[time-nuts] GPS from a window seat

[Lux, Jim (337C)]

On 10/4/09 1:06 PM, "Bill Hawkins" <bill at iaxs.net> wrote:

> Group,
> 
> As to interference with other GPS receivers, my son runs a deep-sea fishing
> party
> boat out of Ocean City, MD. He is famous for knowing where the fish will be.
> There
> may be 5 to 20 people on a 50' fiberglass boat using GPS units to log his
> fishing
> spots. He'd be delighted if those receivers interfered with each other. He
> sees no
> interference with his GPS navigation system.


Interesting.. He's got an incentive to figure a way to prevent all those
folks from knowing precisely where he is, while he still needs GPS to
navigate there, so a simple short range jammer (leaving aside the legal
issues about jamming in general) wouldn't serve.

A GPS signal simulator with a bogus (but close) location would be useful,
and might actually fly under the Part 15 rules. The radiated power would be
very low (a few mW) so it probably would fit in the "not interfere" rules,
in general (e.g. You can radiate on your own property, e.g. In an anechoic
chamber for testing, it's only if you interfere with someone outside your
"boundary" that it gets sticky).