[en] This paper presents a theoretical treatment of the effect of strong radiation with an equidistant spectrum on two-level atoms. Based on an analysis of the effect of a strong bichromatic field on a quantum system, it is proposed to use multiquantum resonances in the absorption coefficient of the probe field and asymmetry of the absorption contour of this field when the perturbing field is shifted from the center of the line to determine the transition frequency of the atoms. As a consequence of the high sensitivity of the multiresonance structure in the absorption coefficient of the probe field to the shift of the perturbing field from the center of the line, it is shown that the method can be used not only in the rf region but also in the optical region for purposes of spectroscopy and magnetometry. 15 refs., 3 figs