Attenuation – Definition and Pronunciation
What is Attenuation?
Attenuation is the decrease in intensity of a signal, beam, or wave as a result of absorption of energy and of scattering of the path to the detector, but excluding the reduction due to geometric spreading. Attenuation is expressed in dB.
Examples of Attenuation
For frequencies above 20 GHz the standard mechanisms include attenuation of the radio waves due to absorption by atmospheric gases (water vapor and oxygen).
From “Atmospheric Boundary Layer and Basics of the Propagation Mechanisms”.
The Ka-band service will be supported by the integration of an L-band FleetBroadband (FBB) backup service; with this approach, reliability will not be compromised in case of heavy rain, causing signal attenuation in the Ka-band, especially for maritime applications (aeronautical IFC services are less subject to rain-related issues, since flight below 10 000 ft is usually restricted to a few minutes after takeoff and a few minutes before landing).
From “Aeronautical Mobility Services”.
One would determine which rain zones the earth station antenna in question is located by consulting the table to determine the precipitation rate in mm/hr and the graph to determine the attenuation.
From “High Throughput Satellites (HTS) and KA/KU Spot Beam Technologies”.
Pronunciation of Attenuation
