On 8 Apr 2006 10:28:28 -0700, "Ron J" wrote:

Hello, I have Balanis' Antenna Theory 3rd Edition. I read on page 31 at
the very last sentence that "Side lobe levels of -20 dB or smaller are
usually not desirable in most applications."

Why? On the same paragraph it states that "minor lobes represent
radiation in undesired directions, and they should be minimized." If a
side lobe is a minor lobe, then why is it undesirable to have side lobe
levels less than -20 dB? Thanks!

Another possible explanation is that if the main lobe is pointed in a
direction with low ambient noise (eg quiet sky), the last thing you
want to capture is significant power from hot earth (or other high
temperature sources) via minor lobes.

Owen
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