BEIJING, Nov. 13, 2024 /PRNewswire/ -- Recently, Jiangxi Branch of China Telecom (China Telecom Jiangxi for short) and Huawei jointly has built an F+T dual-layer premium network for the high-speed railway. Innovative solutions such as 2.1 GHz 8T8R AAU and 3.5 GHz wide-angle MetaAAU were adopted with the High-Speed Railway Superior Experience and High-Speed Railway Dedicated Network Enhancement features. After the solution has been deployed, the performance of 5G networks is significantly improved, allowing users on trains to enjoy smooth entertainment services such as live streaming, HD videos, and New Calling, as well as convenient office services such as remote calls and remote office.
China's high-speed railway mileage has reached 40,000 km. According to the 14th Five-Year Plan, the high-speed railway mileage will reach 50,000 km by 2025. High-speed railway scenario is a typical high-value scenario. Specifically, both the penetration rate of 5G terminals and DOU are high. Short video applications and voice/video calls via WeChat are most popular ones. In addition, 5G network construction on high-speed railways faces four challenges. First, the inter-site distance along high-speed railways is long. Second, the penetration loss in the high-speed railways is greater than that of general speed railways. Third, when a train moves at a high speed, the Doppler shifts increase, and the performance deteriorates. Fourth, the high-speed railway speed is 300 km/h, and the cell switching occurs every three to four seconds on average. As a result, the staying duration is short, and user experience is poor. How to achieve the premium coverage of high-speed railways through technological innovation is an important topic for China Telecom Jiangxi during its long-term exploration and practice.
The Yingtan section of the Shanghai-Kunming Railway in Jiangxi Province has deployed the innovative 2.1 GHz 8T8R AAU solution. As an innovative integrated AAU, the 2.1 GHz 8T8R AAU features multiple antennas, integrated high-gain arrays, intelligent beams, and precise and fast scanning. In addition, the 2.1 GHz AAU shares the same antenna with the 1.8 GHz antennas on the live network, saving space and rentals. The single-bit power consumption (power consumption/capacity) of the 2.1 GHz 8T8R is lower than that of the 4T4R. After the solution has been deployed, the onsite test results show that the coverage is improved by 5 dB compared with that of 4T4R. The average downlink and uplink rates in the entire section increase by 21.6% and 50% respectively, and the downlink and uplink rates at edges increase by 82.6% and more than 100%. After 8T AAUs are deployed, the total traffic volume increases by 89%; the 5G traffic distribution ratio reaches 52%, 13% higher than that of road sections where 4T is deployed. In addition to better coverage, capacity requirements are fully and obviously released.
In the Nanchang section of the Shanghai-Kunming Railway, the innovative 3.5 GHz wide-angle MetaAAU solution has been used in a 7-km section to provide continuous 3.5 GHz coverage with a longer inter-site distance. Since the average inter-site distance along the Shanghai-Kunming Railway is long, the traditional 3.5 GHz 8T solution cannot provide continuous coverage. In high-speed railway scenarios, to acquire new sites is often costly. Therefore, China Telecom Jiangxi and Huawei have jointly added 3.5 GHz wide-angle MetaAAUs to the existing 2.1 GHz single-layer network. With the innovative wide-angle MetaAAUs, continuous coverage in the road section with an average inter-site distance of 740 m and a maximum distance of more than one km can be realized. The 2.1 GHz + 3.5 GHz carrier aggregation (CA) large-bandwidth solution can also provide high-speed railway users with premium 5G experience in services such as remote conferencing, HD videos, and gaming. During the commercial deployment, the wide-angle MetaAAU has been deployed at the same site with the 2.1 GHz equipment on the live network to achieve continuous coverage. Thanks to the solution, the deployment costs are greatly reduced, and the deployment period of the 5G premium broadband network in the high-speed railway are shorter. According to onsite tests, 3.5 GHz wide-angle MetaAAU and 2.1 GHz CA can provide 100% coverage along the high-speed railway. The average rate has increased by 132%, taking a lead position in competition. Specifically, the average downlink rate is 40% higher, and the edge rate is more than twice. The 3.5 GHz wide-angle MetaAAU can also effectively alleviate the high-load issue on the 2.1 GHz equipment, making the user-perceived rate on the 2.1 GHz band increased by 93.7%. This also enables more users to enjoy the convenience brought by 5G smart travel.
After the High-Speed Railway Superior Experience feature is enabled, the signal frequency can be proactively adjusted to offset the negative impact of frequency offset. In addition, it has resolved the Doppler shift issue occurred in the continuous coverage of high-speed railways. After the High-Speed Railway Superior Experience feature is enabled for the Jiangxi section of the Shanghai-Kunming Railway, the call drop rate decreases by 75%; the user experience of the downlink rate improves by 50%, and the traffic increases by 20%.
After the High-Speed Railway Dedicated Network Enhancement feature is enabled, the number of inter-cell switches decreases. Furthermore, the staying duration is longer despite the frequent cell switching of the high-speed train, and the cell experience and capacity are improved as well. After the High-Speed Railway Dedicated Network Enhancement feature is enabled for the Shanghai-Kunming Railway, the access success rate increases to 99.2%, and both the experience and capacity increase by 50%. This resolves the problem of difficult access and limited capacity in ultra-high-speed scenarios.
In the future, China Telecom Jiangxi will continue to cooperate with Huawei in 5G innovation, explore 5G network construction requirements in diversified scenarios, and make contributions to building leading 5G networks and facilitating digital and intelligent transformation in Jiangxi Province.
