An Investigation of the Impact of Signal Strength on Wi-Fi Link ...

The average data size <strong>of</strong> web transaction application (80Kb) seems too small for
graphic-rich web sites. We assume that an appropriate data size is 256 Kb, which is
based on minimum downstream speed <strong>of</strong> Xtra wireless plan [97].
Capacity is <strong>the</strong> number <strong>of</strong> concurrent users who can access application through an AP.
Each web transaction consumes 256 Kbps bandwidth. The capacity is calculated below:
Capacity (number <strong>of</strong> concurrent users) = (Throughput Mbps ) / (256Kbps)
Table 5.5 shows <strong>the</strong> capacity <strong>of</strong> an AP at different positions. For example, when AP is
located at position “E-3M” and “N-3M”, it can <strong>of</strong>fer 28 and 29 users to access web
application concurrently.
AP Position
Average Throughput
(Mbps)
Capacity
(number <strong>of</strong> concurrent users)
A 6.348 25
G 6.780 26
H 5.890 23
F 5.619 22
E-3M 7.283 28
I 6.837 27
L 6.898 27
J 7.369 29
K 5.655 22
N-3M 7.430 29
R 7.062 28
Table 5.5: WLAN capacity with a signal AP for web application.
Table 5.6 shows <strong>the</strong> capacity <strong>of</strong> two APs scenario. For instance, when two APs were
located at “E-3M” and “N-3M”, in our case study <strong>the</strong> total 57 users can access
graphic-rich web sites concurrently. However, <strong>the</strong> number <strong>of</strong> permanent staff was
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