Adaptive Rest Channel Rotation
Adaptive Rest Channel Rotation (ARCR) is a repeater feature that was introduced in R2.4. It is used on Capacity Plus (Single Site and Multi Site) to provide resiliency when there is a problem with the current rest channel host repeater. It works by determining whether there is a sudden drop in inbound call requests pointing to a potential problem with the frequency or hardware.
Operation
Essentially, ARCR forces a rest channel to automatically move to another repeater if there are no incoming calls on the rest channel for a specific duration. The duration is adaptively changed, based on the volume of incoming calls. To ensure a guaranteed rest channel rotation in all call volume conditions, the duration is limited between:
- A minimum of the subscriber inactivity time (SIT) plus one beacon duration
- and the maximum time which is equal to the CPS/RM Rest Channel TOT value.
For proper operation, the Rest Channel TOT value must be same on all the repeaters of a site.
If so desired, ARCR functionality can also be completely disabled by setting the Rest Channel TOT value to zero (disabled).
If a rest channel assignment is repeatedly force rotated from a specific repeater, while all other repeaters rotation happens normally, the software determines that the particular repeater has failed and reduces its rest channel preference to the lowest level. Consequently, the repeater in question is used less, to minimize the likelihood of the rest channel becoming unavailable on that repeater and blocking system access. In due course, if the repeater is found to be working then the preference level is reverted back to the RM/CPS configured level.[1]
Failure conditions where ARCR is useful
This feature is useful under the following conditions:
- On-channel interference on the repeater receive frequency, that is below the repeater RSSI threshold but high enough to prevent the repeater from receiving all radios call request.
- Failures in the receive path between the antenna and repeater (e.g. antenna; duplxer; multicoupler or jumper cables).
- Intermodulation products present on the repeater receive frequency.
- Desense (a.k.a. RF blocking),
- A defective repeater receiver (hardware failure).
Faults in the transmitter would be separately detected and the repeater would be removed from rest channel host contention.[2]
Configuration
ARCR does not require any configuration however the minimum and maximum time (see above) can be set via the following CPS/RM settings:
- The minimum possible ARCR time is equal to the SIT plus beacon interval - in this case 7920ms.
- The maximum possible ARCR time is equal to the Rest Channel TOT - in this case 8 minutes.
Rest Channel TOT is only visible in repeaters which have been configured to Capacity Plus operation.
See Also
References
- ↑ Adaptive Rest Channel Rotation. Retrieved 20.02.2024.
- ↑ Help, my Capacity Plus system is (almost) blocked! Retrieved 20.02.2024