Comparison Test of Marska wlan-antennas
One antenna at a time is mounted to the same antenna mast conduit on the
roof of house. Circumstances are quite hard. The distance to the ISP station
is 750 metres but there is no direct sight to there. Between my antenna and
the ISP station there are lot of trees and houses - fortunately not higher
than two-layers. Additionaly there is a link mast of telephone company and
bridge pillars too. See photo
.
Antenna models under the Test
As a reference antenna I used the panel antenna included in Freedom-set which is sold here in Finland. The nominal antenna gain of the Freeedom antenna is 12 dBi.
#1A. Antenna 1 , reflector from aluminium pan 240 mm dia, sides cutted to 32 mm height. The ring is 64 mm from the base.
#1B. Antenna 1 , same as above, but sides of the pan has left to original 55 mm height. No ring is used.
#2B. Antenna 2 "improved" or coffe can 105 mm dia with extra bottom.
#2C. Antenna 2 "funnel", tube100 mm dia, funnel overall dia 170 mm.
#3. Helix-antenna
. 42 mm plastic tube 560 mm length. 1 mm enamelled wire, 14 turns,
ascending 38 mm. Impedance converter from printed circuit copper foil cutted
triangled. The flange 125 mm dia.
Reading the results
The Test was done with Orinoco "red" wlan-card using Orinoco Client Manager's function Advanced/Link Test. It shows received (This station) signal levels as well as signal levels received from ISP's station (Test partner).
Signal on the table means received signal strength in dBm units. Less negative level is the better
Noise means noise level in dBm units. More negative level is the better.
S/N means marginal between signal and noise. The more value the
better.
The results in rank order
Measured at 20.9.2001
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3 % 5,5 Mbps |
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30% 5,5Mbps |
Measuring tolerances about +- 1 dB.
20.09.2001 Martti Palomaki
