[Moon-net] Satellite Scatter

[Chris Bartram]

SV3AAF Petros wrote:

> BTW!   real big fun on 144mhz CW yesterday when i  tried to work  SM2CEW
> with reflection on the International space station  when it was passing
> over EU. Amazing big doppler and we came to  RO  received and R sent but
> not completed.

Ben SM6CKU and I, with a lot of heavy mainframe computing assistance from 
John, G(W)(M)4ANB, co-inventor of the so-called 'Maidenhead' locator system, 
and now N6something, played extensively with scattering from 'space junk' on 
432MHz in the 1978 - 79 era. That was in the era before PCs were cheaply 
available! Using his 8m dish Ben heard my 8yagi/kW ssb signal scattered by a 
COSMOS launcher in a decaying orbit, although we never completed a QSO, as 
the windows were very short, as Petros and Peter have discovered. The tests 
were reported in the 4-2-70 section of the RSGB's Radcom at the time.

I'd hoped to return to those experiments when I came back on the air, just 
under five years ago, but I haven't yet had time to do so. 

One of the reasons for the previous series of tests coming to an end was that 
our 'back door' source of orbital information closed. Such data is now much 
more freely available, and the computing could easily be done on a PDA! 

'Satellite scatter' is a viable dx mode on 144, 432, and maybe the higher 
frequency bands, particularly if you use a scatterer in a relatively low 
orbit, with a radar cross-section as big as the ISS! To use it effectively 
would require the adoption of suitable operating procedures.

My current EME activity is mainly on 10GHz. It seems a pity to leave the 
system unused for half of any month, and I've wondered if it would be 
possible to use one of the constellations of geostationary DBS satellites as 
a scatterer.  I can't find any information on the RCS of the satellites, 
which doesn't surprise me, but a few casual calculations based on educated 
guesses suggest that it's possibly a viable means of making QSOs by EME 
equipped 10GHz stations, particularly if the solar panel arrays are suitably 
aligned. 

Does anybody have any more information or even want to try?

Vy 73

Chris
GW4DGU