WAAS - is it working yet

[arn.george]

My garmin 182c has been struggling to find the WAAS signal - having searched the net some sites say that Europe is enabled and some say it is still only available in the US. Is anyone reading it? I have recently cut and joined the cable and wondering whether this may have affected it - still reading other satellites strongly though.

Alex

[swginn]

Was reading WAAS today around Cape Clear & Fastnet Rock, at least I think I was anyway. Was on my friends Tornado, using a Lowrance Chartplotter and when we were returning to Baltimore the unit alarm went off saying "WAAS signal lost". I suppose this means that we had a WAAS signal all day, but lost it as we entered the Harbour.

[tim griffin]

WAAS is US for Europe its EGNOS check these sites for more info though some
may be out of date now
www.esa.int/export/esaSA/navigation.html
www.rssi.ru/SFCSIC/english.html
www.howstuffworks.com/gps.html
www.igeb.gov
www.joe.mehaffey.com
www.garmin.com/aboutGPS/waas.html

regards tim
www.griffmarineservices.co.uk

[marknj]

I've had a couple of fishing boats using it for about a month now with no probs reported, it seems very stable although i'm not sure if it's offically on yet.

Mark

[Rupert Bear]

I have been using it since last Oct. do lose the satellites now and again and I have been led to believe it is only sats numbered above 30 that are equipped.
When I do get it it is very accurate

[Garygee]

Likewise

Was out this weekend and had WAAS shown all day.

Have been using it for a few months now.
Cant say its their 100% of the time but whenever I have had my plotter on its been their.

Regards Gary

[tim griffin]

www.esa.int/export/esaSA/navigation.html
www.rssi.ru/SFCSIC/english.html
www.howstuffworks.com/gps.html
www.igeb.gov
www.joe.mehaffey.com
www.garmin.com/aboutGPS/waas.html

your set is WAAS enabled so it will show reading WAAS how ever it needs the ground stations to bring the level of accuracy down to 5 metres check out the sites above , Egnos is the EUROPEAN version of WAAS but not active, as yet
regards tim
www.griffmarineservices.co.uk

[Garygee]

While I dont dispute Tims posts I spent some time today playing with my plotter.

The way the plotter performs gives every indication that WAAS is active & being used.

On powerup the plotter shows "Searching for WAAS"

After a while it changes to show "Using WAAS" and the type of navigation shows "3D Differential"

Now this gives me evey indication that the plotter is using WAAS.

If this is not the case then Garmin wants their wrist slapping as the information is very misleading !!.

Either this or WAAS is working ?.

Can anyone at Garmin comment ?.

Regards Gary

[jwalker]

Some while ago, before waas was active, my garmin looked for it, it never found it (of course), but it continued to look. It worked normally throughout. I'd say, you are in business. Let us know what sort of accuracy you are managing to get.

[tim griffin]

Hi Garygee
my set is WAAS enabled ie can read WAAS and my set reads 3d
i point you in the direction of www.garmin.com/aboutGPS/waas.html
if you open it , it will explain that although WAAS enabled your set needs the ground stations(and the two geostationary sattelites orbiting the equator) to bring the level of accuracy down to 3 metres currently
only available in North America the EUROPEAN version EGNOS is not currently active how it works and i hope im not teaching granny to suck eggs
here and if i am apologise now, the sattelites orbit the earth sending signal
to a ground station that corrects the time signal abit like a diferential gps
this brings the accuracy down to 3 metres basically ground stations(25) over America a wide area augmented system receive the signal and correct it before re transmitting to the two geostationary sattelites before it goes to our GPS ,in europe we will get a european geostationary
navigation overlay system that is the same as the Americans
working on the ground stations sending corrected signals to our GPS
this i am told is not operational yet but is expected to come on line soon
2/3 years hope this explains it for you, but do check the sites they are excellent,
regards tim
www.griffmarineservices.co.uk

[Garygee]

Hi Tim

Yes I understand how GPS & WAAS works, which is not disimilar to the old differental GPS but without a second receiver.

I have done some digging with some of my contacts (I am a design engineer with a company that designs GPS, GSM & GPRS technology) and can report the following.

WAAS IS ACTIVE, but only as a test signal.

The signal is present but not sending data which can be used for navigation yet.

This means that GPS's will report the presence of WAAS but will not increase their accuracy yet !.

This is not reported much as at present WAAS adds nothing.

Hope this clears thing up.

Regards Gary

[arn.george]

So, if WAAS is present as a test signal - will garmin pick up egnos instead? or is a software update/ change to UK spec away from WAAS required.
Seems to be a lot of confusion - maybe just mine!

[tim griffin]

WAAS IS ACTIVE, but only as a test signal.

The signal is present but not sending data which can be used for navigation yet.

This means that GPS's will report the presence of WAAS but will not increase their accuracy yet !.

glad we both agree on that then, so when do your sources say EGNOS is coming on line , and good point raised do we need a software update.
regards tim
www.griffmarineservices.co.uk

[Mike B]

I'm not sure if this is correct or just chinese whispers but I vaguely remember hearing that having WAAS switched on but not receiving a signal can actual degrade the accuracy of the normal GPS signal. Hence if there is no signal it is better to run with it switched off.

Additionally something I know is correct is that WAAS will not work if your unit is in battery save mode (im guessing this only affects handheld units).

Cheers

Mike

[arn.george]

Not sure if one can actually "switch off" the WAAS on the garmin 182c. In which case if I am "receiving" WAAS it is more inaccurate than not!?!

[DGR]

My understanding is that with WAAS just putting out a carrier signal, it just means that the GPS thinks (or indicates) that it is more accurate, but is in fact no more accurate than if you had WAAS switched off. I don't see why it should be any less accurate than a standard (non WAAS) system.

Incidentally, I don't know this for a fact - but someone did try to explain it to me the other day - and it sounded reasonable.

Dylan...

[Garygee]

Hi folks

Well their I cant find out any actual dates but have the following !.

Initial tests of EGNOS was using a specially-equipped Inmarsat satellite.
Cant find out if this is what we are seeing or its the actual satalites.
I suspect the actual satalites by now.

The first test signal was on Friday 6 June 2003 and we should have a full system working very soon. The system was supposed to go live Spring 2004 with the operational readiness review in April 2004 . Assuming it conforms it should go live very soon after

If I get any actual go live dates I will post them.

Regards Gary

[arn.george]

Out this evening and still struggling to get a WAAS signal - test or not
I have cut and rejoined the antennae cable and hoping this is not responsible. Getting good reception of satellites otherwise.

[Erin]

Hmmmm. Not sure whether this is right or not, but have just been having a play with my GPS in the garden (GPSMap 76).

If I turn on WAAS enabled I suddenly get two new satelites appear in the sky (Nos. 33 & 44). Would I be right in saying these might be the Egnos sats? They dissapear again if I disable WAAS. Doesn't make the blindest bit of difference to the accuracy mind you. Didn't manage to lock onto them though!

Also, a few times last year I remember the sat strength bar showed a little 'D' symbol at the bottom and the display showed '3D Differential'. Might this have been the WAAS/Egnos actually working. I think accuracy went down to less 10' at the time.

[tim griffin]

EGNOS test signal comes on june 2004 they are now going to link it to Gallileo
test signal 2005 operational 2008
WAAS is for the benifit of the federal aviation authority so planes can fly/land
better knock on effect is maritime benifits for greater accuracy ie down to 3 metres but only if you are in America see www.rin.org.uk great site and info
on their for the tech heads
regards tim
www.griffmarineservices.co.uk