| Sci
Tech
When GPS meets GIS
| Like the Internet, basic infrastructure of the GPS is free
to use and a handful of Indian players are enabling a host
of applications including many that also harness another
frontline tool: GIS. Anand Parthasarathy examines the sce
nario at the cutting edge of two technologies.
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THERE IS an irony in this somewhere: for two of the
key technologies that have dramatically changed the world . One is
Internet and the other is GPS.
GPS the Global Positioning System a network of
satellites, approximately 20,000 km above the earth, which could
help obtain an accurate fix of any point on the globe.
Moving in six different orbital planes at an
inclination of 55 degrees, the satellites passed overhead twice a
day once every 11 hours and 28 minutes to be exact and at any
given time, at least four satellites were `visible'. . You needed
measurements from three different platforms to fix a point on the
earth's surface by triangulation. The fourth fix gave a measure of
height.
Once a tiny computer was programmed to make the
calculations, the process for the end user was simple: Switch on the
satellite receiver. And you got your position in latitude and
longitude, accurate to a few dozen metres.
During the last Gulf War a decade ago, when
American foot soldiers were stumbling through the sands of Iraq and
Saudi Arabia, GPS receivers stuck on their helmets were said to be
of great help in helping them reach their targets.
Since those days the system has been refined; and
while still nominally controlled by the US military establishment,
GPS has evolved into a pervasive `personal technology'. .
And a host of value-additions provided as paid
services have transformed the basic GPS system into a reliable
satellite-backed, data channel, vehicle navigation tool . Other
nations Russia (GLONASS), China (Beidou) and soon the European
Union (Galileo) have also put money into their own satellite-based
positioning systems, and the best of today's technology is capable
of giving stunning accuracies of 10 metres or less, albeit for
military applications.
Last month, a seminar organised by the Bangalore
branch of the Institution of Electrical Engineers (UK), provided a
useful platform where one could see the strides made by innovative
Indian players in bringing GPS technology to this country and more
interestingly in marrying it seamlessly with a complementary
technology: Geographic Information Systems (GIS).
In purely official terms, India has been very tardy
in exploiting GPS; no meaningful national programme of satellite
based location has yet taken off, not even for compelling
applications like disaster management or freight movement.
That has not deterred individual private and public
sector developers: and the IEE event helped focus on the work of a
handful of institutions which have already developed GPS-compatible
receivers and ancillary systems many for the military environment.
The GPS product range of Bharat Electronics
includes an indigenously developed 12-channel receiver; vehicle
position and status monitoring systems, including emergency voice
communication and a GIS `engine' in the `open' operating system
Linux, which enables real time display of information on hand held
computers and laptops.
While these are all geared for the standard GPS
frequencies, BE has also developed in parallel, a Mobile Satellite
Service (MSS) tailored for India's own INSAT satellite platforms.
However, the hand held versions of the MSS receivers can also double
as GPS terminals.
Aerospace Systems Pvt Ltd is a Bangalore based
agency that has developed a range of GPS receivers for the demanding
aerospace and military market, under the generic name GPSMarg.
Accord Software and Systems, a decade old Bangalore based company is
also into GPS receiver technology as is Fugro Geonics Pvt Ltd, a
joint venture of the Mumbai-based Geonics (India) and Fugro Group,
an international player in GPS marine and land mapping services.
All these companies have the expertise to build GPS
receivers for a variety of applications from small handhelds to car
navigation systems to large rail and road fleet movement control
systems.
The GPS-GIS umbilical
One of the reasons why GPS has failed to enthuse
the mass consumer market in India is lack of complementary software.
A car navigation system would add less than two per cent to the
price of a mid-range family vehicle in India today and customers
would be as willing to spend money on this as on a car CD player or
an air conditioner.
But what will the driver do with it? The navigator
will work only if the major metros and all the major roads and
highways have been digitally mapped and can be overlaid on the
position grid of the GPS system.
To do this, one needs large data bases built up by
exploiting a technology that lies at the confluence of computers and
cartography Geographic Information Systems (GIS). The second
Eicher City Map book brought out by Eicher Good Earth for Chennai
was released earlier this year. The first for Delhi was a
pioneering publication, achieved the hard and, mostly old fashioned,
way.
The second attempt had the benefit of some more
technology advances and the high quality GIS mapping solution was
provided by WTI Advanced Technology Ltd, a Chennai-based company in
which the Tatas are the major stake holders. WTI's President T.R.
Srinivasan, explained that the primary source was the National
Remote Sensing Agency's (NRSA) high resolution panchromatic
satellite data of 5.8 metres resolution. Other sources were Survey
of India maps and the Chennai Development Authority's zonal and
divisional maps.
WTI engineers took about 12 months to capture data
pertaining to roads, railway lines, water bodies etc and process
them to create map pages in the scale 1:10,000. Extensive field
verification then filled in details like houses, street names,
public buildings till they were finally incorporated into digital
maps at 1:12500 and 1:6250 cartographic standards.
The result was a publication that with over 120
pages of maps and an equal number of index sheets was a steal at Rs
200, and on par with internationally famed publications like `London
A to Z'.
Based in Bangalore, Spatial Data Private Ltd has
created a series of `Spinfo' products digital spatial data on
cities, towns and villages. Their products for Karnataka, Kerala,
Bangalore, Chennai etc, can be customized for clients who want to
search according to specific geographical or demographic criteria.
The National Informatics Centre (NIC) has been
instrumental in adding a new Web-enabled dimension to Indian GIS.
Its Chennai Centre has created a useful TamilNadu maps website with
interfaces to officials at district, taluk and municipal level.
A presentation at the IEE seminar by NIC's V. S.
Raghunathan, Technical Director, highlighted how such public tools
could lead to better governance.
However, L.R.A Narayan, formerly with the Survey of
India, feels the majority of maps available in India are only
1:50,000 with 20-metre contour intervals and unless we produce
more maps of a scale like 1:5000 to 1:10,000 they will not be useful
for microlevel planning.
But a beginning has been made; according to Dr
D.J.Pal of the Centre for Development of Advanced Computing (C-DAC),
techniques like Photogrammetry measuring objects from aerial
photography are stepping stones to 3-dimensional GIS that will prove
invaluable for urban planning, geological surveys and resource
mapping.
The field is wide open and armed with such
state-of-the-art tools India is well equipped to create a better
life on earth for its 1 billion citizens, by harnessing that eye in
the sky.
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