Still in Womb: Intrauterine Acoustic Embedded Active Noise Control for Infant Incubators

Abstract

Excessive noise in neonatal care units and inside incubators can have a number of detrimental effects on an infant's health. We proposed a novel, audio-integrated approach to achieve active noise control (ANC) for infant incubators. We also presented the implementation of the robust, nonlinear filtered-X least mean M-estimate algorithm, for reducing impulsive interference in incubators. The healthcare application is further enhanced by integrating the “womb effect”, that is, by using intrauterine and maternal heart sounds, proven to be beneficial to infant health, for soothing the infant and masking the residual noise. A computer model for audio-integrated noise cancellation utilizing experimentally measured transfer functions is developed for simulations using real medical equipment noise. The simulation of the audio integrated ANC system produced optimal results and the system was further validated by real-time experiments to be robust and efficient.

Active control of impulsive noise using a nonlinear companding function

“…Active noise control (ANC) has received significant research efforts over the past decades [1][2][3][4][5]. The principle of ANC is based on attenuation of unwanted disturbance noise (primary noise) by applying a controllable secondary source to destructively cancel the disturbance noise.…”

Data-reusing-based filtered-reference adaptive algorithms for active control of impulsive noise sources

“…10, and where three sections (as mentioned in (27)) are plotted in different panels for the sake of clarity of presentation. The parameter p in the FLOM-based algorithms is selected as p ¼ 1:69 as in Case 1, 4 ¼ 1:7). (a) FxLMP algorithm [10], (b) ThFxLMP algorithm [14], (c) NSS-GFxLMP algorithm [16], and (d) Proposed-II algorithm.…”

“…In practice, the impulsive noises are often due to the occurrence of the noise disturbances with a low probability but large amplitude. The impulsive noise exists in many real-world applications such as punching and stamping machines in manufacturing plants, presses, combustion engines, pile drivers, IV pump sounds in the hospitals [4,5]. Furthermore, it can be shown that a fairly general type of noise signals, for example road traffic noise, office noise, etc., can be more accurately described as SaS processes rather Gaussian ones [6].…”

Applications of Adaptive Filtering: Recent Advancements in Active Noise Control

“…For example, infant incubators are used in neonatal intensive care units (NICU) to increase the survival of premature and ill infants. The application of ANC for reducing incubator noise in NICU was reported in (Liu et al, 2008), where a nonlinear filtered-X least mean M-estimate algorithm is developed for reducing impulse-like noise in incubators. In Section 3 we have presented some robust algorithms for ANC of impulsive noise sources, and theoretical performance analysis, real-time experiments, and development of more effective ANC algorithms is open for further research.…”