In
radiophysics Radiophysics (also modern writing "radio physics") is a branch of physics focused on the theoretical and experimental study of certain kinds of radiation, its emission, propagation and interaction with matter.
The term is used in the following majo ...
, the Luxemburg–Gorky effect (named after
Radio Luxemburg
RTL Radio is a German commercial radio station based in Berlin and the part of the RTL Group. It originated as the German language service of Radio Luxembourg, which began broadcasting after World War II from Luxembourg. It broadcasts adult c ...
and the city of Gorky (
Nizhny Novgorod
Nizhny Novgorod ( ; rus, links=no, Нижний Новгород, a=Ru-Nizhny Novgorod.ogg, p=ˈnʲiʐnʲɪj ˈnovɡərət ), colloquially shortened to Nizhny, from the 13th to the 17th century Novgorod of the Lower Land, formerly known as Gork ...
)) is a
phenomenon
A phenomenon ( : phenomena) is an observable event. The term came into its modern philosophical usage through Immanuel Kant, who contrasted it with the noumenon, which ''cannot'' be directly observed. Kant was heavily influenced by Gottfried ...
of
cross modulation
Intermodulation (IM) or intermodulation distortion (IMD) is the amplitude modulation of signals containing two or more different frequencies, caused by nonlinearities or time variance in a system. The intermodulation between frequency comp ...
between two
radio waves
Radio waves are a type of electromagnetic radiation with the longest wavelengths in the electromagnetic spectrum, typically with frequencies of 300 gigahertz ( GHz) and below. At 300 GHz, the corresponding wavelength is 1 mm (s ...
, one of which is strong, passing through the same part of a medium, especially a conductive region of atmosphere or a plasma.
Current theory seems to be that the conductivity of the ionosphere is affected by the presence of strong radio waves. The strength of a radio wave returning from the ionosphere to a distant point is dependent on this conductivity level. Therefore, if station “A” is radiating a strong amplitude modulated radio signal all around, some of it will modulate the conductivity of the ionosphere above the station. Then if station “B” is also sending an amplitude modulated signal from another location, the part of station “B’s” signal that passes through the ionosphere disturbed by station “A” to a receiver in line with both stations may have its strength modulated by the station “A” signal, even though the two are widely apart in frequency.
In other words, the ionosphere passes the station “B” signal with a strength that varies in step with the modulation (voice, etc.) of station “A.” This re-modulation level of the station “B” signal is usually only a few percent, but is enough to make both stations audible. The interference (both stations simultaneously received) goes away as the receiver is tuned slightly away from the frequency of “B.”
See also
*
Distortion
In signal processing, distortion is the alteration of the original shape (or other characteristic) of a signal. In communications and electronics it means the alteration of the waveform of an information-bearing signal, such as an audio signa ...
*
Radio propagation
Radio propagation is the behavior of radio waves as they travel, or are propagated, from one point to another in vacuum, or into various parts of the atmosphere.
As a form of electromagnetic radiation, like light waves, radio waves are affect ...
*
Notes
References
*.
*. In the paper "''An hereditary theory of the Luxemburg effect''" (English translation of the title), written only few years after the discovery of the effect itself, Dario Graffi proposes a theory of the Luxemburg effect based on Volterra's theory of hereditary phenomena.
Radio spectrum
{{radio-comm-stub