Which radar component allows the same antenna to be used for both transmitting and receiving?

The correct choice is the duplexer. In radar systems, a duplexer serves a crucial role by allowing the same antenna to be used for both transmitting and receiving radio signals. This is important because it enables efficient use of a single antenna, which reduces equipment size, weight, and complexity.

A duplexer functions by allowing high-powered transmit signals to pass from the transmitter to the antenna while simultaneously ensuring that the weaker received signals can travel from the antenna back to the receiver. It effectively isolates the transmitter from the receiver so that the strong transmission does not interfere with the reception of the signal. This two-way functionality is key in many radar applications, making the duplexer an essential component.

In contrast, other components like a splitter or combiner typically handle the distribution of signals but do not manage the transmission and reception through the same antenna. A transceiver combines both transmitting and receiving functions but still requires separate paths or antennas for each operation in typical applications. Thus, the duplexer stands out as the specialized component that fulfills this dual role efficiently.