I recently decided to compare antenna radiation at differing
elevations with differing ground conductivities. I used EZNEC 2.0
software (obviously using real ground parameters [I'll let others
tell of any limitations]) and my transmit antenna array as the test
antenna (on its main lobe) and varied the the conductivity. The
results are as follows:
ELEVATION 2.0 mS 44 Ms 5000 mS
Degrees Poor My Salt
Cndctvty Cndctvty Water
2.5 -4.1dBi 5.2 dBi 10.6 dBi
6.6 2.1 8.5 10.89 5000 mS pk
10 3.9 9.0 10.8
15 5.4 9.33 10.0 44 mS pk
22 5.92 9.0 9.7 2 mS pk
30 5.4 8.0 8.7
40 3.9 6.1 6.7
50 1.4 3.4 3.9
60 -2.4 -0.4 0.1
The interesting thing was not the expected improved low angle
radiation with improving conductivity, but rather that the radiation
was better at the higher angles as well.
73, Bill K0HA
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