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(meteorobs) radio meteor polarisation diversity
Hello
I'm currently chatting to a guy (real expert in radio stuff) about
radio meteor observations. He was interested in the different setups
and is helping me construct an analog/digitial converter.
In one email he brought up the issue of loss of sensitivity due the
probable change in polarization of the radio signal after reflection
not matching your antenna. He then speculated on the use of helical
antennas.
Anyway he then thought that the real difference could be investigated
as per the quotes below.
==========================================================================
One technique often used in meteor reception is to use two identical
receiver system, but with one connected to a horizontally polarised antenna,
and the other one connected to a vertically polarised antenna. This way the
difference in polarisation can be studied. It is known in the trade as
"polarisation diversity reception". It may be a useful technique for you to
consider, depending on what your actual experimental aims are.
Another way of doing polarisation diversity is to have just one receiver,
but have a coaxial relay that switches rapidly between the horizontal and
vertical antennas. In synchronism the output of the receiver is switched
between two channels of a recorder. This way you can cheaply measure the
polarisation difference of the signal from the meteor.
==========================================================================
Any comments??
thanks
Bruce
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