Measurement Uncertainty of Precise Interpolating Time Counters

This paper presents a comprehensive analysis of measurement uncertainty of a wide class of precise time interval counters based on the most common two-stage time interpolation method. All nonnegligible sources of errors are discussed, including the quantization process, nonlinearity of time interpolators, timing jitter induced by elements of signal paths as well as inherent jitter of input pulses, and reference clock signal. A formula of the total measurement uncertainty and several design suggestions aiming at improving the time counter accuracy and precision is provided.