Final answer:
In the Monopulse Secondary Surveillance Radar (MSSR), when the operational on-line channel fails, the system can switch to a back-up channel to continue functioning, although with reduced performance. The back-up channel utilizes redundant hardware and a secondary antenna to receive signals from the aircraft transponder.
Step-by-step explanation:
In the Monopulse Secondary Surveillance Radar (MSSR), when the operational on-line channel fails, the system can switch to a back-up channel to continue functioning. The back-up channel is usually designed to maintain basic surveillance capabilities, allowing the radar to still detect and track targets in the absence of the primary channel.
This is achieved by using redundant hardware and a secondary antenna, which receives signals from the transponder of the aircraft. The system combines the received signals from the primary and secondary channels to generate accurate target information.
During the failure of the operational on-line channel, the system may experience a decrease in its overall performance, such as reduced accuracy or tracking capabilities. However, it will primarily depend on the design and capabilities of the specific MSSR system.