Interferences are superpositions of waves caused by interactions with closely adjacent or the same frequencies. These interferences occur in all frequency ranges. Inacoustics as well as in the transmission of high frequencies, microwaves or optical signals in optical transmission.
In interference, the resulting wave from two waves of the same frequency is the algebraic sum of the two waves. If both waves have the same phase, this can lead to addition and, in extreme cases, to doubling. If the two waves are in opposite phase, this can also lead to extinction, i.e. extinction. The interference principle is used in interference filters and dichroic filters.
Interference has a detrimental effect on the transmission of radio, television and mobile radio, but can also severely impair transmission in local networks if, for example, Ethernet is incorrect or not terminated.