User's Manual

Chapter 4 - Operation and Administration
4.2.6.5.9.1
Option enables or disables the Adaptive Modulation
ed, the algorithm supports decrease/increase of
between the lowest possible level (Modulation
meter. If
possible level, the Adaptive
Modulation algorithm has no effect.
The default selection is Enable.
4.2.6.5.9.2 Modulation Messages
n Adaptive Modulation Messages sets the minimum
interval between two consecutive adaptive modulation messages, carrying
f received signals. The messages in the AU include SNR
information on all the SUs associated with it.
4.2.6.5.9.3
th a low SNR (below 13), the Adaptive
vel when
ay try to use
s too high, resulting in a relatively large number of
The default is Normal.
4.2.6.5.10 Concate s
data frames into a single
frame for transmission to the wireless link. This feature improves throughput and
con applicable, and a single waiting period
according to the contention window mechanism before transmission. When
acc before the concatenated frame is transmitted to the wireless
medium. Up to 8 data frames can be accumulated, to a maximum total size of
enation process is performed separately for each
Adaptive Modulation Option
The Adaptive Modulation
decision algorithm. When enabl
transmission’s modulation levels
Level 1) to the value configured for the Maximum Modulation Level para
the Maximum Modulation Level is set at the lowest
Minimum Interval Between Adaptive
The Minimum Interval Betwee
information on the SNR o
The available range is from 1 to 3600 seconds.
The default is 4 seconds.
Adaptive Modulation Decision Thresholds
Enables selection between Normal and High decision thresholds for the Adaptive
Modulation algorithm. In links wi
Modulation algorithm may not stabilize on the correct modulation le
using the standard decision thresholds. In this case the algorithm m
a modulation level that i
dropped frames. The “High” option solves this limitation and ensures good
performance also in links with a low SNR.
nation Parameter
The Concatenation mechanism enables bundling several
reduces the overhead in the wireless medium, by requiring only one CRC for each
catenated frame, one RTS/CTS cycle if
concatenation is enabled, data packets in the queue of the internal bridge can be
umulated
4032 bytes. In the AU, the concat
destination SU.
A frame is a candidate for bundling into a concatenated frame if all the following
conditions are met:
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