Japanese NTT DoCoMo, Inc. unveiled today three prototype high-speed downlink packet access (HSDPA) handsets developed with Fujitsu, Motorola and NEC, respectively, promising high volume downloadings at tremendous speeds.

HSDPA, also called 3.5G, is a high-speed packet transmission technology theoretically achieves a maximum downlink speed of about 10Mbps. Presently, the prototype handsets have maximum speeds of 3.6Mbps, 10 times faster than current 3G FOMA handsets. Launched 2001, the FOMA technology was the world's first 3G mobile service based on W-CDMA.

NTT DoCoMo expects that the HSDPA will facilitate powerful new services by enabling high-volume downloads and the viewing of highly rich content.

However, the success of this technology as a GSM-replacement, vis-?-vis other contenders like CDMA2000 or 1xEV-DO not yet finished cellular datacommunication standards like WiMax (IEEE 802.16) is still unclear. KDDI's CDMA2000 is generally considered as being much more successful and smooth than DoCoMo's and Vodafone's UMTS / W-CDMA introduction in Japan, which are much slower than initially hoped.

The handsets will be demonstrated at the DoCoMo booth at the 3GSM World Congress 2006 in Barcelona, Spain from February 13 to 16.

DoCoMo aims to start HSDPA services sometime between July and September 2006.