Satellite timing equipment (NTP clock server) application highway monitoring system
Satellite timing equipment (NTP clock server) application highway monitoring system
Especially in recent years, with the rapid development of my country’s economy, the need for expressway informatization has also shown the characteristics of high intelligence, high informationization, and high diversification. The number of designs is even more amazing, and many distinctive, Innovative projects.
The content of highway monitoring mainly includes two parts: highways and toll stations. Looking at the entire industry, we often face the following problems:
1. Why set up a networked monitoring system?
China’s highways started late, but developed relatively fast. However, due to the differences in the economic gap and the construction foundation of each province, the development of expressways in each province is not the same. However, the real-time update and sharing of video images and traffic flow data is generally recognized by traffic control departments in various places. Especially in areas that have already been digitalized, a unified networked monitoring system is needed to ensure the sharing and updating of data across the province.
At each monitoring point, the monitoring sub-center uploads the monitored data to the provincial center in real time. The provincial center performs statistical analysis and processing on the collected data and displays it in corresponding charts. The provincial center can realize the monitoring system of the sub-center and variable intelligence Traffic guidance equipment such as boards, variable speed limit signs, etc. are controlled to allow pedestrians to know the latest road condition information, and managers can also monitor road conditions in real time to achieve the unity of use and monitoring.
2. Highways are generally located in remote areas, how to build a safe and reliable monitoring system?
The expressway is the link between cities. It has the characteristics of large spatial span, harsh environment and relatively high maintenance cost. The most typical example is the US interstate expressway. Based on the above characteristics, highway video surveillance equipment must have the following characteristics, that is, mature technology, stable work, safe and reliable, cost-effective and highly informatized.
Combining with the market, it is suggested to adopt the method of codec plus optical fiber transmission after demonstration. Laying optical fiber on the extension of the expressway can transmit video and reverse control signals. The optical fiber has a long transmission distance, reduced signal attenuation, and economical price. It is suitable for long-distance transmission. Once the installation is completed, it can be used all year round, and it can effectively reduce the maintenance cost in the later period. It is also used for interconnection with other systems and networked monitoring systems. The completion of the project has a very large promotion effect.
3. How to realize the compatibility of new and old systems and different devices?
In the current development process of expressways, there are mainly analog monitoring systems and all-digital monitoring systems based on optical transceiver matrix. Moreover, the system and other supporting facilities in each area are different. How to realize the later expansion of the system and the networking of the superior system is a realistic problem we are facing. In response to these problems, advanced system solutions are specifically introduced, which can facilitate the transformation, upgrading and expansion of old road sections, realize unified compatibility with products of different periods, and realize mutual editing and mutual control with other manufacturers' equipment. In the design, the concept of modular design is adopted, and the concept of equipment virtual layer is introduced, which can be smoothly compatible with different types of products from multiple manufacturers, which protects the user's investment to the greatest extent and solves the system compatibility problem.
With the completion of new road section monitoring projects in various provinces and the gradual completion of old road section reconstruction, a comprehensive, reliable and practical networked monitoring system has become an inevitable choice. As the largest equipment supplier and system solution provider in the video transmission field in China, he has a deep understanding of digital network monitoring and played a pivotal role in the construction of Chongqing’s network monitoring system, helping partners to achieve regional video network monitoring .
The highway network monitoring system is to edit real-time video images of road sections, traffic flow data, road closure conditions, traffic accidents, weather data, environmental data in the tunnel, working status of various field equipment, various alarm abnormalities, and real-time information such as construction conditions. Summarize and upload it to the road section monitoring center, monitoring sub-center and provincial monitoring center in real time through the communication network. The provincial center conducts statistical analysis and processing on various collected data, displays it in tables and curves, and displays the working status of each field equipment with icons , And by issuing control instructions to the corresponding sub-center monitoring system, to control traffic guidance equipment such as variable information boards, variable speed limit signs, etc., so as to facilitate pedestrians to understand the latest road conditions, and enable managers to monitor real-time road condition information to achieve Unification of use and monitoring.
Full service networked monitoring system solution
As a pioneer of digital networked monitoring system, relying on strong technical research and development strength, according to the characteristics of the transportation industry, developed the second-generation digital video networked monitoring system-a full-service networked monitoring system solution, which integrates data collection, event analysis, system judgment, The linkage scheme of video synchronization switching and storage has the planning idea of unified management and realizes the design concept of centralized monitoring and distributed control.
Full service networked monitoring system solution
The system integrates functions such as digital video transmission, video management, video storage, and external network publishing. The EV701 central equipment has 4 service slots, which can insert and remove codec cards at will, and supports up to 8 channels of video and audio data. The EV702 field integrated access equipment using the H.264 coding standard integrates the cameras, domes, pan-tilts, variable information boards, alarm sensors and other equipment that were originally scattered in the field. It also supports the video and audio of the MPEG coding standard. Access. It can encode more than 2 channels of video and audio signals at the same time, and supports dual-stream transmission. D1 data is used for real-time viewing, and CIF data is used for storage and Web services (including external real-time image release and remote monitoring by managers). Possess the IP switch off function, reduces the pressure of the communication network. Distributed multi-level monitoring of road-level centers, regional centers, and provincial-level centers, with unified authority set by the provincial center, and centralized management.
Multicast network monitoring system solution
The digital video surveillance system overcomes the shortcomings of traditional video surveillance systems such as large wiring engineering, waste of fiber resources, and video signals that are prone to attenuation, distortion, group delay, susceptibility to interference, inability to network, and large limitations. The system solution has been widely used in the construction of Chongqing's networked monitoring system, and has achieved good results.
An integrated system solution that combines all equipment, functions and relationships into one. Real-time video data processing such as real-time compression, decompression, transmission, and synchronization. Through the computer local area network or wide area network connection, the collected field images are sent to the centers at all levels. The centers at all levels can call any channel of monitoring images according to their authority. During the image call process, the centers are independent of each other and do not interfere with each other, allowing multiple centers at the same time Call the same image, and operate the image according to the authority judgment.
Multicast network monitoring system solution
The upper-level center can directly control and watch the front-end monitoring node without forwarding through the lower-level center to realize the real monitoring center function. The system uses the virtual matrix software to switch directly to the transmitted data. Any image called in any way is only encoded and decoded once, and there is no re-encoding and re-decoding, ensuring the lossless transmission of video details. Centralized control and centralized management of all images in the system. Monitoring centers at all levels have unified technical solutions. The virtual matrix software specially designed and developed by digital video communication completely replaces the traditional hardware matrix and greatly saves investment. Compared with the traditional method, the overall budget can be reduced by up to 40%. Using multicast technology, the encoder simultaneously sends video streams to monitoring centers at all levels, greatly saving bandwidth. Using the IP switch function, only the video stream being monitored is transmitted in the link, and the existing bandwidth is reasonably used.
Advantages of highway monitoring system
1. Open design, easy to realize mutual editing, mutual solution and mutual control
Has been committed to technological innovation in the transportation industry. With a large number of equipment solutions to meet the individual needs of different customers, as a research and development-oriented company, Digital Video has adhered to standardized design and open structure for all equipment and products from the beginning of its establishment. Facilitate the different needs of users of new and old systems, and facilitate users to adopt different solutions according to actual needs, easy to integrate with third-party manufacturers' equipment and network management software, and have been widely used in the mutual editing and mutual solution of Chongqing City .
2. Distributed control, centralized management
The EV702 field integrated access equipment using the H.264 coding standard integrates the cameras, domes, pan-tilts, variable information boards, alarm sensors and other equipment that were originally scattered in the field. It also supports the video and audio of the MPEG coding standard. Access. EV702 is equipped with optical fiber communication board, no optical transceiver is needed, and it can be directly connected to optical fiber for long distance. It is connected into a ring through EV702 and has self-healing function. Can be centralized (road-level monitoring center), distributed (level monitoring centers) storage. Distributed multi-level monitoring of road-level centers, regional centers, and provincial-level centers, with unified authority set by the provincial center, and centralized management.
3. Make full use of existing resources to protect users' investment
The specially designed and developed virtual matrix software completely replaces the traditional hardware matrix and greatly saves investment. Compared with the traditional method, the overall budget can be reduced by up to 40%. Using multicast technology, the encoder simultaneously sends video streams to monitoring centers at all levels, greatly saving bandwidth. Using the IP switch function, only the video stream being monitored is transmitted in the link, and the existing bandwidth is reasonably used. At the same time, the 1U4/8-channel standard digital video IP codec of Digital Video can realize the digital video codec of 4 channels or 8 channels of analog video only with a 1U chassis. The device has a compact structure and high integration, which can save a lot of space and budget.
It is reported that the Ministry of Transportation plans to reach 70,000 kilometers of expressways in China by 2020, and the dependence on expressways will increase in the future, and the monitoring market of expressways will have a long journey of exploration. , I believe that in the near future, intelligent road transportation represented by highway informatization will no longer be a dream.