Parameters Measurement of Multiple Exponentially Damped Sinusoids With Sub-Nyquist Sampling

Measurement of parameters of multiple exponentially damped sinusoids (MEDS) signals is significant for nuclear magnetic resonance imaging and speech analysis systems. Traditional technologies require a large number of samples and heavy processing burden to estimate the parameters. In this brief, we propose a sub-Nyquist sampling and parameters estimation scheme for MEDS signals to address this problem. The proposed system consists of two parallel sampling channels, where the sampling clock of one channel is staggered with the other. The first sampling channel is used to estimate complex amplitudes, while the other is used to solve frequency ambiguity problem and determine the damping factors and pole frequencies. The proposed scheme enables parameters measurement of K components MEDS signals from as few as 3K samples, and it is also applicable to the scenario with unknown K. We also propose a hardware prototype to implement the proposed system. Simulation and experimental results demonstrate the effectiveness and noise robustness of the proposed scheme.