Аннотация
Modern methods of band-stop filtering are sensitive to the influence of high-frequency single-frequency interference, which significantly distorts the shape of the informative signal. The noted feature is leveled by the system of narrow-band high-Q band-stop filtering developed in the article. The narrow-band high-Q band-stop filter is approximated by the Butterworth polynomial of the second degree and has the property of a closed circuit of the negative feedback loop, which, unlike the existing system, ensures high-precision processing of noisy measurements. The choice of this second-degree polynomial is justified by its maximally flat and symmetrical amplitude-frequency characteristic, the absence of pulsations in the interference suppression band and signal transmission, as well as the allocation of the lowest distortion for the selected order. The article under consideration presents the result of synthesis of a control system for a narrow-band high-Q band-stop filter with a variation of the correction coefficient of the feedback loop, which increases the efficiency of processing noisy measurements when introducing a value for this coefficient K = 0.1. It was revealed that the smallest value of this coefficient, compared to the value obtained when forming single feedback, significantly increases the value of the filter gain on its frequency response and thereby ensures narrowing of the suppression band to increase the quality factor of the rejection filter at the interference frequency. Moreover, a non-random and significant correlation relationship was found between the measured indicators, caused by a decrease in the accuracy and noise immunity indicators of the signal processing system with an increase in the values of the correction coefficient of the feedback loop of the rejection filter of the selected order. At the same time, understanding the discovered relationship used in developing a method for processing noisy measurements will significantly improve the accuracy and noise immunity of the signal processing system. The presented results, characterizing a statistically significant and non-random relationship, confirm the operability and functioning of the signal processing system, which determines the operation of a high-quality rejection filter when filtering single-frequency interference.