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Setting the Transmit Rate
The Transmit Rate field specifies the rate at which the radio in your PRISM WLAN Interface card
transmits and receives data. You can view the available rates by clicking the down arrow at the right
of the Transmit Rate field.
The transmit rate can be set to:
•
=
Fully Automatic
– your PRISM card chooses the highest available rate providing reliable
communications based on the capabilities of the Access Point or station with which it communicates
and on the received signal quality
•
=
Auto 1 or 2 Mb
– allows only 1 and 2 Mb/s operation
•
=
5.5 Mb
– allows only 5.5 Mb/s operation
•
=
11 Mb
– allows only 11Mb/s operation
To change the Transmit Rate, click the down arrow at the right of the field, highlight the rate you want
to set, and click the
Apply
button.
Under most conditions, you should choose
Fully Automatic
as the transmit rate. In general, fixed rates
are used only in test environments.
Enabling Power Save Mode
The IEEE 802.11 standard provides a Power Save Mode. In this mode your PRISM card listens for a
beacon (a periodic frame which defines the network type and attributes) and determines the beacon
interval. Between beacons the card puts itself to sleep, enabling power savings. At the time of the
expected beacon the card wakes itself up and receives the beacon. The received beacon contains
information about whether the Access Point or station has buffered frames for the card. If frames are
available the card requests those frames until no more frames are available. The card then goes back
to sleep until the next beacon.
For Access Points that support power save mode and for stations equipped with WLAN cards,
enabling this mode can significantly reduce power consumption, which is particularly important if the
host computer is operating on battery power. However, be aware that power save mode also results
in lowered transmission and reception speed on the wireless LAN.
