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Re: Time to throw your az-el rotors out?

On Thu, 2005-05-26 at 23:28 -0400, Luc Leblanc VE2DWE wrote:

> Interesting but the following will be the hard component to get 
> actually.
> "Signals from the four antennas are analyzed using a processing 
> technique that learns to improve its performance by constructively 
> combining scattered and reflected versions of the signal, and by 
> suppressing noise and interference."
> Dont discard your rotors too quickly!

Not really - before computers and DSP we dealt with it (multi-path) by
use of multiple receiver sites (diversity) and a voter.  For many years
I ran a multi-state coverage UHF repeater in North Georgia - we had one
area frequently traveled by the co-owner where the mobile multi-path
through the mountain valley area was almost unbearable until we added a
second receiver that covered the affected area and avoided the
multi-path signals and our system voted between the two - sure wish we
had had DSP power then.  

As far as "diversity" - even antennas a few feet apart will have
different nulls and multi-path characteristics on non-stationary


Don Woodward
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