"Jerry Stuckle" wrote in message
...
On 1/22/2014 5:32 PM, Irv Finkleman wrote:
Q. Is there a relationship between the efficiency of an antenna and the
received signal strength?
Definitely. Antenna efficiency works both ways - a less efficient antenna
will affect both transmit and received signals.
Just pondering on the matter. Because I have to operate with
restricted space antennas, usually with low efficiency, I wonder how
much of a relationship exists between Efficiency and Received Signal
Strength?
Just as much as between efficiency and transmitted signal strength.
This leads to more questions such as how much do radials contribute
to efficiency?
That depends on a lot of factors such as number of radials, length, height
above ground and ground conductivity, for start. Each situation is
different. But generally, for antennas such as 1/4 wave verticals,
radials will help.
IF that isn't enough, how much do radials contribute to the bandwidth?
See above.
And...
And...
I'm never to old to learn, but I am old enough that a lot of mathematical
mumbo jumbo and Smith Charts tend to confound me!
Unfortunately, the only way to predict how an antenna is going to work
in a specific situation with any accuracy is with math and Smith Charts.
So you can use the "tried and true" method - put it up and see what
happens 
In this case the smith chart and antenna modling programs probably won't
work. In the small confins there are too many variables in the near field
of the antenna. Not that the program would not work, but it might take
years to measuer everything in the near field of the antenna.
Like you said , the tried and true method. Put something up and see how it
works.
Often people tend to overthink a simple problem or over think a problem
there is no easy solution for.
For now, it might be just as good and easy to tack a dipole up in the
cealing of the room even if it is bent at all kinds of angles.
---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com