Train windows for better mobile reception
GLAZING: Siemens has developed a frequency-selective coating for train windows which is to improve onboard mobile reception by enabling better transmission of radio waves of certain frequencies. The windows will be installed in the fleet of 82 Desiro HC double-deck electric multiple-units that are to enter service in late 2018 on the Rhein-Ruhr-Express network.
An electrically conductive, transparent layer of metals or metal oxides is applied to the window panes. This is vapourised with lasers along lines arranged in a special structure, enabling radio waves in the 700 MHz to 3·5 GHz frequency range to pass through unhindered while signals at other frequencies are attenuated. According to Siemens, this covers not only current but also future mobile frequency ranges.