Qualcomm and Teleepoch
Enter Into a 3G CDMA Subscriber Unit License Agreement, October
6, 2007
MTN chooses Cambridge Broadband
Networks for multi-service wireless network in Rwanda, October 6,
2007
Brazilian government to
publish 3G bidding rules soon, October 6, 2007
KTF 3G service suffers
from technical problems, October 6, 2007
Argentina’s Personal
lunches 3G service in Rosario, October 6, 2007
Russia has it's first 3G
network, October 6, 2007
AT&T could drop Alcatel-Lucent
as 3G mobile network supplier, October 6, 2007
Enea Extends License Agreement
with ZTE for 3G Handsets, October 2, 2007
LG to unveil premium handsets
in Brazil, October 2, 2007
KTF 3G subscribers doubled
in less than 3 months, October 2, 2007
3G policy in India will
be non-uniform, October 2, 2007
- previous news
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Fujitsu achieves breakthrough output with Gallium Nitride HEMT amplifier
December 9, 2003
Fujitsu Laboratories announced that it has developed a gallium nitride
(GaN) high electron mobility transistor (HEMT) amplifier which achieves
the world's highest power output of 174 watts at 63 volts, while demonstrating
unprecedented record drain efficiency of 40%, fulfilling W-CDMA system
requirements for base stations. This breakthrough represents a significant
step forward in making smaller and more energy efficient base stations
for 3G mobile networks, and overcomes the technical hurdle for output
needs exceeding 150 watts required for realistic application in 3G mobile
systems.
For the next generation of high-output amplifiers, high expectations
have been placed on amplifiers comprised of GaN-based HEMTs, attributable
to the unique material properties of GaN. GaN can accommodate operations
at high voltages, while at the same time achieving higher output and greater
output efficiency.
If high power outputs capable of simultaneously amplifying multiple channels
can be achieved while efficiently converting power into radio frequency
signals, base station power consumption can be significantly reduced,
enabling simplification of the cooling system which results in smaller
and more cost-efficient base stations.
Up until now, Fujitsu used its proprietary GaN HEMT technology in conjunction
with distortion compensation circuits, demonstrating that the technology
would be applicable to 3G mobile base-station amplifiers that operate
at high efficiency.
The most critical factor for moving toward realistic application of this
technology is the ability for high-efficiency amplification that conforms
to 3G mobile communication base station standards, such as W-CDMA specifications.
Fujitsu's GaN HEMT amplifier, when supplied with 60 or more volts of power,
satisfies the W-CDMA specification for adjacent channel leakage, while
also achieving the record-setting drain efficiency of 40%. Proven distortion
compensation at 60 volts or higher, achieved by Fujitsu, is the world's
first.
As demonstrated by these results, Fujitsu's new GaN HEMT amplifier delivers
high performance to transmission amplifiers for 3G mobile communication
base stations, contributing significantly to the development of base station
systems that are smaller and more cost and energy efficient. Moreover,
it clears the practical hurdle of generating power output in excess of
150 watts.
Fujitsu is currently researching mass-production techniques and accumulating
reliability data, and expects to have commercial products available within
one or two years.
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3G Motorola A920
