Re: IS THE GALILEO SYSTEM IN JEOPARDY?



John.Sprung@xxxxxxxxxxxxxxxx wrote:
On Feb 14, 12:44 am, Alan White <alan.les...@xxxxxxxxxxxxx> wrote:

Not so. The latitude for 'poorest' reception is in the mid-40s latitude.


Very interesting -- so there's good coverage in the high 80's? I
always thought that the orbits were inclined enough to leave holes at
the poles. The mid-40's would cover the largest part of the U.S.,
from Oregon to Maine.

Thanks --


-- J.S.


reception is not the issue but accuracy is. There is a hole in the constellation because the orbit inclination no matter where you live in the world. The position of the hole moves around but it is about the same size. At the equator it is manifested as two holes at north and south horizon but they are only 1/2 the size to the effect is the same. At the North or South pole the hole is directly overhead so vertical accuracy can be degraded by horizontal accuracy is good since you can see satellites in all directions. As you move south from the pole the hole moves north and at 40 degrees the hole prevents satellite reception from the north completely. This causes the distribution of satellites to be non symmetrical and thus the accuracy for latitude is a bit poorer. However it still meets specs.

Dale

--
_ _ Dale DePriest
/`) _ // http://users.cwnet.com/dalede
o/_/ (_(_X_(` For GPS and GPS/PDAs
.

Relevant Pages

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