Application of sun-Sea Optical Fiber Transmission Technology in HD Monitoring System

With the rapid development of video monitoring technology, the customer's requirements for video monitoring products are constantly increasing. The functional requirements are more complete and stable, and the performance requirements are clearer and more accurate. At the same time, how can we see a person's facial features in shopping malls, banks, and other important monitoring sites? How can we find out the license plate of a high-speed vehicle? How can we quickly and accurately find the target in crowded railway stations, stadiums, squares, and other occasions ......? These are all problems that need to be solved by video monitoring products. "Let's see more clearly", which is already a very urgent requirement raised by many users when using video surveillance systems.

A typical video monitoring system consists of front-end devices and backend devices. The backend devices can be further divided into central control devices and sub-control devices. Front-end and back-end devices are composed of multiple methods, and the connection between them can also be called a transmission system. They can be achieved through coaxial cable, optical cable, wireless or microwave. The video transmission system is the system's image signal path. A sound video transmission design is a very important part of the video monitoring system. If a well-built system selects cameras, lenses, monitors, and video recorders that can produce or process high-quality images, but does not have a good transmission system, eventually, the images seen on the monitor will not be satisfactory. According to the "barrel rule", the final image quality will depend on the worst part of the entire system, which is often the transmission system. System designers and installers must select the appropriate transmission mode, high-quality transmission cables and equipment, and install them according to professional standards to achieve the desired transmission effect.

The monitoring system transmission technology mainly includes video baseband transmission, optical fiber transmission, network transmission, microwave transmission, twisted pair wire balanced transmission, and broadband common cable transmission. Each transmission technology has its own characteristics and has its own application layer. For a complex monitoring system, different transmission modes are used according to different transmission distance and different monitoring requirements. Video baseband transmission is the most traditional television monitoring transmission method. It uses direct modulation technology and 8 MHz bandwidth at a baseband frequency) to directly transmit analog video signals through a coaxial cable. Its advantages are: low loss of image signal transmitted over short distances, and low cost. The disadvantage is that the transmission distance is short, and the high-frequency components above 300 m have a high attenuation, which cannot guarantee the image quality. A cable must be provided for a single video signal and a cable must be provided for the transmission control signal; its structure is a star structure with large wiring capacity, difficult maintenance, and poor scalability. However, fiber-optic transmission is the best solution for long-distance video monitoring and transmission systems, by converting videos and control signals into optical signals for transmission in optical fibers. Optical Fiber Transmission has a series of advantages, such as low attenuation, high frequency bandwidth, no electromagnetic interference, light weight, and good confidentiality, it is widely used in national and provincial-municipal backbone communication networks, cable TV networks, and high-speed broadband computer networks. In the video monitoring system, optical fiber transmission has become the preferred method for transmitting long-distance video and audio and control signals. However, optical fiber transmission requires dedicated technical personnel to be responsible for optical fiber fusion and equipment maintenance. In addition, it is not economical to transmit close-range monitoring signals.

Design of sun-Sea Optical Fiber Transmission System

In today's high-definition monitoring and video system applications, optical fiber cables are the best way to provide bandwidth performance in all connection modes. When using an optical fiber transmission system, the image quality of the system is limited by three factors: Camera, environment, and monitor. The optical fiber transmission system can transmit the image to a very far place without any form of distortion of the signal, and does not compromise the definition or details of the image. At the same time, the development of surveillance video is based on the use of IP digital technology, so as to take advantage of the low cost of the Ethernet network system and the advantages of digital transmission technology, it also has the ability to expand and interact with other security systems.

In an optical fiber transmission system in a large park, if two or more buildings need to be connected, an outdoor optical fiber cable is usually laid between buildings. It consists of trunk cables, distribution cables, optical fiber transfer boxes, optical fiber cable distribution devices, and jumpers connecting buildings. During the planning and design of the scheme, the optical fiber cables used are divided into Outdoor optical fiber cables and indoor optical fiber cables Based on the interrelated characteristics of the buildings, if two or more buildings are connected through a podium or aisle corridor, the user's internal optical cable can be used. Otherwise, an overhead or embedded outdoor optical cable must be used for connection. The optical fiber transmission system is the lifeline of the entire monitoring system.

At the same time, in the construction of the actual optical fiber transmission system, in order to achieve the connection, allocation and scheduling between the trunk cable and each optical distribution node, to provide secure, reliable, flexible, and mobile optical fiber and optical fiber management equipment for the monitoring Transmission System, Optical Fiber Connection boxes are used in many areas. The optical fiber junction box is a type of junction equipment that provides end-to-end and jumper for the main optical fiber cables and wiring cables. After connecting the trunk cable to the cabling box, the trunk cable and the cabling cable are directly connected by Optical Fiber jumpers after fixing, splicing, and wiring.

The diversity and complexity of the network topology will inevitably increase the number of optical cables. The traditional solution will lay new optical cables between buildings, but this solution will increase the construction volume and increase user investment. In this case, we can consider using optical fiber "crossover" to achieve optical fiber connections between different buildings. The optical cables connecting different buildings can be connected to the same building at the same time, and a fiber jumper is used in the optical fiber junction box for the most flexible connection.

Optical fiber crossover 

Cross join

It can be seen that although the cross-connection method adds a connection point, the management convenience and reliability of the cross-connection are incomparable. The optical fiber cables connected to the two ends are fixed and considered as permanent connections. To move, add, and replace the patch cord, the maintenance personnel only need to change the Jumper between the distribution frames. Cross-connection is undoubtedly the best choice for the core of the transmission system, which regards fast recovery, reducing misoperations, and ensuring the normal operation of device ports as the most basic requirement. After all, it is wise to avoid using sensitive device ports during routine maintenance. Only the cross-connection method is the most reliable, flexible, and persistent connection method. Through the cross-connection mode, users can be reduced, and flexible allocation and scheduling functions can be achieved. The Network Mode of the Ring Network and star network can be used, and the network mode is flexible, the actual usage of the improved optical fiber.

The optical fiber transmission system has the advantages of large capacity, long transmission distance, and strong anti-interference ability. It plays an irreplaceable role in communication and transmission. When transmitting video images remotely, it is best to use an optical fiber transmission system. When we need to transmit high-quality image images and do not want to reduce the image quality, we should first choose the optical fiber transmission system when designing a high-definition video monitoring system.

1. Brief Introduction to new breakthroughs in wireless video surveillance technology
2. Optical Fiber Technology pre-connection in cabling