Concentrating on second-order loops, this introduction to principles that can be applied to a wide range of phase- locked loop circuits is supplemented by a number of MATLABR simulation exercises that allow the reader to expand his or her knowledge of the circuit design process. Twenty chapters explore such topics as: loop components, response, and stability; transient and modulation response; acquisition; phase modulation by noise; response to noise modulation, representation of and loop response to additive noise; and parameter variation, nonlinear operation, and cycle skipping due to noise.