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Authority networks: Staying in touch during storms

Resilient radio networks keep agencies communicating despite power disruptions and extreme rain.

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Talk about stormy weather.

  • A major front sweeps across Belgium, shattering electricity pylons and mobile phone network antenna towers.
  • Finland suffers two major storms in the same month, leaving more than 10,000 households without electricity for several days.
  • Hungary witnesses a month's rainfall in just 24 hours.
  • Two people are killed when a storm hits Budapest.

Since 2010, Europe has seen several rough years for the weather. Storms have raged across the continent, causing disruptions in country after country.

So how do the authority networks cope in the aftermath of severe storms, with power disruptions and extreme rain threatening to interrupt transmissions?

1. Resilient radio networks: In the loop

Resilient radio network design can mitigate transmission problems. The right design ensures that there's always an alternative route from each base station to the network switch.

Connecting the base stations in one or more loops of microwave links or leased lines, for instance, means that every base station has at least two transmission routes. If one link fails, the transmission is automatically rerouted.

But a violent storm can bring down more than one connection at a time, cutting off base stations from the network switch. In this case, resilient radio networks' base stations continue to operate in fallback mode.

2. Authority networks: Something to fall back on

Fallback mode keeps users communicating - even when a storm cuts off their base station, and they're out of range from the rest of the network. Here's how it works on Airbus TETRA networks:

  • When a base station loses its connection, it automatically sends its users an SDS message about fallback mode.
  • Users have a fallback talk group pre-defined in their radios. Users operating in the affected area select this group to communicate with everyone else in the fallback area.
  • Users can also use regular talk groups or individual calls to reach others in the same area.

These measures - combined with extremely robust equipment - keep authority networks in action when public cellular networks fail. That means that those responsible for managing disruptions once the storm has passed can get on with their jobs whatever the weather.