What frequency band does the localiser use?

The localiser, which is an essential component of an Instrument Landing System (ILS), operates within the frequency range of 108-112 MHz in the VHF band. This specific frequency range is delineated for use in aviation to ensure reliable and precise navigation for aircraft approaching a runway. The localiser provides lateral guidance to pilots as they align with the centerline of the runway during the final stages of landing, enhancing safety and accuracy in challenging weather conditions.

The choice of 108-112 MHz is specifically designated for localisers to minimize interference with other aircraft systems and terrestrial communication. Moreover, this range allows for sufficient signal strength and clarity, which are crucial for aircraft avionics to interpret and follow the localiser signals correctly. The use of the VHF band rather than UHF or any other frequency bands aligns with the requirements for line-of-sight communication and effective propagation characteristics needed for aviation navigation.