High resolution pole-zero analysis of Parkinsonian speech

High-resolution analysis of voice speech signals in Parkinsonian patients using a pitch synchronous pole-zero model is introduced. A modified estimation error is defined, leading to an accurate and consistent determination of the excitation instants of the model. An infinite resolution in determining these instants, despite the finite sampling interval, is achieved by mapping the discrete (digitized) problem into a continuous one. The analysis is found to be useful in analyzing Parkinsonian speech where the goal is to detect and quantify the Parkinsonian tremor and rigidity from sustained voiced sounds. The speech analysis could accurately recover both components of the Parkinsonian disorder with a high correlation to a clinical diagnosis and electromyography measurements. It could also rank severity of the symptoms and classify between Parkinsonian patients and healthy subjects.