When driving through tunnels, AM radio signals are blocked out by dense matter such as hills and buildings, resulting in drivers temporarily being unable to listen to their chosen radio station. In Hong Kong, BAI Communications, a specialist in designing, building, operating and maintaining the communications infrastructure, developed a rebroadcast system that reproduced the AM radio signals that had previously been blocked.
In order to achieve this, ViaLite was approached to provide a solution that could be integrated into the system. Its Blue OEM timing module was chosen as a viable option. Although typically used for GPS/GNSS timing applications, the module could be used for this application as it covers frequencies of up to 4.2 GHz. The end result was a system that could repeat the AM radio signals, which transmit in a frequency range of between 550 kHz and 1.72 MHz, allowing for uninterrupted coverage of AM radio signals.
ViaLite APAC Sales Manager John Meyers said that the diversity of form factors and frequency ranges in the ViaLite product range sometimes leads to creative implementations by their customers. BAI has used their popular Blue modules, originally intended to transport GPS signals over fiber, to carry and re-broadcast commercial AM radio signals in tunnels.
Click here for more details on the Blue OEM timing module.
