NTT DOCOMO, has launched of Xi (read “Crossy”), Japan’s first Long Term Evolution (LTE) service. LTE service initially will be available in the Tokyo, Nagoya and Osaka areas, with other major cities and regions to be added thereafter. Last month operator had announced the launch of LTE on December 24, 2010.

According to the operator, the LTE service delivers downlink speeds of up to 37.5 Mbit/s and uplink speeds of up to 12.5 Mbit/s. Xi will enable mobile data communication at a maximum downlink speed of 75 Mbps in certain areas. DOCOMO initially will sell Xi data terminals for connection to mobile computers, beginning with the USB-type L-02C.

LTE Voice calls will become possible sometime starting in April 2011, when DOCOMO will begin launching LTE-compatible mobile phones.

At launch, two data-only billing plans are being offered: “Xi Data Plan Ninen” and “Xi Data Plan.” Xi Data Plan Ninen, which will require a two-year contract, is a highly affordable plan costing between 1,000 and 6,510 yen for up to 5 gigabytes (GB) of data per month. Over 5 GB, 2,625 yen will be charged for each 2 GB.