NTT DoCoMo Inc. announced that it began testing an experimental Super 3G system, so-called 3.9th-generation mobile transmission standard, in July 2007. The company will seek to achieve the maximum downlink transmission rate of about 300 Mbps.

NTT DoCoMo will begin an indoor experiment to test the wireless transmission performance of Super 3G with the newly developed test equipment. The experiment will be initially focused to confirm its basic performance by using a setup including one transmitting antenna and one receiving antenna, which serve as the base and mobile stations, respectively.

Then, the company will expand the experiment to examine the Multiple-Input Multiple-Output (MIMO) technology by employing up to four antennas. The antennas will be used for both the transmission at base stations and the reception at mobile stations with a view to achieving the maximum downlink transmission of about 300 Mbps.

Also to be examined are the handover function between two base stations, voice and image transmission, and various applications such as gaming. Results of these experiments will be reflected on the development of the commercial Super 3G system, which is expected to be completed in 2009.

The Super 3G system is a highly advanced version of HSDPA and HSUPA, which have been evolved from W-CDMA. The system allows a higher data transmission rate, lower connection latency and improved spectrum efficiency.

The 3GPP, a standard-setting organization for the W-CDMA, is currently discussing standardization of Super 3G. Detailed specifications are expected to be finalized in 2007 under the international standard name Long Term Evolution (LTE).

In line with the progress in standardization, NTT DoCoMo, in July 2006, began accepting proposals from manufacturers seeking to develop the Super 3G equipment and has since promoted the joint development.