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Not by technology alone ARVIND SIVARAMAKRISHNAN
GPS surveyed time-invariant sea floor depths for safe navigation MUNEENDRA KUMAR AND GEORGE A MAUL
Reconfigurable software GNSS receiver in multipath environment FABIO DOVIS, MASSIMILIANO SPELAT, PAULO MULASSANO, MARCO PINI
Indoor positioning in wireless LAN JAYWON CHEY, JANG GYU LEE, GYU-IN JEE
JAMFEST, A cost effective solution to GPS vulnerability testing LT COL ERIC LAGIER, CAPT DESIREE CRAIG, PAUL BENSHOOF
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Space environmental effects on satellite communication can be considered as related to space segment, ground segment and on the signals propagating through the earth’s lower and upper atmosphere. The atmospheric structure has significant influence on signal propagation. This has definite influence on the data processing methodologies. The specific applications with which are concerned here are …
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All roads lead to GIS…
…The Rural Road Development Project
The Rural Road Development Project, Pradhan Mantri Gram Sadak Yojna (PMGSY) is using GIS for planning and decision making. An Online management tool OMMAS is being developed to populate the attribute data for GIS and provide access to the citizens to view status of various rural roads and other related information. Public Works Department Rajasthan is playing leading role in creating GIS data base and implementing the PMGSY Scheme. A customized standalone GIS software GRIMMS to run various queries related with planning of roads is being developed. Web GIS module is also being developed to make the complete system transparent and will allow citizens to access the information in spatial format related with PMGSY. C-DAC Pune is providing the technical assistance. Submitted by K.K.Mishra, mishra09720@itc.nl
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OS seeks partners for GPS correction service
Ordnance Survey is offering Licensed Partners and other interested parties the chance to develop positioning services based on a revolutionary national framework for correcting signals from orbiting satellites. OS Net is a network of more than 80 GPS base stations designed to enable different levels of improved real-time accuracy from the Global Positioning System (GPS) anywhere in Great Britain. OS Net is already delivering efficiencies for Ordnance Survey field staff where it is enabling centimetre-level positioning for their data-collection operations. Now, Ordnance Survey is planning to make the service publicly available through a tier of partner organisations. www.ordnancesurvey.co.uk/business/technical/osnet.html
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The 746th Test Squadron (746 TS) has conducted complex GPS jamming experiments since the early 1990s and played a key role “behind the scenes” creating multiple high-profile jamming environments for programs such as the Joint GPS Combat Effectiveness (JGPSCE) exercises and Quick Reaction Tests. These programs, conducted to support real-world operations, enhanced the 746th TS’s ability to recreate realistic jamming environments and resulted in the 746 TS earning the reputation as the recognized experts for open-air GPS vulnerability testing.
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Applanix launches the DSS 322
Applanix has announced the launch of its next generation Digital Sensor System, the DSS 322. The new system incorporates a 22 megapixel CCD array, Aerolens™ custom-manufactured optics, and TruSpectrum ™ technology engineered to maximize the system’s capability in generating high-quality color and CIR (color infrared ) digital geospatial imaging products. Applanix has also announced the release of its new POSTrack system designed for streamlined airborne direct georeferencing and in-flight task automation. The new system combines the latest integrated Inertial/GPS technology from Applanix with the Flight Management System (FMS) expertise of Track’air B.V. in The Netherlands.
airborne@applanix.com
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Recently mobile location based services (LBS) are provided via a mobile terminal such as a personal digital assistant (PDA), a cellular phone and so on. The location method that searches where the mobile terminal of a user is accurately is a key factor for providing convenient and useful LBS. The most well known method associated with positioning system is GPS. The signal of GPS satellites can be always acquired outdoors and this system provides comparatively accurate location information. However, there are difficulties in applying GPS directly to indoor positioning because of the weakness of signal. And the positioning using the mobile communication signal between a base station and a cellular phone does not provide adequate accuracy due to some technical limitations of communication systems when applied to navigation. In addition, severe multipaths are present in an indoor environment. So a new wireless communication technology is required for indoor positioning to achieve a better and appropriate accuracy. Wireless local area network (LAN) has been installed in a number of indoor areas such as office, terminal, campus, and park with interests in mobile Internet. Therefore, it is expected that a wireless LAN signal would be easily acquired for indoor positioning. Various positioning measurements like time of arrival (TOA), time difference of arrival (TDOA), and received signal strength may be employed for indoor positioning. Employing TOA or TDOA measurements requires a time synchronization between a transmitter and a receiver. But, a time synchronization between a transmitter and a receiver is very difficult if not impossible in a wireless LAN. Therefore, it is more appropriate to use signal strength for indoor positioning with a wireless LAN.