Ningbo Sunhon International Co., Ltd. , https://www.scooterelectricadult.com
A subway system consists of one or more lines, a control center, and one or more depots. Each line is about 10-20KM, usually 10-20 stations. Most of the communications are conducted at stations/depots and control centers. Various types of voice communications (scheduled phones, emergency phones), broadcasts, wireless systems, signal systems, power monitoring systems, check ticket systems, and environmental control systems form a communications and control network. Using the FR-6000 and FR-8000 product systems, the transmission of this system can be unified in a single, integrated system.
Application requirements of FR-6000 in subway transmission network
1) Adapt to high temperature, hot and humid environment, require transmission equipment working temperature: -20 ~ 50 °C Storage temperature: -30 ~ 70 °C, storage humidity: 5% ~ 95%, non-condensing.
2) The electromagnetic environment in the train is complex and the transmission equipment is required to have strong anti-electromagnetic interference capability and a long average time between failures.
3) It is required to have anti-vibration and anti-impact design so as to adapt to the vibration impact environment when the train is running.
4) In order to ensure the data security of remote monitoring, the transmission equipment needs intelligent and efficient network management functions.
solution
FR-6000 is an integrated network management system that adopts a master-slave management architecture. The network management card performs information collection and function control on the service cards on the rack. The remote network management function facilitates the status monitoring and function setting of the transceivers at the local office and the remote site, greatly reducing the daily maintenance workload and expenses and improving the service quality. On the basis of practical examples accumulated over many years by this network management system, we have introduced the FR-6101/02/04I series of remotely managed industrial grade fiber optic transceivers for the application of metro transmission networks. The intelligent central office network management platform also has remote industrial-grade specifications suitable for the metro environment. In addition to the industrial-grade configuration specifications, we have also added POE-powered functions to electrical ports to provide power supply capabilities for end-point devices in voice communications, broadcasting, and wireless systems, and to facilitate the transmission of various signals in subway transmission networks. The transmission network structure is more flat and the network management is more convenient.
Application diagram 
Application of FR-8000 in Metro Transmission Network
At present, the technical solutions for subway and other rail transit communication transmission systems mainly include: Open Transmission Network (OTN), Synchronous Digital Transmission System (SDH), and SDH-based Integrated Service Bearer Network (MSTP) in asynchronous transmission mode (ATM) ) Based on multi-service platforms, etc.
Take a subway communication system in a city as an example. There are 8 subsystems in this system, namely, OTN, PABX, RADIO, PA, and CCTV. Network Management (NMS) ) And uninterruptible power supply (UPS) and so on. The subway communication system composed of these eight subsystems not only provides various services for the city’s subways, including voice, television images, and data, but also provides control and data channels for the control and environmental control systems of subway lines. Therefore, the subway communication system is a communication link network that integrates voice, image, data, and control channels, ensures the provision of transmission services, provides information for passengers, and ensures high-level control of passengers at the station and on the vehicle, and guarantees. Their safety.
FR-8000 Advantages Explained OTN is an open fiber optic loop transmission network. Its biggest characteristic is that it can configure the transmission bandwidth according to user requirements through the network management. It has a rich user interface, can transmit broadband digital video and Ethernet information, and provides 1 +1 loop self-healing protection function, high network security. The OTN equipment is equipped with transmission system control collinear digital compressed video channels and interfaces. In addition to its internal network interfaces connected to other OTN networks, the OTN equipment also has SDH services, FC services, and CPRI services compatible external interfaces. Other networks are easy to connect.
Because OTN has the above advantages, China has got corresponding applications in Guangzhou Metro, Shanghai Metro, Chongqing Metro, and Nanjing Metro. It can be said that the application of OTN in subway has certain advantages.
solution
The optical fiber loop of the transmission system adopts a bi-fiber bi-directional channel protection method. In the subway, a loop network is assumed to be formed by the optical cables assumed on both sides of the tunnel, as shown in FIG. The nodes in the OTN network are interconnected by point-to-point fibers, and these fibers form two loops that are mutually loop-backward. 
The ring that transmits data clockwise in Figure 1 is called the primary link, and the ring that transfers data counterclockwise is called the standby link. In normal operation, all data is transmitted clockwise on the primary link, and the backup link is in backup state. The standby link is mainly synchronized with the primary link and monitors the primary link at all times. The working status of the road. In the event of a failure, he can quickly replace all services in transit on the primary link and automatically resume transmission to the primary link when the failure is fixed.
In actual subway projects, the distribution of each station is often chain-like. To form a loop, we use a jump link method to form a loop. as shown in picture 2
The FR8000 series is a transmission system developed for the application in the metro area. It considers all application requirements of the subway and integrates the interfaces and functions required for all services in the subway.
Modern communication transmission systems are not only used for traditional voice and data communication, but also widely used as a backbone transmission network for a dedicated control network formed by various industrial and traffic control systems. This requires the transmission backbone network to have high serviceability, high reliability and high availability in order to ensure that the control network formed on it can operate safely and reliably. OTN's ability to self-repair system faults provides users with a reliable transmission network. Therefore, in the subway project, it not only serves as a transmission backbone network for the communication system, but also provides a transmission channel for each vehicle control system and environmental control system, such as a signal system (point-to-point mode of RS422 card) and station equipment control. Systems (BAS, Ethernet), power monitoring systems (SCADA, point-to-point for RS422 cards) and automatic fare collection systems (AFC, point-to-point for RS422 cards) are all controlled using OTN networks as transmission channels. The internet.
A subway system consists of one or more lines, a control center, and one or more depots. Each line is about 10-20KM, usually 10-20 stations. Most of the communications are conducted at stations/depots and control centers. Various types of voice communications (scheduled phones, emergency phones), broadcasts, wireless systems, signal systems, power monitoring systems, check ticket systems, and environmental control systems form a communications and control network. Using the OTN network, the transmission of this play system can be unified in a single, integrated system. The OTN network is particularly suitable for subway systems due to its ability to withstand harsh environments (EMC/EMI/EFI), high serviceability of OTN networks, high reliability and high availability, and its flexible networking capabilities.
Metro transmission network solution
Shenzhen Guanglu Online Technology Co., Ltd. is a diversified high-tech enterprise that serves the communications industry, including technology development, technical services, production and sales. The existing FR-6000 and FR-8000 two product systems can be fully applied to the subway transmission network to improve the stability, reliability, and security of the network.