A phase-locked loop

Abstract

In this article, a phase-locked loop (PLL) is introduced. The proposed PLL, denoted by NPLL, is similar to the standard PLL except that it incorporates a nonlinear element and a low pass filter in its loop. The NPLL outperforms the standard PLL: (i) it has a large acquisition range, i.e., it can achieve locking in situations where the standard PLL cannot; and (ii) it achieves locking much faster than the PLL. The superior performance of the NPLL is due to the nonlinear element and the low pass filter added to the loop. Results of many tests, only three of which are reported in this article, show the superior performance of the NPLL.