An Investigation of the Impact of Signal Strength on Wi-Fi Link ...
An Investigation of the Impact of Signal Strength on Wi-Fi Link ...
An Investigation of the Impact of Signal Strength on Wi-Fi Link ...
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The RSS <str<strong>on</strong>g>of</str<strong>on</strong>g> “WDS with AP mode” was close to phase 1 measurement results because<br />
<str<strong>on</strong>g>the</str<strong>on</strong>g> radio propagati<strong>on</strong> envir<strong>on</strong>ment did not change significantly. The average throughput<br />
(4.736 and 4.364 Mbps, refer tables D.1 and D.2) were lower than <str<strong>on</strong>g>the</str<strong>on</strong>g> preliminary<br />
measurement results (5.755 Mbps, refer table A.3) and phase 2 measurement results<br />
(5.61 Mbps, refer table 5.3). The reas<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> varying throughput results is that <str<strong>on</strong>g>the</str<strong>on</strong>g> RX<br />
positi<strong>on</strong> was changed during phase 3 measurements. Fur<str<strong>on</strong>g>the</str<strong>on</strong>g>rmore, when RX was<br />
located close to <str<strong>on</strong>g>the</str<strong>on</strong>g> AP, it had better throughput and RSS, for example, measurement<br />
points “N”: -42 dBm / 5.562 Mbps, and “E”: -45 dBm / 5.332 Mbps.<br />
The measurement results showed that RSS and locati<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> AP placement have<br />
influenced throughput and performance. For example, when RX was located at positi<strong>on</strong><br />
“I” and was associated with <str<strong>on</strong>g>the</str<strong>on</strong>g> AP (SSID: Wellingt<strong>on</strong>), <str<strong>on</strong>g>the</str<strong>on</strong>g> throughput was <strong>on</strong>ly 3.241<br />
Mbps with -72 dBm RSS (refer table D.1). When RX was located at positi<strong>on</strong> “I” and<br />
was associated with <str<strong>on</strong>g>the</str<strong>on</strong>g> AP (SSID: Auckland), we gained a throughput <str<strong>on</strong>g>of</str<strong>on</strong>g> 4.237 Mbps<br />
with -67 dBm RSS (refer table D.2). Therefore, <str<strong>on</strong>g>the</str<strong>on</strong>g> results revealed that radio<br />
propagati<strong>on</strong> envir<strong>on</strong>ment and lower RSS would cause lower throughput and <str<strong>on</strong>g>the</str<strong>on</strong>g> positi<strong>on</strong><br />
<str<strong>on</strong>g>of</str<strong>on</strong>g> AP had impact <strong>on</strong> both <str<strong>on</strong>g>the</str<strong>on</strong>g> throughput and RSS.<br />
When RX was located at positi<strong>on</strong> “I” and was associated with different APs, we<br />
obtained different RSSs (-72 and -67 dBm). When receiver sensitivity <str<strong>on</strong>g>of</str<strong>on</strong>g> WLAN<br />
adapter is -74 and -69 dBm, <str<strong>on</strong>g>the</str<strong>on</strong>g> data rates are 36 and 48 Mbps (refer table 5.1). Thus,<br />
<str<strong>on</strong>g>the</str<strong>on</strong>g> estimated throughputs are 7.2 and 9.6 Mbps (refer table 5.1). Since we c<strong>on</strong>figured<br />
<str<strong>on</strong>g>the</str<strong>on</strong>g> APs as “WDS with AP mode”, <str<strong>on</strong>g>the</str<strong>on</strong>g> throughputs were <strong>on</strong>ly half <str<strong>on</strong>g>of</str<strong>on</strong>g> normal “AP mode”<br />
throughput. The estimated throughputs <str<strong>on</strong>g>of</str<strong>on</strong>g> positi<strong>on</strong> “I” should be 3.6 and 4.8 Mbps. The<br />
measurement results (3.241 and 4.237 Mbps) were close to <str<strong>on</strong>g>the</str<strong>on</strong>g> estimated throughput.<br />
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