Design of High-Order Phase-Lock Loops

The analysis, and design of third-order, (and higher) phase-locked loops (PLL) is difficult. This paper presents a novel approach to overcome these difficulties by allowing high-order loops to be viewed as a natural extension of lower order ones. This is accomplished by adding nested first-order feedback loops around a basic first-order loop filter. Our approach will also be related to the concept of PLLs with aided acquisition. The model presented has been implemented and tested in Simulink