Closed-loop automatic phase control

The dynamics of a closed-loop method of phase control of a local oscillator are discussed in this paper. An equivalent circuit is derived, on which further analysis of the system is based. While a linearized system and a system which uses time domain filtering have appeared in the literature, this paper presents a new, simple, and direct approach to the optimization of the system. A more general analysis is given and the general requirements for the nonlinear element and the subtraction device are pointed out. A method of design for the equalization filter is given. The theory is verified with experimental results.