Wireless traces from Jan 24th 2006 at UPRM Mayaguez Puerto Rico.
We began this experiment at ~ 10:00. Tests 1 to 8 were performed from rooftop to rooftop of 2 close buildings, approx. 500' apart. The goal was essentially to get everyone familiar with the equipment and go over Linux commands, and make sure the equipment was working properly. We performed some iperf tests over this link with several different scenarios.
After lunch we performed tests 9 - 22 from rooftop to rooftop over a link approx. 1 mile. We made measurements using iperf, and recorded two sessions transferring some radar data.
Short Link ~ 500'
Trace 1: This was
our first test, with the default wireless settings. Link Quality was around
30/94. We performed iperf with default settings also.
Files: thinkpad/test1_tcp
dell/initial_default.cap
Trace 2: We
noticed approx. 20 other access points when doing a scan, so we decided to
switch to ch11. Signal strength improved to about 50/94, used default iperf commands.
Files: thinkpad/test2_ch11_tcp
dell/default_ch_11.cap
Trace 3: In this
test we performed an iperf test with UDP, signal
strength at 50/94. During the test we realized that we
lost the connection.
Files: thinkpad/test3_ch11_udp
dell/ch_11_udp.cap
Trace 4: We reset
the cards and ran the previous test again. This time it was successful, we
utilized almost all the bandwidth.
Files: thinkpad/test4_ch11_udp
dell/ch_11_udp_2nd_try.cap
Trace 5: For this
test, we set the distance for the wireless drivers with the athctrl
utility to 1 meter. We ran iperf with UDP. We
realized that the utility had not been run on both sides of the link. Signal
strength was around 54/94
Files: thinkpad/test5_ch11_udp
dell/udp_1_meter.cap
Trace 6: Here we
corrected for the issue in trace 5, both sides of the link now had the distance
for the drivers set to 1 meter. Signal strength was around 54/94
Files: thinkpad/test6_ch11_udp_1meter
dell/udp_1_meter_both_sides.cap
Trace 7: We ran
the previous test, with the drivers for both cards set to 1 meter, and ran iperf with TCP. Signal strength was around 54/94
Files: thinkpad/test7_ch11_tcp_1meter
dell/tcp_1_meter_both_sides.cap
Trace 8: In this
trace we tested the strength of the signal of the side lobes by turning the
antennas 90 degrees in one direction, and then 90 degrees in the other
direction. Our signal strength at 90 degrees was around 39/94 and the direct
signal strength averaged 55/94.
Files: thinkpad/test8_ch11_tcp_1meter_side
dell/tcp_1_meter_side_lobe.cap
Long distance link
~ 1 mile
Trace 9: <bad
capture> - we had trouble with this one (no connection/signal faded). There
is no corresponding trace on the dell. We had some setup issues when trying to
get the long distance link up.
Files: thinkpad/longtest9_tcp_2000m
Trace 10: This
was our first test after making a connection on the long distance link. We set
the drivers of both wireless cards to 2,000 meters using the athctrl utility. Signal strength was around 30/94. We ran iperf with TCP.
Files: thinkpad/longtest10_tcp_2000m
dell/longdistance/first_test.cap
Trace 11: We
tested setting the distance higher, this time we set it to 5000 meters
over-shooting the distance to see what would happened. Signal strength dropped
slightly. We ran iperf with TCP
Files: thinkpad/longtest11_tcp_5000m
dell/longdistance/tcp_5000.cap
Trace 12: Now we
adjusted the distance to 1600 meters, which was more accurate. We ran iperf with TCP
Files: thinkpad/longtest12_tcp_1600m
dell/longdistance/tcp_1600.cap
Trace 13: We
tested setting the distance at various intervals, here it was set to 1000
meters and we ran iperf with TCP.
Files: thinkpad/longtest13_tcp_1000m
dell/longdistance/tcp_1000.cap
Trace 14: In this
test the distance was set to 1000 meters and we ran iperf
with TCP.
Files: thinkpad/longtest13_tcp_500m
dell/longdistance/tcp_500.cap
Trace 15: For
this test we set the distance back to 1600 meters, where we had seen the best
performance. This time we transferred 40MB of data with iperf
using TCP. Signal strength was approx. 39/94
Files: thinkpad/longtest14_tcp_1600m_40MB
dell/longdistance/tcp_40m_1600.cap
Trace 16: For
this test, we used the same distance, 1600 meters and with 40MB of data, using
UDP. There were some issues on the Dell side which required a reboot.
Files: thinkpad/longtest15_udp_1600m
dell/longdistance/udp_1600_2.cap
Trace 17: We ran
the previous test (16) over again.
Files: thinkpad/longtest16_udp_1600m
dell/longdistance/udp_1600_3.cap
Trace 18: <bad
capture> something went wrong and not enough data was captured in the trace.
Files: thinkpad/longtest17_udp_1600m
dell/longdistance/udp_1600_chan_11.cap
Trace 19: <bad
capture> something went wrong and not enough data was captured in the trace.
Files: thinkpad/longtest19_udp_800m_ch11
dell/longdistance/afterreboot/udp_800.cap
Trace 20: <bad
capture> something went wrong and not enough data was captured in the trace.
Files: thinkpad/longtest20_udp_1600m_ch11
Trace 21: We transferred
a large file consisting of radar data using ftp over the link. Signal strength
was about 39/94 and we had both cards set to a distance of 1600 meters.
Files: thinkpad/longtest21_radardata_1600m_ch11
dell/longdistance/ftp_xfr.cap
Trace 22: In this
test we transferred 1GB of radar data via ftp with the drivers set to a
distance of 1600 meters. There was an issue on the Dell side which resulted in
no capture, but we have data from the ThinkPad side.
Files: thinkpad/longtest22_1GB_radardata_1600m_ch11