Subelement K: K – Aircraft— Topic 72: Aircraft Antenna Systems and Frequencies
Question 3-72K5
Element 3 (GROL)What is the frequency range of an aircraft’s radio altimeter?
Explanation
Aircraft radio altimeters operate in the 4250 MHz to 4350 MHz frequency band. This specific allocation is designated internationally for aeronautical radar altimetry, allowing these devices to precisely measure an aircraft's absolute height above terrain by transmitting a radio signal and measuring the time it takes for the reflection to return. This radar-based principle requires a dedicated, relatively wideband segment for accurate, real-time altitude readings.
The other options are incorrect as they correspond to different aeronautical services:
* **A) 962 MHz to 1213 MHz** is primarily used for Distance Measuring Equipment (DME) and TACAN.
* **B) 329.15 MHz to 335.00 MHz** is allocated for the ILS Glideslope.
* **D) 108.00 MHz to 117.95 MHz** is used for VOR navigation and the ILS Localizer.
Related Questions
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