User's Manual

Chapter 4 - Operation and Administration
CAUTION
A value o y be used in point-to-f 0 disables the contention window back-off algorithm. It should onl
point app lications. For more details on configuring units in a point-to-point link refer to section
4.2.6.2.10.
4.2.6.5.3 Maximum Contention Win
ximum Contention Window parameter defines the upper limit for the
ber C used in the b ff algorithm as described in Minimum
Contention Window above.
The available values are 7, 15, 31, 63, 127, 255, 511 and 1023.
The default value is 1023.
4.2.6.5.4 Multicast Modulation Level (AU only)
The Multicast Modulation Level parameter defines the modulation level used for
multicast and broadcast data frames. Multicast and broadcast
s are not acknowledg ; therefore if a multicast or broadcast
rly received there is no possibility of retransmitting. It is
recommended that you set a lower modulation level for broadcast and multicast
bability that they are received without
errors.
4.2.6.5.5
e Modulation Algorithm (see section 4.2.6.5.9
dow
The Ma
maximum num ack-o
transmitting
transmission
transmission is not prope
ed
frame transmissions to increase the pro
The Multicast Modulation Level parameter is applicable only to data frames.
Beacons and other wireless management and control frames are always
transmitted at the lowest modulation level, modulation level 1.
The range is from 1 to 8.
The default is 1 (the lowest modulation level).
Maximum Modulation Level
When the Adaptiv ) is enabled, it
ynamically according to link conditions. The
ability of using the maximum possible modulation
der
conditions, a higher Maximum Modulation Level increases the number or
is being reduced by the Adaptive
high number of retransmissions reduces the overall
throughput of the applicable SU as well as all other SUs associated with the same
AU.
changes the modulation level d
purpose is to increase the prob
level at any given moment. Although the algorithm will avoid using modulation
levels that are too high for the prevailing link conditions, it might be better un
certain conditions to limit the use of higher modulation levels. If the link quality
is not sufficient, it is recommended that the maximum modulation level be
decreased, as higher modulation levels increase the error rate. In such
retransmissions before the modulation level
Modulation Algorithm. A
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