Configuration
QB.11-R Installation and Management
Interface Parameters
72
•
Channel Bandwidth:
This field is used to change the bandwidth. Values are 5 MHz, 10 MHz, or 20 MHz (as
available), as well as 40 MHz when Turbo mode is enabled (US non-DFS only; 5054-R only). Change the channel
bandwidth of the unit that is remote to you first, and reboot the unit. Then change the channel bandwidth of the unit to
which you are directly connected.
NOTE:
The 5 MHz channel bandwidth is not available when the selected country is
UNITED STATES DFS
.
•
Antenna Gain
You can modify the sensitivity of the radio card when detecting radar signals in accordance with ETSI,
FCC, and IC Dynamic Frequency Selection (DFS) requirements. Given the radar detection threshold is fixed by ETSI,
the FCC, and IC and that a variety of antennas with different gains may be attached to the unit, you must adjust this
threshold to account for higher than expected antenna gains and avoid false radar detection events. This can result in
the units constantly changing frequency channels.
You can configure the threshold for radar detection at the radio card to compensate for increased external antenna
gains.
The Antenna Gain value ranges from 0 to 35. The default value is 0.
You must set it to 23 dBi for 5054-R units, or
17 dBi for 2454-R units
.
Configuring this parameter on the 4954-R has no effect.
•
Satellite Density:
The
Satellite Density
setting is a valuable feature for achieving maximum bandwidth in a wireless
network. It influences the receive sensitivity of the radio interface and improves operation in environments with a high
noise level. Reducing the sensitivity of the unit enables unwanted “noise” to be filtered out (it disappears under the
threshold).
You can configure the
Satellite Density
to be
Large
,
Medium
,
Small
,
Mini
, or
Micro
. The default value for this
setting is Large. The smaller settings are appropriate for high noise environments; a setting of
Large
would be for a
low noise environment.
A long distance link may have difficulty maintaining a connection with a small density setting because the wanted
signal can disappear under the threshold. Consider both noise level and distance between the peers in a link when
configuring this setting. The threshold should be chosen higher than the noise level, but sufficiently below the signal
level. A safe value is 10 dB below the present signal strength.
If the Signal-to-Noise Ratio (SNR) is not sufficient, you may need to set a lower data rate or use antennas with higher
gain to increase the margin between wanted and unwanted signals. In a point-to-multipoint configuration, the BSU
should have a density setting suitable for all of its registered SUs, especially the ones with the lowest signal levels
(longest links).
Take care when configuring a remote interface; check the available signal level first, using Remote Link Test.
WARNING: When the remote interface accidentally is set at too small a value and communication is lost, it
cannot be reconfigured remotely and a local action is required to bring the communication back.
Therefore, the best place to experiment with the level is at the unit that can be managed without
going through the link; if the link is lost, the setting can be adjusted to the correct level to bring
the link back.
Sensitivity threshold settings related to the density settings for the unit are:
5 MHz
10 MHz
20 MHz
40 MHz (Turbo Mode)
(US Only; 5054-R only)
1.5
3
6
12
2.25
4,5
9
18
3
6
12
24
4.5
9
18
36
6
12
24
48
9
18
36
72
12
24
48
96
13.5
27
54
108
