noun
signal beam; signal radio wave
Refers to a directed radio wave used for communication or signaling, such as in radar, navigation, or broadcasting.
レーダーは信号電波を発射して物体を探知する。
Radar emits a signal beam to detect objects.
電波 is a general term for radio waves, while 信号電波 specifically refers to a radio wave used as a signal.
Compound of 信号 (signal) and 電波 (radio wave).