Articles in the Articles Category

Nov 2005 | Comments Off on Beginning of a cycle of innovation GLEN GIBBONS


A report on ION GNSS 2005, 13-16 September, Long Beach, USA


Recent …

Nov 2005 | Comments Off on “Information from Imagery”

Ian Dowman, President, ISPRS explains …

Nov 2005 | Comments Off on The casualty


October 8, 2005.
The earth quaked again. This time more than 70,000 …

Nov 2005 | Comments Off on Signal propagation through the troposphere


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 …

Nov 2005 | Comments Off on JAMFEST, A cost effective solution to GPS vulnerability testing

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.

Nov 2005 | Comments Off on MARK YOUR CALENDAR

November 2005


International Conference: “Earth Observation foaterr vegetation …

Nov 2005 | Comments Off on Indoor positioning in wireless

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.

Nov 2005 | Comments Off on Innovations 1983 and 1996

Tidal Modeling for GPS Positioning –

In …

Oct 2005 | Comments Off on Building relationships

11th Technology summit strengthens Indo-Canadian relationship. 21-22 September 2005 New Delhi

The 11th Technology Summit and …

Oct 2005 | Comments Off on Make maps quickly

Seven out of ten customers of surveys and mapping who talk to the suppliers (consulting fi rms of surveying agencies) demand their maps to be delivered `yesterday’(!) or indeed as early as possible. These customers are `decision-makers’ who have taken some months (if not years) to come to the demand level! Same is the situation in respect of the tenders in mapping discipline. All the risks and uncertainties are put on the door of the suppliers / contractors. One should realize that although the surveying and mapping process never costs more than 1 or 2 percent of total budget, the same is not true when it comes to the time taken for the mapping project. The fact is that many projects are delayed just because the survey data of right quality and proper map was not made available to the engineer / planner.