[Song Dog]

I was at the office and thought I would give the GPS (telenav) a try. I typed in my address and was off on my way. It was dead on all the way there, except: was 300 feet off at my house destination. Is that typical? In town it was right with the curves in the road and such.
Also, as a note I live in the country, would that be the cause of it being off that many feet?

OOPS, needs moved to GPS section. Sorry.

In Christ,

Song Dog

[FF2]

You still had a data connection in your remote area? In order to show location on maps, a data connection needs to continue.

Also, particularly in some rural areas, mapping data can be old or even inaccurate. Actually, for any location data can be off. 300 feet off is not that bad for an actual house location.

[holden]

Originally Posted by Song Dog

I was at the office and thought I would give the GPS (telenav) a try. I typed in my address and was off on my way. It was dead on all the way there, except: was 300 feet off at my house destination. Is that typical? In town it was right with the curves in the road and such.
Also, as a note I live in the country, would that be the cause of it being off that many feet?

OOPS, needs moved to GPS section. Sorry.

In Christ,

Song Dog

This is pretty typical with Telenav from what I have seen also. It will get you to the place but sometimes it is across the street and the flag is showing an incorrect location. I use it for work and have found this to be anoying at times. It has actually driven me to make U-Turns in the wrong direction and on the wrong side of the street to get to a location. I have compensated by knowing this as a possible behavior and when I am nearing my destination, I pay attention to the address and know which side of the street I need to look for.
H.

[JSanders]

Wirelessly posted (8310; The Juggernaut)

And sometimes it is the adreesing database the system uses. I know my personal home adress shows in the middle of our block, not on the end where I live. That is a result of the address system used for your area.

[CanuckBB]

It is typical of all GPS navigation program. Map data is always accurate becaus map makers have coordinates. Addresses are assigned in blocks, such as Street A between B and C has addresses 100-150. Map makers then approximate where a house is by essentially dividing the distance between C and B by the number of addresses. If all lots are not equal in width, errors occur.If the SatNav software can get me on the right street within 300 feet of my destination, I think I can do the rest.

[domenic72]

Wirelessly posted

Originally Posted by CanuckBB

It is typical of all GPS navigation program. Map data is always accurate becaus map makers have coordinates. Addresses are assigned in blocks, such as Street A between B and C has addresses 100-150. Map makers then approximate where a house is by essentially dividing the distance between C and B by the number of addresses. If all lots are not equal in width, errors occur.If the SatNav software can get me on the right street within 300 feet of my destination, I think I can do the rest.

U beat me to the punch!! Was just going to say that it's logically impossible to have every address mapped to the correct coordinates...especially in rural areas where lots sizes vary immensely. I'd be a little disappointed if the gps was off by 300 feet in an urban downtown area but for rural, 300 is better than I'd expect.

[fonejunkie]

Originally Posted by domenic72

Wirelessly posted



U beat me to the punch!! Was just going to say that it's logically impossible to have every address mapped to the correct coordinates...especially in rural areas where lots sizes vary immensely. I'd be a little disappointed if the gps was off by 300 feet in an urban downtown area but for rural, 300 is better than I'd expect.

There's also a huge difference between the GPS being off by 300 feet and the mapping software being off by 300 feet.

Typically, the GPS accuracy is within 3 meters, per the DOD specifications. If you are triangulating with cell towers, it's even less accurate - generally accurate within the distance from your location to the cell tower to which you are connected.

The mapping software, however, is also subject to accuracy issues, and often times, that alone accounts for the 300 foot discrepancy. On my first GPS, a Magellan, the original software was off by 40 feet e/w, but spot on n/s. I could be driving north or south on a major road and the GPS would show me 40 to the west of the road, but if I were driving east or west, it was dead on. A subsequent upgrade of the maps fixed it.

So the 300 foot leeway could easily be the software, OR the GPS or a combination. You could always verify your location using Google Maps, BB Maps, Windows Live Search in addition to NavTeq, etc. Check the location with various software tools to determine what is really going on. I'd say that if they are all off by about the same amount, the problem could be the GPS... but generally, I'm guessing the inaccuracies are due to the mapping software.