INSIGHT
The use of leaky feeders in tunnels to improve mobile signals.
One of the most critical components in any communication system is the signal. When you need to send a signal through an obstacle, such as a tunnel or cave, the mobile phone needs the means to convert the radio signal into an electrical one that can travel through the tunnel intact. For this purpose, your phone can use leaky feeders, specially designed antennae that transmit radio waves with little loss through the tunnel. Because typical antennae suffer significant losses while travelling through a tunnel, they are only effective when very close to the transmitter. However, leaky feeders are very effective at extending the reach of a wireless signal throughout the tunnel.
There are several ways in which a leaky feeder can help to improve mobile communications in a railway tunnel. Firstly, leaky feeders allow for a much stronger signal to be emitted from the antenna much closer to the signal source. Increasing the signal strength can simultaneously achieve a greater coverage area. Second, leaky feeders can extend the useful range of a mobile phone much further than a “normal” antenna. Finally, they can reduce the power requirements for a signal by almost 100% compared with a conventional antenna.
There are several different types of leaky feeders, each of which provides a different level of performance. Some of these are better suited to the needs of specific applications than others, and choosing the right type of antenna can significantly affect a mobile system’s overall performance. For example, certain antenna types can be used for indoor networks, whilst others can be used outdoors in more challenging environments.
To maximise the performance of a leaky feeder, it should be kept clean and well-insulated. Regular maintenance is also required to ensure that there are no faults in the system that could interfere with its ability to transmit signals effectively.
Leaky feeders can help improve communications in tunnels, including those used in mining, oil and gas extraction, electricity generation and transport infrastructures such as railway lines and highways. The ability to extend the range of wireless signals through these antennas makes mobile communications in tunnels possible in situations where this was previously impossible.
Pan RF specialises in tunnel coverage design for mobile signal improvement and push-to-talk radio coverage.
