Dear Bryan, LF Group,
ERP is defined by the field strength at a point distant from the TX. Field
strength is a measure of how much signal is present at a particular point in
space. Of course, if you place a receiving antenna at that point, the signal
level at the antenna terminals will be reduced if its polarisation does not
correspond to that of the signal. But the field strength itself does not
depend on the receiving antenna, or indeed the presence of any antenna at
all.
In practice, to measure field strength, you usually have to use some kind of
calibrated antenna to convert the radio wave into an electrical signal, with
a known relationship between field strength and antenna output signal level.
It is up to you to ensure that any effect of mismatched polarisation (or
directional pattern, mismatch or any other kind of gain or loss)is taken
into account.
Cheers, Jim Moritz
73 de M0BMU
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of captbrian
Sent: 08 October 2006 20:01
To: [email protected]
Subject: Re: LF: Re: erp ierp VY1JA
Well I always thought there was a large loss depending on the extent to
which polarisation differed between emitter and recvr.?
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