Definition
Reduced in strength or intensity. In radar use, a signal is attenuated when its energy is weakened as it travels through the atmosphere, passes through precipitation, or is partially absorbed or scattered by objects in its path, resulting in a weaker return at the receiver.
Plain English
Made weaker. The radar signal loses some of its power as it travels out and back, especially when it has to pass through rain, clouds, or other obstacles.
Context Anchor
Seen in primary radar discussions when explaining why a radar signal or target display may become weaker with distance, weather, or objects in the signal path.
Derivation
From the Latin 'attenuare', meaning 'to make thin'. The original sense of thinning something out helps here — a radar signal isn't thinned physically, but its strength is thinned down as it travels and interacts with the atmosphere.
Why Pilots Care
Attenuation reduces radar detection range and return strength, directly affecting the ability to see weather or traffic.
Analogy
A flashlight beam looks weaker after it passes through fog. The light is still there, but it has been reduced before it reaches your eyes.
Intuition Check
Attenuated does not mean completely blocked or stopped. It means weakened; some signal may still get through or return, but with less strength.
Example Sentence 1
The radar return from the distant aircraft was attenuated by the heavy rainfall between the antenna and the target.
Example Sentence 2
The controller noted the attenuated echo and asked the pilot to confirm position by other means.