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FM Repeaters, time for new ideas ?



Hi All, 
IHere are some thoughts following the threads regarding problems with the
current FM 
modes. It seems to me that the problem with the current FM repeater mode can
be 
define as follows: 

         due to the capture effect of FM modulation, base stations overwhelm
QRP stations that have the proper link budget. 

Now, I think that by the end of this year, we will have at least 3 additional
flying FM repeaters. This will not necessarily solve the problem, since
base/mobile stations will still try to access the satellites simultaneously.
Therefore, it is probably time to try to figure out a technical solution. 

There are two solutions I can think about: 

1. a FM repeater could have two uplinks mixed into one downlink. One uplink
will be designated for mobile operators, and there other for base operators.
This could give both types of operators a chance. Of course, with mixed audio,
some human carrier detect will need to be made in order to negotiate for the
channel. But if operators adhere to the 

rules, it would give the "arrow antenna/handheld operators" an equal chance to
use the system. 

2. The second idea closely resembles the P3D LILA. A level detector could
allow only weaker stations forcing the big guns to go to the minimum required
power level. 

I actually think that a combo of both ideas 1 and two could work well. 
Uplink #1 will have no limit, all the big gun can fight it out on this one.
Uplink #2 can will have DELILA (doesn't stand for nothing - but similar to
LILA), which will only allow lower level signal through. Enabling the QRPers
to join in on the action. 

  
I would love to hear comments about the ideas. 
assi 4x1kx/kk7kx   



--------------------------------------------------------------
 Assi Friedman, Deputy Program Manager - ASUSat Program
 Tel: 480-844-1458 (home)
 Tel: 480-965-2474 (ASUsat lab)
 Fax: 480-965-0277 (ASUsat lab)
 Email: assib@asu.edu
 Home Page: http://www.public.asu.edu/~assib
 ASUSat Page: http://www.eas.asu.edu/~nasasg/asusat/asusat.html
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