Whenever a critical situation occurs, for instance a lone worker alarm being raised, it is of great importance that the TETRA radio network is alive. The Alive Check Module constantly verifies this through heart beats.

The TETRA Network Alive Check Module consists of a small, robust piece of hardware, the Alive Check Unit, and a software package installed on a PC.

Through heart beats it continuously checks the network and selected vital parts of the lone worker protection system. If it gets a faulty answer, the hardware will activate designated outputs.