Rob Saecker wrote:


> The amount of fuzz is varied continuously, but the U.S. military knows what
> it is and can therefore correct for it for their uses.

Close. The extra bits are encrypted, and domestic units aren't
equipped with the key.

However, some - perhaps higher-end, non portables? - triangulate
between several satellite readings, and compute a more accurate
position.

--
- Don Baccus, Portland OR <donb at rational.com>
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