Calibration of Phase Shifters on Basis of Vector-Sum Signals

Abstract

Attenuators and phase shifters which are the circuits for amplitude-phase distribution control are key elements of antenna arrays. Dispersion of technology parameters results in deviation of the characteristics of integral circuits from rated values that requires application of the techniques for this effect compensation. In this paper there are considered the methods for development and calibration of the circuits in a basis of vector-sum signals allowing to modify both amplitude and phase of input high-frequency signal. It is proposed the method of calibration on a basis of interpolation of measured dependences of absolute value and phase of transfer factor on controlling voltage. Application of proposed method for calibration of vector phase shifter with operating frequency band 2.8–3.2 GHz fabricated with 0.18 mm CMOS allows to provide mean square deviation of phase error is not greater than 0.9°. At that amount of required measurements is 20 times decreased comparing known approach on a basis of measurement of all amplitude-phase states.