German rail operator Deutsche Bahn trialled the use of laser-blasted windows to improve mobile coverage on its regional train services, with the transport player claiming zapped panes had vastly improved reception.

Showcasing the early results of pilots on a pair of vehicles in Bavaria and Berlin/Brandenburg, the company explained vehicles which had their windows retrospectively treated offered 100-times better signal than standard services.

The company is demonstrating the results of the trial at a local transport event later this week and is looking for partners for wider deployment.

Its long distance trains are already fitted with windows specifically designed to allow in mobile signals.

Deutsche Bahn board member for digitalisation and technology Daniela Gerd tom Markotten said its experts had “worked intensively” on the system.

She added panes which had been treated “allow mobile phone signals from all providers and all current and future mobile phone standards to enter the train almost unhindered”.

The company noted its regional train windows are currently covered with a thin layer of metal to protect against heat, though this hampers mobile phone signals. Deutsche Bahn noted the new technique involved a fine network structure being incorporated into the metal layer using a laser.

It added “The millimetre-fine lines only minimally change the thermal protection and thus the comfort on board; they are hardly visible to the naked eye.”