Definition of the term Intermodulation Selectivity of a radio receiver

Intermodulation selectivity of a receiver: the capability of a radio receiver to receive a desired modulated radio frequency signal at its nominal frequency without significant quality degradation when two or more interfering signals, whose frequencies have a specific relationship to the desired signal frequency, are present at its input.

Intermodulation — a phenomenon in which interference signals appear at the output of the receiver when two or more unwanted signals, whose frequencies do not coincide with those of the main and adjacent reception channels, are applied to its input. Under these conditions, the receiving path may generate an intermodulation interference signal whose frequency matches that of the desired signal or falls within the passbands of the receiver’s adjacent channels. Such interference is processed together with the desired signal, which results in deterioration of the received message quality.

Intermodulation response rejection — a quantitative measure of a receiver’s ability to receive the required signal on the working channel frequency in the presence of two or more interfering signals having a specific frequency relationship with the desired signal.

Related articles:
Modulation Techniques, Emission Classification