Inexpensive Satellite Does the Job

Chuck Murcko chuck@topsail.org
Fri, 25 Jan 2002 16:46:50 -0500


On Friday, January 25, 2002, at 02:41 PM, Eugene Leitl wrote:

> On Fri, 25 Jan 2002, Dave Long wrote:
>
>> Redundant Array of Communicating
>> Kilobuck Satellites?
>
> You'll need a cloud of them. A cloud dense enough for 802.11b will be a
> definite space shrapnel hazard. Could put a few 100 MByte of flash FIFO
> inside, and route bursty during mutual flybys. Latency would suck, 
> though.

Yep, we're talking 4 minutes or so at best for horizon-to-horizon on 
flyby exchanges. Awesome for mail & news though.

>
> Given that you need a coordinate system, this seems to ask for digital
> pulse radio. You'd get a timing, a positioning service by mutual TOF
> triangulation and routing in one package, plus it is pretty white and 
> low
> on juice consumption.
>

Yeah. Or GPS for coordinates, doppler corrected, etc. It would be 
cheaper/easier to implement than a straight pulse radio system because 
of ubiquity, but not independent. And accurate enough. You'd always see 
enough GPS birds. Heck, you could put 4 diversity receivers and run 
pairs of antennas at opposite ends of the satellite and use software to 
run a 4x2 diversity system that was tumbleproof.

Chuck