<title>Advanced signal processing method for interferometric fiber optic sensors with straightforward spectral detection</title>

The advanced method for straightforward spectral signal processing in interferometric fiber-optic sensors is presented. It is based on the analysis of the output spectrum of sensing interferometer in the domain of Fourier images. The main idea of the proposed method is to use the sensing interferometer with finesse > 2 and process the higher harmonics in addition to the first one. The technique does not suffer from power and spectral fluctuations of LED and sufficiently noise resistant.It is insensitive to the influence of parasitic interferometers appearing in the optical connectors, multimode fibers and other parts of the instrument. Devices based on such principles does not recalibration after switching on and further operation. The optimization of sensor's parameters based on numerical simulations is presented switching on and further operation. The optimization of sensor's parameters based on numerical simulations is presented.