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Radar Satellite Bounce : Link Budget assuming satellite with passive retro-reflecting antenna.
This page assumes a passive satellite with an antenna beam pointed at your earth station site. The satellite antenna is assumed to be designed to reflect some of the power received directly back into the same beam coverage. This might happen if the satellite dish antenna feed comprises a circular ring aperture or horn. Note no amplifier or frequency change at the satellite. Maybe some doppler frequency shift due to orbit movement.
Assumptions:
Earth station transmit and receive efficiency = 65%.
Effective area of satellite rx dish = 50% of physical size
Satellite tx dish efficiency = 50%
If you assume a reflection based on just a 'random shape' then there will be more or less omni-directional radiation from the satellite and far worse results. I will have to look into what 'radar cross section' means? I suggest adjusting the satellite size till the satellite antenna gain is 0 dBi, if you want.
This calculator is speculative only. Probably wrong somewhere ! Tell me if you have comment to make. Thanks.
It does not look too hopeful to me unless some high power radar is used.
For something more realistic try 0.442 GHz, 26m diameter antenna and transmit power 32000000 watts, bandwidth 100 Hz.
More about radar range calculations: http://www.waves.utoronto.ca/prof/svhum/ece422/notes/24-radar.pdf
If we can get C/N better than -27 dB C/N in 2500 Hz reference bandwidth WSPR will work.? How about dishes pointed at points in the sky where satellite regularly pass by. e.g. O3b satellites above the equator, constellations with many satellites in many orbit planes, in polar regions dishes aimed at 250km above the poles where many satellite pass frequently?
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