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Space
Applications
The deep space
channel is characterized by wide signal bandwidth and low signal power. The
noise environment is substantially Gaussian in nature. In this environment
channel capacity increases approximately linearly with SNR.
The Consultative
Committee for Space Data Systems (CCSDS) is an organization established by
the management of member space agencies to address data systems issues and
to formulate sound technical solutions to these issues. Synchronization and
channel coding issues are dealt with in CCSDS recommendation 131.0-B-1.
Broadband Wireless Access
WiMAX is one of
the most exciting wireless technologies of our day and
because of its ability to deliver on the full promise of
wireless broadband—namely freedom, mobility and access
everywhere to abundant broadband data—it has garnered
unprecedented backing by hundreds of companies around the
world. Efficient error control is a driving force behind the
rollout of WiMAX.
The
establishment of the 400 member-strong, globally-supported
WiMAX Forum, the ratification of the 802.16 standards, the
availability of spectrum, and the expectation and desire of
consumers for broadband anytime, anywhere has created
unstoppable market momentum. This has spawned the
development of a large WiMAX ecosystem that today is not
only positively impacting user acceptance and adoption, but
driving volumes and price reductions necessary to sustain
the momentum.
Today, WiMAX
ASICs with advanced functionality are available from leading
semiconductor companies, enabling system vendors to further
lower costs. Fixed WiMAX equipment based on the 802.16-2004
standard has been certified by the WiMAX Forum and is now
being deployed commercially around the world. Mobile WiMAX
equipment based on the 802.16e-2005 standard is appearing in
pre-certified configurations today in anticipation of the
mobile WiMAX certification process that will begin in
mid-2007.
Over the next
few years, mobile WiMAX-enabled end user devices will be
widely available as a growing number of major operators set
in motion their mobile WiMAX deployment strategies. In one
of the industry’s most promising recent developments,
Sprint, the largest WiMAX spectrum owner, has announced that
it will build WiMAX networks and expect to serve more than
100 million people with WiMAX services by the end 2008.
Next
Generation Cellular
3GPP (WCDMA)
The 3rd Generation
Partnership Project (3GPP) is a collaboration agreement established in
December 1998, bringing together a number of telecommunications
standards bodies which are known as “Organizational Partners”. The
current Organizational Partners are ARIB, CCSA, ETSI, ATIS, TTA, and TTC.
The original scope of 3GPP
was to produce globally applicable Technical Specifications and
Technical Reports for a 3rd Generation Mobile System based on evolved
GSM core networks and the radio access technologies that they support
(i.e., Universal Terrestrial Radio Access (UTRA) both Frequency Division
Duplex (FDD) and Time Division Duplex (TDD) modes). The scope was
subsequently amended to include the maintenance and development of the
Global System for Mobile communication (GSM) Technical Specifications
and Technical Reports including evolved radio access technologies (e.g.
General Packet Radio Service (GPRS) and Enhanced Data rates for GSM
Evolution (EDGE)). Multiplexing and
channel coding issues are dealt with in 3GPP
recommendations TS 25.212 and TS 25.222.
3GPP2 (CDMA2000)
3GPP2, a parallel "sister project" to 3GPP,
was born out of the International Telecommunication Union's (ITU)
International Mobile Telecommunications "IMT-2000" initiative, covering
high speed, broadband, and Internet Protocol (IP)-based mobile systems
featuring network-to-network interconnection, feature/service
transparency, global roaming and seamless services independent of
location. IMT-2000 is intended to bring high-quality mobile multimedia
telecommunications to a worldwide mass market by achieving the goals of
increasing the speed and ease of wireless communications, responding to
the problems faced by the increased demand to pass data via
telecommunications, and providing "anytime, anywhere" services
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