It is interesting to note, via direct computation,
that such an asymptotic maximum throughput is very close to that achievable in the case of
N=10 given in Figure 4.7. In fact, through Eq. (24), we can show that in the 2 Mbps data
rate case, the asymptotic throughput is 1.669 and 1.596 Mbps for the basic and RTS/CTS
Performance Study of IEEE 802.11 DCF and IEEE 802.11e EDCA 76
cases respectively, while it results in 6.210 (basic) and 4.763 (RTS/CTS) Mbps for the 11
Mbps data rate scenario respectively.
4.3.3 Saturation Throughput Analysis
Having derived the capacity limits of the IEEE 802.11 DCF, we now carry out an analysis
devised to understand how far from its performance limits DCF operates. Such an analysis
appears more complex: since each station accesses the channel according to Binary
Exponential Backoff rules, the space state required to thoroughly model each individual
station (e.g., the number of retransmission suffered by each station, and the backoff counter
value) rapidly diverges, even in the presence of a small number of competing stations.
However, let us focus on a specific station, hereafter referred to as ???tagged??? station.
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