Root Locus Analysis of Differential Control PLL Discriminator

Abstract

 The root locus of the third-order and fourth-order differential control phase-locked loop discriminators are analyzed. With the help of computer-aided analysis and theoretical research, the parameter boundaries that cause the root-locus jump of the fourth-order loop under different time constant conditions are determined. This will provide a useful basis for the research and design of the time-domain indicators of the transient response of this low-threshold phase-locked loop discriminator.