We carried out an analysis of periodic components of flux variability on the basis of the long-term monitoring of the active galaxy nuclei 3C454.3, 1633+382 and 3C120 observed at the Crimean Astrophysical Observatory during 1985—2008 at 22.2 and 36.8 GHz. Long-period components of the variability (12—14 years) are determined in the sources and are interpreted as the precessional motion of the central body in a double system. The detected short-period components of the variability (1.5—3 years) are compared using the models of the orbital periods for motion in the central supermassive black holes. The brightest representative active galaxies observed as nonstationary sources in a broad range of wavelengths are binary systems of supermassive black holes at the evolution stage close to coalescence. The following parameters for the supposed binary black-hole systems are determined: the masses of the central object and its companion, the radius of the companion’s orbit, and coalescence time. The ratio of the masses of the double systems for all the sources is less than 10, that points to a strong gravitation effect of the companion on the central black hole. The motion velocities of the central body is about 1000 km/s. This fact re quires an additional account in the calculation of the rate of the accretion on the central body. The orbital radii of the companions fall in the narrow range between 4·10¹⁶ and 6·10¹⁶ cm, which points to a strong interrelation between the masses of the binary systems and orbit sizes and the energy loss for gravitation radiation. Within the orbit of the com pan ion during its motion through the accretion disk, a high temperature of surrounding gas is reached. High density of the medium which is (10⁹—10¹⁰) cm^-3, combined with magnetic fields and shock waves spreading in the accretion disk, creates some conditions for powerful energy release in directed jets.