As carriers turn 'frenemies', downloads quicken in rail tunnel

It is never easy to ensure stable telecom signals for passengers on bullet trains. When it comes to the high-speed railway in the mountainous Yunnan province, the task is even more challenging.

But in November, 2016, employees at China Tower Corp announced that they had managed to ensure 95 percent coverage of telecom signals for a section of the Shanghai-Kunming railway.

Their secret is to let the country's top three mobile carriers share as much telecom infrastructure as possible. Along the 192-kilometer high-speed railway section, of which tunnels account for 30 percent, the company has built 405 towers for China Mobile, China Unicom and China Telecom.