Liubchyk V. Development of theoretical foundations for improve the accuracy of radar for subsurface sensing

A basic theory of multifrequency phase measuring range of objects and their characteristics. When sensing objects by harmonic signals on different frequencies if several objects are vector of signal comes to the receiving device which represents the geometric sum of signal vectors which reflected from each object. The mathematical model of the total signal, which depending from vectors of total reflected signal and vector signal reflected from each object. The paper presents several methods for solving the problem of separation vector signals reflected from each object by mathematical transformations systems of nonlin-ear equations or study the characteristic points of amplitude-frequency and phase-frequency characteristics of total reflected signal. Investigated the accuracy and resolution of measurement methods multifre-quency phase range and characteristics of objects. The mathematical expres-sions calculating the parameters of probing signal. To speed up the process of sensing objects in a rapidly changing environment conditions (to meet the challenges of moving radar targets) proposed to be used as a probing signal representing the amount of harmonic components with multiple frequencies. An adaptive search method set initial phases of harmonic components that would minimize crest-factor.