Number Of Satellites You Usually Track?

[+g0t0pless]

On average, how many satellites does your GPS usually track?

 

I am asking this because I often see people saying "I can only track 1 or 2" or "I couldn't find the cache because I could only see 2 stellites".

 

My GPS very rarely ever drops below 5 satellites, and is almost always tracking 7 or 8. And that is even in thick wooded areas.

 

I do realize there are differences in make and model of the GPS, and even differences in geographical area of the country or world.

 

I'm just curious how many satellites you end up picking up on your normal cache run.

Edited September 19, 2005 by g0t0pless

[+geoduck.5]

For any GPSr, you need to have no less than 3 satellites to give your position. Its called

trilateration. For a good schematic of this look at this website: How GPS works

 

The more satellites you have locked on your reciever, the more accurate your position will be.

[+g0t0pless]

Yes, I know how they work. I was wondering how many most people are able to track when they are out and about.

 

That site was a good read though.

[+wolfmaster]

On a clear day in the open I have seen seven or eight on mine. Under the canopy in the bush, I'm happy to keep three

[+briansnat]

Varies widely. Under heavy tree cover I will usually see 3-5. In the open could be 7,8 or 9 ( I never actually counted but I see a lot of bars) .

[+gpsblake]

I don't know if this is true but I read somewhere that while you are tracking 7 or 8 satellites, your GPS only uses 4 of them at one time. The 3 strongest for a lat/long fix and then the 4th strongest for the elevation. Please correct me if I am wrong. The GPS will constantly change which 4 they use based on signal strength.

Edited September 20, 2005 by gpsblake

[+g0t0pless]

It also grabs the time and uses them for "corrections" since signals can bounce off of objects, creating a longer path, and therefore incorrect readings.

[+TeamRJJO]

I don't know if this is true but I read somewhere that while you are tracking 7 or 8 satellites, your GPS only uses 4 of them at one time. The 3 strongest for a lat/long fix and then the 4th strongest for the elevation. Please correct me if I am wrong. The GPS will constantly change which 4 they use based on signal strength.

Three satellites are need to generate a position, the fourth is needed to resolve receiver clock bias.

 

Peace,

TeamRJJO

[+reveritt]

Usually 4 to 8.