For Liars and Loafers, Cellphones Offer an Alibi

[Thomas Shaddack]

On Sat, 26 Jun 2004, J.A. Terranson wrote:

> Yes, I suppose that the more technical amongst us could selctively jam
> only the one signal, however, cellular phones are mighty low power
> devices, and I would not hazard a guess as to whether it would be possible
> not to overpower the wanted signals on something like this.

Not that low power. (Though we maybe just disagree on the definition of
"low" here. But even then it's still pretty strong, when we compare a
several watts transmitter on a "cancer tower" half-mile away with a
transmitter of similar size, but couple hundreds miles away on the low
orbit. Which is largely compensated with the correlation methods used to
retrieve the GPS signal from under the noise floor, which is something
necessary to keep in mind when considering advanced jamming approaches;
mere output power comparisons don't have to be a reliable way when such
factors are in the game.)

> Even if this is doable, it is out of reach of Jane Citizen.

If a J. Random Hacker with the necessary capabilities is within her reach,
the countermeasure is available to her regardless of her own tech skills.

With continuing outsourcing, there should be enough out of work engineers
available who are sufficiently hungry to risk working for the underground
market.