What does a duplexer do in a radar system?

In a radar system, a duplexer functions as an electronic switch that allows the same antenna to be used for both transmitting and receiving signals. During the transmission phase, the duplexer connects the transmitter to the antenna, enabling the radar to emit radio frequency signals. Once the transmission is complete, the duplexer rapidly switches the connection to route incoming signals from the antenna to the receiver. This capability is crucial because it allows for efficient use of the antenna without requiring separate antennas for each function, thereby saving space and reducing system complexity.

The other options describe functions that are not typically associated with a duplexer's role. For example, amplifying the transmitted signal, filtering out noise, or converting signals to analog format are tasks usually performed by other components within the radar system.