ZTE Aids Launch of China’s First Cross-Sea High-Speed Railway Between Fuzhou and Xiamen

On September 28, 2023, China’s first high-speed cross-sea railway, designed for speeds of up to 350 km/h, was put into operation. This high-speed line connects Fuzhou, the provincial capital, with Xiamen, a deputy provincial city. Spanning a total length of 277 km, it traverses mountains and seas, and is a key route in China’s “eight vertical and eight horizontal” high-speed railway network.

To meet the high-speed and efficient operation requirements of the railway, constructing robust communication systems is crucial. The communication system plays a role similar to that of the nervous system in the human body, ensuring the rapid transmission of information and maintaining system stability and security. ZTE uses a full-system redundancy communication solution to ensure high reliability and service continuity. This approach addresses challenges in network optimization in cross-sea bridges and complex cross-parallel scenarios, facilitating successful project delivery.

Full-System Redundancy Guarantees Secure Railway Operations

The GSM-R system carries key control commands in the train control system. Once a fault occurs, it may result in reduced train speed or a complete stop. In severe cases, a fault could disrupt the entire railway system, leading to significant losses in railway transportation. For network design, ZTE uses a single-layer interleaving redundancy coverage solution as the primary method and a same-site redundancy coverage solution as the secondary method. This ensures that the failure of any site on the line does not affect overall network performance. Regarding system equipment, ZTE employs an all-system redundancy and high-reliability solution. All boards, including BSC and BTS, implement redundancy through hot backup or resource pool backup to ensure secure and stable operation of communication equipment and reliable railway operations.

Meeting Delivery Challenges to Ensure Smooth Project Launch

The high-speed railway project from Fuzhou to Xiamen features China’s first redundant network, including a 10-kilometer cross-sea bridge and up to a dozen complex cross-connection scenarios, presenting significant challenges for project delivery.

First, the difficulty lies in optimizing the network for cross-sea bridges. The railway crosses three bays: Meizhou Bay, Quanzhou Bay, and Anzhou Bay. Both the Meizhou Bay and Quanzhou Bay cross-sea bridges are nearly 10 kilometers long. The communication network on these cross-sea bridges is intricate, involving high-antenna sites at the bridge heads and low-antenna sites on multiple bridges, creating a co-cell network.

Considering the safety of high-speed railway operations, antenna for communication equipment cannot be installed independently. They must be mounted on the existing four-meter-high columns on either side of the railway, with each site providing a maximum coverage distance of 2.5 kilometers. This network architecture makes it prone to multi-path interference and poor uplink and downlink quality in high-speed scenarios, which presents great challenges for acceptance tests and project delivery.

During the dynamic test phase, the delivery team continuously optimized the network based on the test results from daily dynamic inspection vehicles, addressing each test issue as it arose. By repeatedly adjusting the coverage and network optimization parameters of each site, the team effectively resolved complex problems such as multi-path interference and poor signal quality, ensuring a smooth acceptance test.

Second, multiple sections of the high-speed railway intersect with existing lines, which poses challenges for networking. Eleven sections (about 213 km) are involved. For the complex scenario of the high-speed railway from Fuzhou to Xiamen, the Nanchang Railway Bureau and ZTE’s professional team conducted thorough research and analyzed the cross-connection areas one by one. To ensure network performance in these areas, they adjusted networking solutions, shared sites with existing lines, modified regional frequency planning, and optimized signal coverage and neighbor cell relationships. Each cross-connection area was specially analyzed, and a tailored network optimization solution was developed. Finally, a specialized cross-connection network optimization solution for the high-speed railway from Fuzhou to Xiamen has been established.

With the efforts of the delivery team, the communication system for the high-speed railway from Fuzhou to Xiamen was successfully delivered and put into operation. After strict acceptance tests, all network indicators met the requirements, and the stability and reliability of the communication system were fully validated. This ensures a robust foundation for the safe and efficient operation of the high-speed railway between Fuzhou and Xiamen.

Creating a One-Hour Living Circle Between Fuzhou and Xiamen

After the high-speed railway between Fuzhou and Xiamen is put into operation, the travel time between the two cities has been shortened to less than one hour, creating a "one-hour living circle". Additionally, the "Golden Triangle" of Xiamen, Quanzhou, and Zhangzhou has been connected within a half-hour transportation circle. This will enable the southeast coastal city cluster of Fujian province to be linked into a "golden tourist belt".

The Fuzhou to Xiamen high-speed railway project is another successful delivery by ZTE in the railway sector. ZTE’s GSM-R network has been widely used in railway systems, with nearly 100 successful GSM-R communications projects completed. These projects cover many key railway lines and sites across China, providing a solid communication guarantee for safe and efficient railway operations. As 5G-R technology matures, railway communications are entering in a new phase of technological advancement. As a leading provider of communications equipment, ZTE has conducted extensive research and experiments in the field of 5G-R technology. ZTE will continue to leverage its expertise in railway communications to offer more advanced, efficient, and secure communication solutions for the industry.