User's Manual

Menus and Parameters
“Don’t Care” or “Not Set Yet” only in factory. Once a value is configured, it is not
sible to reconfigure the unit to either “Don’t Care” or “Not Set Yet”.
default value depends on unit type. In SUs with integral antenna it is set to
(read only). The default value for AUs that are supplied with a detached
nna is in accordance with the antenna’s gain. In units supplied without an
pos
The
19
ante
4.2.6.2.9
be adapted
to the distances of SUs from the serving AU:
ts for a response message before retransmission
(acknowledge time delay) should take into account the round trip propagation
of the farthest SU. (The one-way propagation delay at 5 GHz is 3.3
etween SUs located
should also take
e
r
ual mode, this distance is configured
ce from each of the SUs it serves, determine which SU is located the
rthest and use the estimated distance of the farthest SU as the maximum
ce.
to
t
of the cell. In certain situations, the operator may decide to improve the overall
throughput by reducing the slot size below the value required for full fairness.
This means that when there is competition for bandwidth, the back-off algorithm
will give an advantage to SUs that are located closer to the AU.
The Cell Distance Parameters menu includes the following parameters:
antenna the default is typically “Not Set Yet”.
Cell Distance Parameters (AU only)
The higher the distance of an SU from the AU that is serving it, the higher the
time it takes for messages sent by one of them to reach the other. To ensure
appropriate services to all SUs regardless of their distance from the AU while
maintaining a high overall performance level, two parameters should
 The time that a unit wai
delay
microsecond/km.) The higher the distance from the AU of the farthest SU
served by it, the higher the acknowledge time delay for all units in the cell
should be.
 To ensure fairness in the contention back-off algorithm b
at different distances from the AU, the size of the time slot
into account the one-way propagation delay. The size of the time slot of all
units in the cell should be proportional to the distance from the AU of th
farthest SU served by it.
The distance from the AU of the farthest SU served by it can be determined eithe
manually or automatically. In man
manually. In automatic mode, the AU uses a special algorithm to estimate its
distan
fa
distan
It should be noted that if the size of the time slot used by all units is adapted
the distance of the farthest unit, then no unit will have an advantage when
competing for services. However, this reduces the overall achievable throughpu
Operation and Administration
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