The AS-3422/ARN-99 upper TACAN antenna operates in which frequency band?

The AS-3422/ARN-99 upper TACAN antenna operates in which frequency band?

• A. S-band
• B. C-band
• C. L-band
• D. X-band

Answer: (C)

TACAN navigation radios operate in the L-band, around 1 to 2 GHz. The upper TACAN antenna for the ARN-99 is designed to transmit and receive in that L-band range, which is the frequency window allocated for TACAN/DME-type navigation signals. This band provides a practical balance between antenna size on aircraft, propagation characteristics, and compatibility with the TACAN system’s interrogation-and-reply scheme. The other bands listed—S-band, C-band, and X-band—are used for different purposes (radar, satellite links, and higher-frequency communications) and are not the bands allocated for TACAN navigation, which is why they aren’t correct for this antenna.

TACAN navigation radios operate in the L-band, around 1 to 2 GHz. The upper TACAN antenna for the ARN-99 is designed to transmit and receive in that L-band range, which is the frequency window allocated for TACAN/DME-type navigation signals. This band provides a practical balance between antenna size on aircraft, propagation characteristics, and compatibility with the TACAN system’s interrogation-and-reply scheme.

The other bands listed—S-band, C-band, and X-band—are used for different purposes (radar, satellite links, and higher-frequency communications) and are not the bands allocated for TACAN navigation, which is why they aren’t correct for this antenna.