A little-discussed problem with modern glass, namely is that it is increasingly difficult for radio signals to pass through it. Siemens-developed technology is going to to limit the frequency loss for mobile signals passing through the windows, in turn significantly boosting it. NTT Docomo is trying to combat the thermal coating issue, by evaluating aerogel, which it described in a statement as a “light, porous material”. A third possibility involves using (Li-Fi) specialist LINXC Bridge which beam signals indoors using light rather than radio.