RDL-3000
FAMILY
USER MANUAL
70-00158-03-00
Proprietary Redline Communications © 2015
Page
96
of 254
April 17, 2015
field below to enter the maximum time (seconds) to remain connected when operating
below the threshold.
Re-scan Interval
: (Scan Threshold enabled) Enter the maximum time (seconds) to
remain connected when operating at a UBR below the threshold settings. The timer is
reset if the UBR recovers to a level equal or greater than the threshold. See Scan
Threshold Enable above.
Using the Scan Threshold Feature
After the RDL-3000 has established a wireless link, the sector controller monitors the
uplink and downlink burst rates. The Rescan Interval timer is started if either the uplink
or downlink burst rate drops below the minimum burst rate set in the Subscriber Link
Configuration. If the burst rate recovers to a level equal or higher than the threshold
before the timer expires, the Rescan Interval timer is stopped and the counter is reset.
Otherwise, if the burst rate remains below the threshold for the full Rescan Interval time,
the subscriber drops the link and the RDL-3000 starts a new frequency scan.
In this example, the subscriber requires 1 Mbps (3 Mbps peak) throughput. There are
ten pre-defined channels. Other relevant settings are described.
Subscriber Link Configuration
Max. DL Burst Rate:
54
Max. UL Burst Rate:
54
Min. DL Burst Rate:
36
Min. UL Burst Rate:
36
Threshold Timer Enable:
Re-scan Interval:
45
Fig. 56: Web - Scan Threshold: Threshold Timer Example
1.
The subscriber is connected to a sector controller and operating normally at 54 Mb/s.
2.
No action is taken when the UBR drops briefly and recovers (above threshold).
3.
The Rescan timer is started when the UBR drops below the 9 Mbps threshold value.
4.
When the UBR remains below 9 Mbps and the Re-scan Timer expires after 45
seconds, the subscriber drops the wireless connection and immediately starts a new
frequency scan. The timing will be approximately as follows:
Channel Scan Time + Max Time to Link-Up
20 s + 90 s = 110 s (typical)
5.
A new connection is established after scanning and joining the network.
For example, a subscriber is powered-on and there are 10 discrete channels in the
frequency ranges list. The established link experiences fading or the RF
becomes partially blocked:
Rescan Interval Time + Channel Scan Time + Max Time to Link-Up
45 s + 20 s + 90 s = 155 (typical)
