transmitter over the wires. The VHF transmitter, in turn, transmits all events and
alarms to the CMS via a radio channel.
Events can be transmitted to the CMS via the internet and vhfBridge in parallel.
Transmission via the internet works as the main channel because of greater
reliability and informativity. The transmitted events may contain the zone
number of the triggered detector, group number, user number, and other data.
vhfBridge works as a backup communication channel and duplicates all events
transmitted via the internet. The delivery speed of events and alarms in both
cases does not exceed 1 second.
An example of the algorithm of actions in case of an alarm from a
MotionProtect motion detector:
1. MotionProtect has detected an alarm.
2. MotionProtect transmits the alarm to the hub via the Jeweller radio
protocol.
3. The hub receives the MotionProtect alarm and transmits it to vhfBridge via
the Jeweller radio protocol.
4. vhfBridge receives the alarm from the hub and transmits it to the third-party
VHF transmitter over a wired connection.
5. The VHF transmitter receives the alarm and transmits it to the radio receiver
on the CMS side via the radio channel.
6. The radio receiver receives the alarm and transmits it to the CMS software.
7. The CMS receives and processes the alarm.
