[time-nuts] Timing Distribution in Mountainous Terrain

[Oz-in-DFW]

On 9/9/2010 2:03 PM, Ralph Smith wrote:
> 1e-11 only buys you 3000 seconds of drift before blowing the 30 ns budget.
> Without going to cesium we will most likely need some form of mutually
> visible synchronization. 
Is Cesium even enough?  The requirement looks like about 6 parts in
10e-14.  That's hydrogen maser territory isn't it? 

Given the application you could probably achieve this with fiber
back-haul that you continually range and jitter filter to achieve that
resolution.  Not gonna be off the shelf, though.  Your could probably
layer data transmission on top of this.

Why not just periodically release a metalized weather balloon as a
calibration target, or use one to lift a calibrated reflector in the
event of an outage?  Or pick a conventionally tracked target as a
calibration source?

-- 
mailto:oz at ozindfw.net    
Oz
POB 93167 
Southlake, TX 76092 (Near DFW Airport)