Japan’s largest mobile operator NTT DoCoMo has thrown down that country’s first challenge in the 5G war, announcing plans to launch a commercial service on March 25. The move comes as Japan’s mobile telecom market is set for an explosion of 5G launches and welcomes in a new nationwide competitor.

DoCoMo’s network will have 500 base stations covering around 150 “locations” around the country at launch with plans to expand to all prefectures by June. The expansion will then hit 500 cities over the next year and scale up to 20,000 base stations over the next two years.

The carrier is touting initial downlink speeds of up to 3.4 Gb/s that will then increase to 4.1 Gb/s over the next several months. In an extensive and colorful presentation, it also cited the mobile edge computing (MEC) aspects of its network launch that tie into its Open Innovation Cloud platform and a recent proof of concept (PoC) that it initiated with MobiledgeX. This are focused on virtual reality (VR), augmented reality (AR), and mobile gaming applications.

DoCoMo’s network will also tap into past work the carrier has been doing with vendor partners. Last year it began using 4G LTE and 5G base station equipment compatible with the Open Radio Access Network (O-RAN) Alliance as part of a “pre-commercial” 5G service launch. The equipment was supplied by Fujitsu, NEC, and Nokia.

The launch timing maintains a previous commitment Japan’s mobile operators made last year. That included plans for the four nationwide operators – DoCoMo, KDDI, SoftBank, and Rakuten Mobile – to invest a combined $14.4 billion in their networks through 2024. DoCoMo carries the largest burden of a promised $7.1 billion in investments.

Japan’s regulators have effectively banned Chinese vendors Huawei and ZTE from the country’s 5G networks. SoftBank, which selected Ericsson and Nokia as its 5G vendors in May, is in the process of replacing Huawei equipment used in its 4G LTE network. KDDI has said it will use 5G equipment from Ericsson, Nokia, and Samsung for its network that is scheduled to launch this month.

Japan’s three legacy nationwide operators are all set to begin rolling out their initial 5G services over the next several weeks. The new entrant – Rakuten Mobile – is set to launch a 4G LTE service on April 8, with its 5G network to follow later this year. The service will rely on a combination of the carrier’s own equipment that relies heavily on virtualized infrastructure and a roaming agreement with KDDI that runs through March 2026.

The country’s launch timing also aligns with the upcoming 2020 Summer Olympics in Tokyo that are scheduled to begin July 24. That sports-hook echoes what South Korea’s mobile operators did by showing off early 5G networks during the 2018 Winter Olympics in Seoul.