NTT DoCoMo, Japan's largest mobile operator, is building a fleet of truck-based LTE base stations that can be deployed during natural disasters or to support large crowds.
The company said the trucks will provide mobile coverage that supports data downloads of up to 75 megabits per second (Mbps). Some of them will eventually be upgraded to support speeds of 112.5Mbps.
DoCoMo put the first of the trucks into service on Sunday, and plans to have a fleet of 30 up and running by the summer of this year. The company already operates a fleet of 50 trucks to support its older 3G network called "FOMA."
Each of the new trucks supports two large antennas that can be used to create networks from scratch or add capacity to existing networks.
Japan's mobile networks often go down after the country's frequent earthquakes and other natural disasters such as heavy rain and typhoons. Consumers pay close attention to which firm's networks are considered to be the most robust, and the firms all maintain trucks and equipment to quickly establish network connections. DoCoMo's rival Softbank uses helium-filled balloons to set up emergency relay systems.
All three of Japan's major carriers now offer LTE, or Long Term Evolution services, but DoCoMo launched first in 2010 and is eager to protect its reputation for having the most stable network. The carrier's service is sold under the "Xi" brand, pronounced "Crossy," and now has over 10 million subscribers.
The companies also compete to provide coverage at crowded events like the summer fireworks festivals that take place across the country and one-time events like large concerts. Mobile base stations are a cheaper alternative to building permanent infrastructure for remote locations.