The article poses and solves the problem of creating an experiment processing method that is compact, high-precision and convent for use as part of an adaptive controller. These requirements are met by the author’s method of negative correlation/ the method uses the property of effective ACP. It consists in the fact that the frequency of natural oscillations of the system is significantly higher that the cutoff frequencies of the disturbing influences. Taking into account the low frequency, it turns out to be sufficient to measure only two ordinates for estimating the amplitude of oscillations and two ordinates for estimating their phase, followed by averaging over a set of periods. Each pair is separated by an interval equal to the half-period of the harmonic, and as a result, by a sign change. The sign change causes the use of the subtraction operation when averaging over the set, instead of the addition operation, the correlation moment is subtracted from the noise variance, an due to which it is accompanied by a significant decrease in the influence of the noise on the accuracy estimate.