A method for signal processing of an one-fiber two-mode interferometer

A solution of the problem of signal processing of a two-mode interferometer on the base of the optical fiber device providing interferometer modes interaction with following selection of lower order mode radiation is suggested. The dependence of amplitude of the interference signal on design parameters of a processing device is studied. The suggested waveguide spatial filter is shown to efficiently process a signal to intermode interference formed by one-fiber two-mode interferometers. It allows to broadly use interferometers of this type for reception of physical field parameters.