[time-nuts] LightSquared vs old GPS gear: Antennas?

[Hal Murray]

Is it possible/interesting to design an antenna that has a low-angle cutoff 
at 20 or 30 degrees?  That probably won't eliminate many satellites that are 
useful for timing receivers.

I'm interested in things like a Z3801A or a ThunderBolt.  I'm assuming it is 
not reasonable to replace the GPS unit.  Replacing the antenna might be 
reasonable, assuming it's cost is low enough.

That only helps in a donut shape area around the LightSquared antennas.  
Farther away it's not necessary.  Too close and either the antenna would be 
too high or the power would burn through the antenna anyway.

I live in flat ground.  I'm not sure where the nearest cell phone tower is.  
I don't know of any on the nearby hills to the west.  To the east, they are 
either low or far away.  (Maybe I just haven't noticed them yet.)

Another option would be a setup to null out an signal at a specific compass 
angle.

I realize this won't help the zillions of currently installed GPS navigation 
units.  They are mostly consumer gear with relatively short expected 
lifetimes so the FCC might do something like say "5 years from now..." which 
would be nasty for people like us using ancient gear.



-- 
These are my opinions, not necessarily my employer's.  I hate spam.