Re:WHY?!?!?!?! (Score 2)

The reason for this is that the American military use something called spoofing. There are two type of GPS transmission as far as I can remember from University : S-CODE and P-CODE. When the US or Nato is involved in a conflict, the spoofing is turned off, allowing accuracies down to about 30cms (I think 1cm is a fallacy). You can always get around the spoofing using something called fast-static GPS. The reason the military code cannot be easily cracked or jammed is because it is only repeated approx once a month, whereas the civilian frequencies are repeated frequently. This is all from memory of my studies over 3 years ago, so don't flame me if im wrong!
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