[Talk-ca] GPS inaccuracy

[Tom Taylor]

Mostly the buildings were two stories only. A high-voltage transmission 
line runs behind them, the width of the buildings and more away, but 
maybe it had some effect.

On 18/11/2012 11:23 AM, Pierre Béland wrote:
> Tom
>
> You can try to repeat the experience with this same GPS and compare your results.
>
> I dont know if this is the case for your. In urban areas, the tall buildings are obstacles to Satellilte signal. This increases the inaccuracy of GPS measurement. If you are close to a tall building, you wont receive a good signal from that direction. Your position is calculated with a principle of triangulation. You
> need to receive the signal fo at least three satellites. And results are
>   far better with four.
>
>
>
> Pierre
>
...