Jeweller radio protocol: technology and capabilities

Updated

Jeweller is a radio protocol developed by Ajax System. It guarantees an uninterrupted interaction between the hub and security system devices.

Jeweller key features:

  • Reliability. Two-way radio communication features an algorithm to confirm the delivery of events and automatic frequency hopping in case of interference. Alarms are transmitted in less than 0.15 seconds.
  • Range. Jeweller provides up to 2,000 m of radio communication range between devices in an open area without interruptions. The range could be expanded to up to 3,800 m by integrating the ReX range extender.
  • Efficiency. The protocol uses time-division multiplexing of communication channels with a customizable frame size from 12 seconds. It features a short communication period and automatic regulation of signal strength. Jeweller extends the battery life of detectors to up to 7 years.
  • Protection. Block cipher encryption of data, frequency hopping, and device authentication during each contact prevent forgery of the equipment and signals.
  • Scalability. Up to 150 devices can operate within one security system without causing interference. Up to 5 of them can be radio range extenders. Ajax maximum coverage area can reach up to 35 km².

Jeweller radio protocol allows building security systems of any scale by connecting up to 150 devices to a single control panel, the hub. The maximum communication range of 2,000 meters is enough to cover up to 12 km² and protect apartments, homes, commercial properties, and offices.

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Using 5 ReX range extenders, the Ajax security system can cover up to 35 km² to protect hotels, storage facilities, estates, or factories.

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Jeweller uses optimal for security equipment radio frequencies: 868,0–868,6 MHz.

The two-way communication between the hub and connected devices provides many advantages. Detectors activate “armed” mode only when the hub sends the corresponding command. This way, they do not drain batteries in the meantime (in contrast, detectors of systems with one-way communication channels are always active). When the radio quality is good, devices lower the signal intensity of their transmitters.

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Automatic adjustment of signal intensity

Device configurations can be corrected from afar using the app instead of physical switches and terminals. But most importantly, the radio protocol guarantees the delivery of events. Detectors and control devices continue to transmit signals (alarms and commands) until they receive a confirmation about the successful delivery.

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Device settings can be configured in the app

Each system device establishes contact with the hub in a strictly defined moment and for a very brief period using an advanced technology for time-division multiplexing (based on TDMA). The rest of the time, the radio module is asleep to prolong battery life. A real-time clock is responsible for synchronizing all system devices. The interval between the communication sessions can be customized in the app from 12 to 300 seconds.

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Using the shortest interval allows users to discover the loss of connection with the detector in just 36 seconds

Data encryption, frequency hopping, and device authentication protect Ajax from sabotage. Trying to decrypt the signal, use the code grabber, or disarm the system by forging the SpaceControl keyfob would be in vain.

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During transmission, data is protected using block cipher encryption with dynamic key

Jeweller operation can be interrupted only by jamming all wireless signals near the protected property. But even in this case, the system wouldn’t be compromised. Ajax will quickly notify an alarm response company as well as users about the problem.

Learn more: What is Jeweller Signal Strength Test