http://www.ntia.doc.gov/ntiahome/fccfilings/2003/bplcomments_08132003.htm
How did they arrive at the conclusion that most receiving antenna systems
are vertically polarized in the 1.7 - 80 MHz region ? Would anyone like to
share their take on this ? Im mostly curious and at the same time somewhat
skeptical
4. Measurement Procedure
Ensure that the antenna's main beam has an unobstructed view of
the BPL source. Photograph the antenna's view of the BPL source. Transmit
the same, repeatable test signals over the network for each signal
measurement. At the first location, examine the BPL signal envelope to
confirm or discover the repetition interval. Record the envelope over one
period. Start the peak value measurement system. Start the average value
measurement system to run concurrently with the peak value system. Upon
completion, switch to the quasi-peak system and perform a stepped
measurement. When the measurement system finishes, turn off the BPL signal.
Run the three measurements again.
Proceed to the next location and repeat the measurements in the
above paragraph. Generally speaking, most receiving antennas of concern in
the 1.7 ? 80 MHz spectrum are vertically polarized so these polarizations
will be used. In a few locations, average power measurements will be made
using both polarizations, noting that horizontally polarized receiver
antennas are also used and propagation effects may depolarize the BPL
signals.
Stephanie R. Koles WX3K
wx3k at arrl dot net
http://www.qsl.net/wx3k
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