Tropospheric Reflections

Small discontinuities in dielectric constants at the boundaries of different air masses often cause tropospheric reflection of VHF, UHF and microwave signals. Many observers assumed those reflections must be due to tropospheric ionization when they were first discovered, but meteorological sounding balloon observations in the 1930's found that the ionization that would be required does not exist in the troposphere. It also was determined at that time that dielectric constant discontinuities required to produce observed results can be readily accounted for by air masses of different temperature and moisture content in proximity to each other. ©2004 Tigertek, Inc. All rights reserved.

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