Comparison between electroglottography and electromagnetic glottography

Abstract

Newly developed glottographic sensors, utilizing high-frequency propagating electromagnetic waves, were compared to a well-established electroglottographic device. The comparison was made on four male subjects under different phonation conditions, including three levels of vocal fold adduction (normal, breathy, and pressed), three different registers (falsetto, chest, and fry), and two different pitches. Agreement between the sensors was always found for the glottal closure event, but for the general wave shape the agreement was better for falsetto and breathy voice than for pressed voice and vocal fry. Differences are attributed to the field patterns of the devices. Whereas the electroglottographic device can operate only in a conduction mode, the electromagnetic device can operate in either the forward scattering (diffraction) mode or in the backward scattering (reflection) mode. Results of our tests favor the diffraction mode because a more favorable angle imposed on receiving the scattered (reflected) signal did not improve the signal strength. Several observations are made on the uses of the electromagnetic sensors for operation without skin contact and possibly in an array configuration for improved spatial resolution within the glottis.

Glottal inverse filtering analysis of human voice production — A review of estimation and parameterization methods of the glottal excitation and their applications

“…Measurements of the vibrating vocal folds is difficult, as the oscillation can neither be examined directly due to the hidden position of the vocal folds nor be observed without aids because of the high speed of the oscillations. Instrumentation to carry out the measurements of the vibrating vocal folds has been developed during the recent decades and the methods developed are based, for instance, on visual (e.g., Sonesson 1959), electrical (e.g., Lecluse et al 1975) and electromagnetic methods (Titze et al 2000). Visual analysis is widely used especially in clinical investigation of voice production.…”

Development of three‐dimensional laryngostroboscopy for office‐based laryngeal diagnostics and phonosurgical therapy

“…Imaginable for additional optimization of 3D‐based diagnostic procedures is the combination with other established examination methods, such as electroacoustic voice analysis. Compared to the known electroglottography, an advanced examination instrument could be created . Furthermore, innovative endoscopic imaging techniques and new optical visualization modes are currently developed and tested to enhance the diagnostic sensitivity and specificity, especially in precancerous lesions .…”

The tongue and ear interface

“…Non-Audible Murmur microphone [15,16,26] 4. Electromagnetic and vibrational sensors of glottal activiy [27,28,32,36] 5. Surface electromyography (sEMG) or the muscles of the larynx [19,20,21,23,33] 6.…”