by the controller decoder. There are many types of decoders due to their different functions, but they all control the movement of the PTZ, lens, and auxiliary equipment after receiving signals from the matrix host. There are two ways to connect the decoder to the matrix/control host: "C', type (coaxial control) and "D type" (twisted pair control). As mentioned above, coaxial control "C?quot; Due to the high cost of equipment and application of less. Twisted pair control "D type", RS485 controllable distance up to 3km. And this way can be used for optical fiber, microwave and other transmission methods.

Special note: The line of security monitoring system is generally installed in the corridor, the hall and the upper part of the room due to the installation location of the field equipment. Some close to the ceiling, and the coaxial cable and the twisted pair cable are also relatively cheap and L operation management is independent, so it is generally not appropriate to Building integrated wiring cables are used together. Of course, the transmission of other data and images is another matter.

Central Control Room Setup: For the convenience of security work, the general central control room is located on the first floor of the building along with the security department. Its equipment mainly includes: video matrix switching/control host, alarm interface box, audio matrix box, character generator, video recorder, main control keyboard, deputy control keyboard, audio and video surveillance equipment, multimedia terminals and power supply equipment.

Video matrix switching/control host, there are currently various input/output specifications, such as 8×2, 8×4, 16×6, 96×8, there are video 96 people/8 out, audio 96 in/8 out 64 Road alarm 8 control keyboard and so on. The oversized system has video 4096 in/4096 out alarm 2048, 32 keyboards switch/control host. In the design and installation implementation, leave margin, set the scale, and select equipment as needed. According to the alarm system input signal, the video master controller completes the PTZ control, camera movement control, lighting control, lens control, and linked audio and video monitors, video recorders and so on. The access control system uses the gateway to access the host to form a three-in-one integrated system of anti-theft alarm, television monitoring, and entrance and exit control. With the help of multimedia technology, a combination of information and communication capabilities and computer interactivity, intelligent building security system to ensure the safety of the building.

The above devices are organically combined, and audio and video monitors are generally set up on the "TV wall" and the rest are centralized on the console. The area of ​​the control room is determined by the system scale, the power supply is available, the temperature and humidity can be controlled, and the floor is equipped with an anti-static floor.