Behavioral Modeling of Delay-Locked Loops and its Application to Jitter Optimization in Ultra Wide-Band Impulse Radio Systems

This paper presents a behavioral model of a delay-locked loop (DLL) used to generate the timing signals in an integrated ultra wide-band (UWB) impulse radio (IR) system. The requirements of these timing signals in the context of UWB-IR systems are reviewed. The behavioral model includes a modeling of the various noise sources in the DLL that produce output jitter. The model is used to find the optimum loop filter capacitor value that minimizes output jitter. The accuracy of the behavioral model is validated by comparing the system level simulation results with transistor level simulations of the whole DLL