Phase-Locked Loops for Wireles

This book is intended for the graduate or advanced undergraduateengineer. The primary motivation for developing the text was to present acomplete tutorial of phase-locked loops with a consistent notation. I believethis is critical for the practicing engineer who uses the text as a self-studyguide.Three years after the first printing, I discovered there was a need for asecond edition. I had taught several short courses from the text, anddiscovered that today’s engineers needed less time devoted to discrete-timetheory, but wanted more practical information on implementing phase-lockedloops. As a result, I have deleted discussions on topics such as multi-ratesampling and the Jury test, and replaced them with new content. Included inthe new material are additional loop filters and reduction of reference feedthrough in frequency synthesizers. Indeed, frequency synthesis is itself a new topic in the text.Since most hardware phase-locked loops utilize charge pumps, Ideveloped a new chapter that spotlights charge pumps and its complementarysequential phase detector. Several students in the short courses were askingfor design examples on delay-locked loops used to synchronize circuits onCPUs and ASICS. The second printing includes new material for this verypurpose.Another change was the increased use of Many of the original graphics have been replaced with graphics generated by MATLAB’s or Control System Toolbox. Since MATLAB has emerged as the leading simulation tool for the communications engineer, the graphics should be familiar and provide more information such as gain and phase margins. I have also taken the opportunity to correct typographical errors and further improve the consistency in notation.New material has been added on digital dividers. These devices caneasily dominate a frequency synthesizer’s noise floor, but the literature hasnot provided many solutions. In this second edition, I added sectionsdiscussing the origin of phase noise in digital dividers and possible solutions.Also included are some techniques to analytically estimate the phase noise ofa divider before it is even fabricated.In the past year, many students in the short courses have been asking fordesign help on optical phase-locked loops. A new chapter has been added onthis topic. Because many designers will be new to optical communications, Ihave included short sections discussing components such as lasers andphotodetectors. Since coherent phase-locked loops are so very difficult toimplement, I have included a section on automatic frequency control toprovide frequency-locking of the lasers instead of phase-locking.This second edition begins with the early history of phase-locked loops. Ibelieve that historical knowledge can provide insight to the development andprogress of a field, and phase-locked loops are no exception. Although allanalogphase-locked loops are becoming atypical, the continuous-time natureof analog loops allows an easy introduction to phase-locked loop theory.This foundation then allows us to proceed to the many implementations anddiscussions of phase-locked loops.I wish to thank the readers of the first edition for their many suggestionsand comments. Likewise the short course students have also strengthenedthis new edition with their participation and comments. I have tried toincorporate these suggestions within the intended scope of the text.