Signal delay reconstruction method based on dynamic index and complex-coefficient lagrange interpolation

This paper presents a large-range, high-precision and continuously variable delay reconstruction method for wideband and arbitrary bandlimited signal, which combines dynamic index technique with complex-coefficient Lagrange interpolation technique. The method samples time-continuous bandlimited signal and stores samples in sequence. It manages to obtain the high-precision delay parameters of every sampling period from desired delay to compute the so-called index position variable and interpolator parameters. It dynamically indexes and chooses a set of samples to implement piecewise complex-coefficient Lagrange interpolation for reconstructing the delayed sequences. The time-continuous delay reconstruction signal can be simply accomplished through digital-to-analog conversion. The mathematical model of the method and its transformed form is given, and the arithmetic of dynamic index and complex-coefficient Lagrange interpolation is derived. Simulation and test results show the validity and performance of the method.