FIELD: measurement technology. SUBSTANCE: phase difference of two filtered off analyzed signals is determined by dividing values of one signal by other, quotient signal f(t) is recorded, its two instant values are measured on selected half-wave interval of divisor signal at time moment t1 and t2 equally spaced apart through quarter of half-cycle from center of selected half-wave, and phase shift between signals is determined from equation given in description of invention. This provides for low measurement error even at infralow frequencies, determination of signal-to-signal phase ratio is not required, distortions may be admitted in one of signals in region of its extreme values not influencing measurement accuracy. EFFECT: improved measurement accuracy. 1 dwg
