Yes, EGNOS is live, free, reliable, and all of that. Coverage are limited to Europe (similarly WAAS is available in the US, and I think also Canada and Northern Mexico) and a similar system in Japan (don't remember name).
EGNOS require clear view of the sky in the same way that the GPS needs, meaning that it will give no aid when the receiver is indoor. EGNOS does not provide positions to the algorithm, it provides corrections of the GPS satelites in order to enhance the algorithm in the unti. This often results in 50% better accuracy (or something like that) than the raw GPS position. There are a few other services that does the same, with more coverage. Most common is IALA, also live, free and reliable. IALA corrections can be activated on some GPS receivers, specially those advertised as dGPS units. The coverage of IALA is focused on the coasts as it aims on the maritime industry. How much it enhances the accuracy depends on the distance to the station. There are a serie of commercial services as well, but they usually need special hardware and expencive licenses to utilize. From my work place we use Spotbeam and Inmarsat (supplied from Fugro, these are the same signal, sent via different satelites), HP/XP (also Fugro, but a different signal), Veripos (transmitted by Veripos), IALA (free), SBAS (common name for WAAS/EGNOS/all other related systems), GPS464/GPS465 (Corrections transmitted by UHF link, generally used by Petrobras, very short range). Where I live and do ground survey for OSM there are no SBAS coverage (neither EGNOS nor WAAS), but hope that a similar system will be opened also here. I would also like to upgrade my GPS unit to one that can take both IALA and SBAS corrections and handles maps. (Current unit have SBAS corrections, no IALA, and no maps:( ) On Sun, Feb 21, 2010 at 3:47 AM, John Smith <[email protected]> wrote: > On 21 February 2010 09:50, Martijn van Exel <[email protected]> wrote: >>> - Is anybody working on Indoor maps AND would like to talk to me about it. >>> I will do a paper for theWhereBusiness news letter on that. ( I know some >>> of the volunteers are working on it and it would be great to ask them how >>> they do it) > > http://lists.openstreetmap.org/pipermail/dev/2009-November/017814.html > > _______________________________________________ > talk mailing list > [email protected] > http://lists.openstreetmap.org/listinfo/talk > _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
