In the Indian Railways, the operational department heavily depends on VHF communication products, specifically walkie-talkies, to enable communication, whether the train is moving or stationary, and holds top priority in the Railway Transport Services.
One major challenge occurs when a train, along with its locomotive, is situated in a junction or terminal station. The VHF walkie-talkie signals experience interruptions due to the extensive metal and iron structures present around the station platform, which obstruct the radio Line of Sight (LoS). These structures with metal roofing are essential but can impact the signals.
To address communication challenges, the “Vardhak” system acts as a VHF two-way “Repeater,” working in a back-to-back fashion. Its primary function is to receive VHF signals from walkie-talkies used by both Drivers and Guards, at the nearest Vardhak Terminal. At the opposite end, another Vardhak Terminal receives and re-transmits the signal back on the original frequency of the driver-guard channel. This innovative solution ensures effective communication, even in areas with structural interference, ultimately improving the efficiency and safety of railway operations.