D-Link Air DWL-900AP User Manual page 18

Network Functions of the Access Point
(continued)
Data Transfer Rates
The actual rate at which data transmission occurs varies according to the
strength of the signal transmitting the data. Distance and environment can
effect the strength of the signal that can be transmitted and received. The
signal strength determines the type of modulation technique used to encode
data, which effects the volume of data (i.e. the number of bits) that can be
encoded in a given space of the carrier signal. The IEEE 802.11b standard
specifies that WLAN devices adapt the rate of transmission to use the best
rate achievable. Each wireless device first determines if conditions diminish
signal strength and then chooses one of four possible bit rates (1, 2, 5.5, or
11 Mbps) based on this learned information.
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