IGS Ponders the Implications of a Multiple GNSS World

IGS Ponders the Implications of a Multiple GNSS World
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Jul 14, 2008
GPS World

What does the rise of European GNSS Galileo, along with other systems coming
online, such
as China's Beidou, mean for GNSS users? The International GNSS Service (IGS) is
considering that very question, and anybody interested in the future use of GNSS
for
observing for high-accuracy applications will want to review its white paper on
the subject.

The IGS is a voluntary federation of more than 200 worldwide agencies that pool
resources
and GPS and GLONASS data from a network of more than 350 permanent, continuously
operating, geodetic-quality GPS and GPS/GLONASS monitoring stations around the
globe. At
one time called the International GPS Service before the creation of GLONASS, it
intends
to follow its integration of GLONASS with the integration of Galileo data in the
near
future, as the system comes online.

It is that future that portends a lot of changes over the course of the next few
years,
particularly for hardware, the organization says. It has posted a white paper on
its web
site, Considerations for Future IGS Receivers, that looks at the implications of
the
multiple GNSS systems that users will have at their disposal in the years to
come.

"There are two reasons why it makes sense for the IGS to study GNSS receivers
that will be
integrated into its network in the coming years," said the paper's authors, Todd
Humphreys, Larry Young, and Thomas Pany, in its introduction. "The new GNSS
signals that
will come online over the next decade will render current IGS receivers
obsolete, so it is
prudent to examine receiver options going forward.

"Second, the push to improve the accuracy of IGS products beyond current limits
demands
greater accuracy in the models used to describe receiver measurements," the
authors said.
"As a result, the IGS must demand from vendors more transparency into receiver
firmware or
adoption of user-specified algorithms."

The body of the paper considers modernized GNSS signals and their benefits for
the IGS;
surveys the range of expected receiver capability; considers current and future
commercial
geodetic-quality receivers; considers software GNSS receivers as an alternative
to less
reconfigurable traditional receivers; and lays out the authors' recommendations
to the
IGS. This includes a suggested schedule for the evolution of minimum IGS
receiver
requirements, which might be met by either future commercial or possibly
non-commercial
options, according to the organization.

Interested readers can view and download the IGS paper here.

Editor's Note: Jim Ray of the National Oceanic and Atmospheric Administration
supplied GPS
World with the above information. Readers interested in this topic should look
for this
week's edition of the GPS World Survey and Construction newsletter; editor Eric
Gakstatter's column in this edition also addresses this topic, and will also be
available
online later this week here at GPS World.