17:56 Sat 17 Oct 20 , Martin Herren via Libre Space Community wrote:
got an antenna newbie question.
Currently i got a 2x2 MIMO 4G antenna i use for my initial little S-Band tests. It got 2 orthogonal linear polarization on individual N connectors. (https://kroksw.com/shop/antennas-gsm-3g-4g-wifi/broadband-mimo-feed-kip9-17002700-dp-for-satellite-dish/)
For now i use only one output.
- Would it be possible to combine both outputs using a phasing line and a combiner with impedance matching to turn it into RHCP ?
Sure, you can use a quadrature ibrid:
And is not difficult to built one by yourself but maybe you need a good
substrate: FR4 has too much loss for this purpose, every tenth of dB of loss
became a tenth of dB increase of NF
- Does it depend on the internal build of the antenna or would that be possible for all 2x2 MIMO antennas ?
I suppose the antenna has two orthogonal dipole or similar so each got a
polarization and can be combined with 90deg phasing to obtain rhcp or lhcp
- If possible would it bring some benefits ?
If sat is not stabilized signal will not change with attitude using cp
- Or just better build a helix ?
I’ve no experience with the antenna you mention but for what it cost it could
be a good attempt; I’ve no experience with S-band sats, too…
73, Lapo IK5NAX