EGNOS/WAAS

[+madaxeman]

Hello

 

Does anyone have a definitive answer as to whether EGNOS is available for the UK ?

ie. is it worth activating the WAAS facility on my GPS to obtain greater accuracy.

 

I have googled this and cannot seem to find any accurate/recent information, not even on the EGNOS web site !!

 

Cheers

Madaxeman

[+Just Roger]

Yes EGNOS is definitely working. However, the satelites (33 & 39 from memory) are quite low in the sky to the south so the further south you are the more you are likely to get a fix. It doesnt do any harm to have it enabled that I have ever found so I would say '"Switch it on"

[+Stuey]

Hello

 

Does anyone have a definitive answer as to whether EGNOS is available for the UK ?

ie. is it worth activating the WAAS facility on my GPS to obtain greater accuracy.

 

I have googled this and cannot seem to find any accurate/recent information, not even on the EGNOS web site !!

 

Cheers

Madaxeman

 

It's called WAAS in the UK and it is available, depending on whether you can see the satelite(s) or not. If you've got it you might as well switch it on and see what results you get.

[+Just Roger]

 

It's called WAAS in the UK and it is available, depending on whether you can see the satelite(s) or not. If you've got it you might as well switch it on and see what results you get.

 

Wrong way round! WAAS is the USA version. Egnos (European Geostationary Navigation Orbiting** Satelite) is the European version which is available in the UK.

 

** This raises the interesting question of what other types of satelite are there? I guess they just needed a vowel for the acronym.

[+JeremyR]

I tend to cache around the N54° line and I normally find the satellite only comes in sight once I'm pretty high up compared to the surrounding landscape, have no obstructions on the horizon to the south and have lots of sky visible. That said, when it is working, the GPSr accuracy is excellent, even with my lil yellow it makes finding the right spot a breeze so it's definitely worth the battery hit.

[+Team Sieni]

http://www.esa.int/esaNA/SEMKMQWO4HD_egnos_0.html

 

"EGNOS is now fully deployed and in its pre-operational phase. The system will undergo certification for safety-of-life applications before becoming fully operational. "

 

ie it's running but not yet used for safety critical stuff.

 

If I have a nice open surrounings with a good view of the Southern horizon, I often get the little "D" (for differential) appearing on the satellite status bars on my Garmin, and the reported error drops significantly. Whether the co-ord values are any better (and whether they'd be any more useful to me if they were) I don't know.

[+Stuey]

 

It's called WAAS in the UK and it is available, depending on whether you can see the satelite(s) or not. If you've got it you might as well switch it on and see what results you get.

 

Wrong way round! WAAS is the USA version. Egnos (European Geostationary Navigation Orbiting** Satelite) is the European version which is available in the UK.

 

** This raises the interesting question of what other types of satelite are there? I guess they just needed a vowel for the acronym.

 

Apologies, it's been so long since I thought about it, I just started referring to it as the way my Garmin names it. Serves me right for trying to be helpful but it's the same thing at the end of the day to you or me anyway.

[+scottpa100]

Yeah - its on - but like others have said, unless you're pretty high up (hills, mountains) it has not seemed to make much difference to accuracy from my experience. To which end is why I've switched it off as when you're high up you get a good signal anyhow and WAAS enabled (but yes EGNOS where we are) just munches more battery power.

 

All feedback is copyright IMHO.

[+*mouse*]

Not sure if it makes my signal more accurate or not but I have it switched on and I seem to be more likely to have a row of little D's than not so the signal seems easy to pick up....

 

Interesting that it should be harder to pick up WAAS in the North or when there isn't a clear view to the south. The best signals I have every were in Orkney (N59) at sea level on a northern beach (cliffs at my back to the south) where I had 10 satellites and each one also had a 'D'. At the time I thought it was cool to have a D for every satellite. Now I realise that the chance of that happening up there must have been even smaller then I first thought!

[+SidAndBob]

The last time I had an EGNOS signal I noticed the GPSr's accuracy had dipped. Then it disappeared again for another few months.

[+madaxeman]

Hello All

 

Thanks for your help and advice

 

I thought I would just switch on WAAS and see what happened. It immediately locked on to several satellites (up to number 32).

 

After about five minutes my Etrex Vista C unit picked up satellites 33 and 39 (AOR-E(3F2) and IOR-W/F5) and shortly I had an accuracy of 2m - amazing !!

 

I live in Wakefield in the north of England.

[+The Blorenges]

It can take 20 minutes sometimes for the GPS to download the almanac from the EGNOS satellite - when done you'll get the D's in the display (Garmin). I've had the accuracy normally down to 6' or 7', the best being 5'.

 

Now for the sad people amongst you like me......

 

Basic EGNOS..... there are ground stations called RIMS (Ranging and Integrity Monitoring Stations) and a MCC (Master Control Centre). For our region the RIMS are Cork, Gatwick, Glasgow and the MCC at Goonhilly Downs - I can't find out if they are all operational but think they are. The RIMS basically check the accuracy of the GPS signals and via an uplink station send a signal to the EGNOS geostationary satellites which then re-broadcast it to your GPS where it is used to correct the normal GPS satellite signal and provide higher accuracy (the RIMS know where they are and don't move!!). The picture below shows the satellites we can normally pick up. AOR-W (Atlantic Ocean Region West is 35 on the GPS, Artemis is 37 and IOR (Indian Ocean Region) is 44. Artemis overlaps with Inmarsat IOR-W 39 (not shown on the map). There is world wide coverage but not everywhere has RIMS so therefore whilst you can pick up the EGNOS/WAAS signal it may not be being corrected.

[+Chaotica_UK]

Funnily enough Ive been talking to Mr TeamSP about WAAS all weekend. We both were quite surprised to have the little D's appearing, I had not seen any since I had been caching on top of the Mendips last year and Mr TeamSP hadnt seen any since his trip to Florida at Christmas. I suspect we have not been that observant, but we will from now onwards as accuracy halved.

Mark

[+Nick_Scots]

I have a Garmin Cammo Etrex, with WAAS enabled I get plenty of D sats, down to 4 or 5 m accuracy. Sciehallion summit I got 2m acuracy . I thought that was differential signals ? There is one in the forth estuary for shipping.

 

Nick

[+The Blorenges]

I have a Garmin Cammo Etrex, with WAAS enabled I get plenty of D sats, down to 4 or 5 m accuracy. Sciehallion summit I got 2m acuracy . I thought that was differential signals ? There is one in the forth estuary for shipping.

 

Nick

 

I think you'll find only commercial GPS receivers have a DGPS capability, the ones we use don't without an external beacon receiver. WAAS/EGNOS provide effectively the same function. DGPS uses ground stations broadcasting a signal at about 300Khz.

 

By the way, another Gallileo satellite is about to launch.. so the European GPS network may actually happen!!

 

Chris

Edited March 8, 2008 by The Blorenges

[+L8HNB]

By the way, another Gallileo satellite is about to launch.. so the European GPS network may actually happen!!

 

Chris

 

Yes, glad we didn't wait for it - we nearly did............

 

Henry

[+Nick_Scots]

I think you'll find only commercial GPS receivers have a DGPS capability, the ones we use don't without an external beacon receiver. WAAS/EGNOS provide effectively the same function. DGPS uses ground stations broadcasting a signal at about 300Khz.

Chris

 

Are you sure ?

 

http://www.nlb.org.uk/dgps/dgps.htm

 

I have been getting DGPS for nearly three years in scotland. Sometimes as many as 5 of them.

 

Schihallion summit was the best with my Garmin Etrex Cammo.

 

Nick

[+The Blorenges]

I think you'll find only commercial GPS receivers have a DGPS capability, the ones we use don't without an external beacon receiver. WAAS/EGNOS provide effectively the same function. DGPS uses ground stations broadcasting a signal at about 300Khz.

Chris

 

Are you sure ?

 

http://www.nlb.org.uk/dgps/dgps.htm

 

I have been getting DGPS for nearly three years in scotland. Sometimes as many as 5 of them.

 

Schihallion summit was the best with my Garmin Etrex Cammo.

 

Nick

 

From your link "The radiobeacon system uses the LF/MF band 283.5 - 315 kHz in Europe (285 - 325 kHz in other parts of the world). The Radio Regulations governing the use of this band allow for supplementary information to be transmitted - such as DGPS signals. A full description of the technical characteristics of the system can be found in ITU-R Recommendation M.823 (1996)."

 

This lowband (MF) signal needs a special receiver which connects to the GPS and provides the differential signal that way. I is desgined for mariners. The Garmin series (Etrex etc) cannot pick up this signal. What we get (I have an Etrex Vista C) is the signal directly from the EGNOS/WAAS satellites. This produces the D in the satellite display as each satellite signal is corrected from the EGNOS signal. The EGNOS signal is generated from ground stations too and then sent up to the EGNOS satellites.

Chris

[+Happy Humphrey]

I had constant Differential (EGNOS) satellite reception last Friday in the Forest of Bowland (Lancashire). The only hitch (and I don't know whether it was to do with EGNOS - probably not) is that I bagged the trig point (and cache) at Wolfshole Crag, and to check the position I left the GPSr on top of the column for a few minutes so that it could get an "average" waypoint. When I checked back home, the waypoint was about a quarter of a mile out (west of the trig point in some random bog). The track looked pretty accurate though, and I used the GPSr to find the cache (it was spot on). Very odd.

Edited March 13, 2008 by Happy Humphrey

[+currykev]

So is there a "bottom line" as to whether to have it on or off? I've notice lately that with the D's my gps is taking longer to settle at the cache area. ..or am I becoming even more impatient than usual!

[+kewfriend]

Now for the sad people amongst you like me......

 

Basic EGNOS..... there are ground stations called RIMS (Ranging and Integrity Monitoring Stations) and a MCC (Master Control Centre). For our region the RIMS are Cork, Gatwick, Glasgow and the MCC at Goonhilly Downs - I can't find out if they are all operational but think they are. The RIMS basically check the accuracy of the GPS signals and via an uplink station send a signal to the EGNOS geostationary satellites which then re-broadcast it to your GPS where it is used to correct the normal GPS satellite signal and provide higher accuracy (the RIMS know where they are and don't move!!). The picture below shows the satellites we can normally pick up. AOR-W (Atlantic Ocean Region West is 35 on the GPS, Artemis is 37 and IOR (Indian Ocean Region) is 44. Artemis overlaps with Inmarsat IOR-W 39 (not shown on the map). There is world wide coverage but not everywhere has RIMS so therefore whilst you can pick up the EGNOS/WAAS signal it may not be being corrected.

Wow - I just thought it was grey bald late-middle aged men that were geeks. I stand corrected.

[+rutson]

What ARE you trying to say about Lucilla?

Edited March 13, 2008 by rutson

[+The Blorenges]

size] Wow - I just thought it was grey bald late-middle aged men that were geeks. I stand corrected.

Hmmmmm. To be generous, you could remove the "bald" and "late".

 

Surely you're not implying that I could have written that stuff about EGGNOGS?

 

MrsB

[+sTeamTraen]

So is there a "bottom line" as to whether to have it on or off?

 

Ooo-errr!

[+rutson]

MrsB: Your eggnogs are legendary!

Nick: I've been struggling to resist a similar remark for the last hour or so!