TOKYO, JAPAN, February 9, 2007 --- NTT DoCoMo, Inc. announced today that it achieved a maximum packet transmission rate of approximately 5Gbps in the downlink using 100MHz frequency bandwidth to a mobile station moving at 10km/h. The field experiment of fourth-generation (4G) radio access took place in Yokosuka, Kanagawa Prefecture on December 25, 2006.

After having achieved a maximum speed of 2.5Gbps on December 14, 2005, DoCoMo doubled the speed in the more recent test by increasing the number of MIMO* transmitting and receiving antennas from six to 12 each, and by using proprietary received signal processing technology.

As compared with the December 14, 2005 test, the frequency spectrum efficiency, or the ratio of data transmission rate to channel bandwidth, was also doubled from 25bps/Hz to 50bps/Hz (5Gbps/100MHz).

DoCoMo will present the details of the experiment at the 3GSM World Congress 2007 in Barcelona, Spain being held from February 12 to 15.

DoCoMo looks forward to contributing to the global standardization of 4G through its ongoing research and development.

*Multiple-Input Multiple-Output: Different data streams are spatially multiplexed using multiple antennas for both transmission and reception on the same frequency

Main Technologies of 5Gbps Packet Transmission Experiment

Achievements in 4G System Development

About NTT DoCoMo

NTT DoCoMo is the world's leading mobile communications company. DoCoMo serves more than 52 million customers, including 32 million people subscribing to FOMA™, launched as the world's first 3G mobile service based on W-CDMA in 2001. DoCoMo also offers a wide variety of leading-edge mobile multimedia services, including i-mode™, the world's most popular mobile e-mail/Internet service, used by more than 47 million people. With the addition of credit-card and other e-wallet functions, DoCoMo mobile phones have become highly versatile tools for daily life. NTT DoCoMo is listed on the Tokyo (9437), London (NDCM) and New York (DCM) stock exchanges. For more, visit www.nttdocomo.com.

i-mode and FOMA are trademarks or registered trademarks of NTT DoCoMo, Inc. in Japan and other countries.
NTT DoCoMo's FOMA service is only available to subscribers in Japan.