Despite the good performance of GPS, there are more than a few GNSS vulnerabilities and threats. Categorisation into unintentional and intentional is sometimes done to aid understanding. Unintentional disruptions include natural phenomena such as high levels of ionospheric disturbance and solar flares, as well as man-made phenomena including system errors (satellite or signal), and unwanted radio frequency transmissions (TV, microwave communications, radar, …).

Replacing the horizontal datum of a country is a complicated and difficult project. The decision to embark on such a “revolutionary” move should only be taken after in-depth studies to identify compelling reasons for such replacement. Here, we comment on the article by Tahir et al. published in the September 2011 issue of Coordinates.

April 2012
6th International Satellite Navigation Forum, 17-18 April, 2012,
Moscow, Russia, https://mycoordinates.org/the-6thinternational-satellite-navigation-forum/;

Interexpo Geo-Siberia, 17-19 April, 2012,
Novosibirsk, Russia, http://itcsib.ru/event/4-INTEREKSPO_GEO-SIBIR;

In Spatially Enabled Government
‘Government’ remains the key
And not the ‘Spatial Information’.
As the ‘governments’ are expected to imbibe
The ethics, principles and purpose
Of governance

For the purposes of this paper, the vehicle was tele-operated from the nearby BS with the operator manoeuvring with the aid of three onboard video cameras and a display of the LiDAR data in realtime. Autonomous operation using the LiDAR data and was demonstrated in Whitty et al. (2010)(For videos, see our YouTube channel: www. youtube.com/UNSWMechatronics).

Obviously, before any datasets can be compared or combined, they must be brought together onto the same datum (Janssen, 2009). The practice of transforming from one datum to another is not diffi cult and the necessary parameters are available in many different software packages. However, with the increased number of datums comes an increased number of ways to transform between datums.

While for foreign users, services are providing IRS satellite data, establishment and upgradation of ground stations for IRS data reception and RS data contributions from Indian Space Research Organization (ISRO) for disaster agreements such as International Charter and Sentinel Asia.

As you are aware GPS meets most of the navigation requirements of users. However, to improve the performance and integrity of the GPS system and to meet civil aviation requirements, the basic GPS system is to be augmented by GEO satellite with corrections and confi dences.

The Spectra Precision business within Trimble had very rapidly assembled a portfolio of optical and GNSS surveying products. While Spectra Precision had in-house engineering, design and manufacturing capabilities on the optical side, the GNSS products had been sourced from a variety of external suppliers.

March 2012,
Munich Satellite Navigation Summmit 2011,
13 – 15 March, munich, Germany,
www.munich-satellite-navigation-summmit.org;