Title :
Analysis of Injection Pulling in Phase-Locked Loops With a New Modeling Technique
Author :
Sancho, Sergio ; Ponton, Mabel ; Suarez, Almudena ; Ramirez, Franco
Author_Institution :
Commun. Eng. Dept., Univ. of Cantabria, Santander, Spain
Abstract :
A new formulation is presented for the analysis of phase-locked loops (PLL). It is based on the use of a realistic reduced-order model for the voltage-controlled oscillator, extracted from harmonic-balance (HB) simulations. An HB formulation of the reduced-order PLL equations enables an efficient analysis of the PLL in unlocked conditions, and therefore, prediction of common hysteresis phenomena. The injection-pulling effects in the presence of interference signals are analyzed taking into account the nonlinearity of the phase detector. The interfered PLL in locked conditions is analyzed with a single-tone HB formulation of the reduced-order system, whereas a two-tone HB analysis is used for the analysis in unlocked conditions. The frequency-domain formulation enables an accurate and efficient prediction of the effect of the interferer on the hold-in and lock-in ranges, here investigated, to our knowledge, for the first time. The analysis has been successfully applied to a PLL operating at 5.3 GHz.
Keywords :
frequency-domain analysis; microwave oscillators; phase detectors; phase locked loops; reduced order systems; voltage-controlled oscillators; VCO; common hysteresis phenomena; frequency 5.3 GHz; frequency-domain formulation; harmonic-balance simulations; hold-in ranges; injection-pulling effects; interference signals; lock-in ranges; modeling technique; phase detector; phase-locked loops; reduced-order PLL equations; single-tone HB formulation; two-tone HB analysis; unlocked conditions; voltage-controlled oscillator; Equations; Integrated circuit modeling; Mathematical model; Phase locked loops; Stability analysis; Voltage-controlled oscillators; Injection pulling; phase-locked loop (PLL); voltage-controlled oscillator (VCO);
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2013.2241786