This station will access the channel according to the Binary Exponential Backoff
mechanism specified for DCF, and specifically, as described in Section 4.2, it will double
the range in which the Contention Window is chosen every time a collision is encountered.
Hence, the tagged station will access the channel with a ???frequency??? (measured in terms of
number of accesses per channel slot) which depends on the number of retransmissions
already suffered by the considered frame: a high frequency when the CW value is small, a
small frequency conversely. Each of the remaining competing stations will, in turn, be
characterized by complex exponential backoff rules and, thus, very different Contention
Window (CW) values, depending on the specific history of each access attempt (e.g., the
number of retransmissions suffered by the actual head-of-line MPDU). However, in
stationary conditions, we argue that it is reasonable to consider their ???aggregate???
contribution as being, statistically speaking, invariant, and specifically to consider their
effect as the result of individual stations accessing the channel via a suitable (i.e., to be
determined) but constant permission probability.
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