Japan to trial its own 4G Technology

While we were focussing on the battle between LTE and WiMAX having already forgotten about UMB, Japan has been working on its Next G of PHS called the XGP.

The news came to light in ITU Telecom Asia, which concluded recently.

PHS was popular in Japan earlier on because it was very cheap and easy to deploy in the old days when other technologies were expensive. The main drawback it has is that it is not easy to perform handovers so the calls may drop while in the subway.

PHS operator WillCom has won, one of the spectrum block in 2.5GHz band and is going to start trials next April in Tokyo, Nagoya and Osaka and offer 20Mbps of symmetrical data speeds using a 10MHz spectrum block. A full commercial service is scheduled for August 2009.

The service will be known as WILLCOM CORE (Communication Of Revolution and Evolution)

The technology behind is based on the PHS architecture of numerous microcells offering limited coverage, but will incorporate a new air radio interface based on OFDMA/TDMA/TDD methodologies. Kyocera and UTStarcom will manufacture the radio access equipment for XGP while NEC Infrontia and NetIndex are developing the data card modules for the service. Canada’s Wavesat and Israel’s Altair is supplying the baseband chips for XGP. Like LTE and WiMAX, XGP will support viable spectrum blocks.

But while LTE and WiMAX are based on increments of 1.6MHz for its carrier size, XGP has aligned itself with CDMA and supports increments of 1.25MHz carriers.

With a basic 10MHz carrier system, XGP will offer data speeds of 20Mbps, but future systems incorporating MIMO and SDMA (space division multiple access) will be capable of supporting maximum symmetrical data speeds of 100Mbps. At the same time, the technical description for XGP will support handoffs between base stations for users travelling at up to 300 km/h.

A good presentation from Willcom on XGP is available here.

PHS = Personal Handyphone System