Optimised adaptive procedures and analysis methods for conducting speech-in-noise tests.

OBJECTIVE: Speech-in-noise testing is a valuable part of audiological test batteries. Test standardisation using precise methods is desirable for ease of administration. This study investigated the accuracy and reliability of different Bayesian and non-Bayesian adaptive procedures and analysis methods for conducting speech-in-noise testing. DESIGN: Matrix sentence tests using different numbers of sentences (10, 20, 30 and 50) and target intelligibilities (50 and 75%) were simulated for modelled listeners with various characteristics. The accuracy and reliability of seven different measurement procedures and three different data analysis methods were assessed. RESULTS: The estimation of 50% intelligibility was accurate and showed excellent reliability across the majority of methods tested, even with relatively few stimuli. Estimating 75% intelligibility resulted in decreased accuracy. For this target, more stimuli were required for sufficient accuracy and selected Bayesian procedures surpassed the performance of others. Some Bayesian procedures were also superior in the estimation of psychometric function width. CONCLUSIONS: A single standardised procedure could improve the consistency of the matrix sentence test across a range of target intelligibilities. Candidate adaptive procedures and analysis methods are discussed. These could also be applicable for other speech materials. Further testing with human participants is required.

Low-profile Button Sensor Antenna Design for Wireless Medical Body Area Networks.

A button sensor antenna (BSA) for wireless medical body area networks (WMBAN) is presented, which works through the IEEE 802.11b/g/n standard. Due to strong interaction between the sensor antenna and the body, a new robust system is designed with a small footprint that can serve on- and off-body healthcare applications. The measured and simulated results are matched well. The design offers a wide range of omnidirectional radiation patterns in free space, with a reflection coefficient (S11) of -29.30 (-30.97) dB in the lower (upper) bands. S11 reaches up to -23.07 (-27.07) dB and -30.76 (-31.12) dB on the body chest and arm, respectively. The Specific Absorption Rate (SAR) values are below the regulatory limitations for both 1-gram (1.6 W/Kg) and 10-gram tissues (2.0 W/Kg). Experimental tests of the read range validate the results of a maximum coverage range of 40 meters. Clinical Relevance- WMBAN technology allows for continuous monitoring and analysis of patient health data to improve the quality of healthcare services.

Design of Flexible Meander Line Antenna for Healthcare in Wireless Body Area Network Systems.

A flexible meander line monopole antenna (MMA) is presented in this paper. The antenna can be worn for on-and off-body applications. The overall dimension of the MMA is 37 mm x 50 mm x 2.37 mms, The MMA was manufactured and measured, and the results matched with simulation results. The MMA design shows a bandwidth of up to 1282.4 (450.5) MHz and provides gains of 3.03 (4.85) dBi in two operating bands, respectively, showing omnidirectional radiation patterns in free space. While worn on the chest or arm, bandwidths as high as 688.9 (500.9) MHz and 1261.7 (524.2) MHz, and the gains of 3.80 (4.67) dBi and 3.00 (4.55) dBi were observed. The experimental measurements of the read range confirmed. Clinical Relevance- Wireless Medical Body Area Network (WMBAN) technology allows for continuous monitoring and analysis of patient health data to improve the quality of healthcare services.

Binaural Signal Processing in Hearing Aids.

For many years, clinicians have understood the advantages of listening with two ears compared with one. In addition to improved speech intelligibility in quiet, noisy, and reverberant environments, binaural versus monaural listening improves perceived sound quality and decreases the effort listeners must expend to understand a target voice of interest or to monitor a multitude of potential target voices. For most individuals with bilateral hearing impairment, the body of evidence collected across decades of research has also found that the provision of two compared with one hearing aid yields significant benefit for the user. This article briefly summarizes the major advantages of binaural compared with monaural hearing, followed by a detailed description of the related technological advances in modern hearing aids. Aspects related to the communication and exchange of data between the left and right hearing aids are discussed together with typical algorithmic approaches implemented in modern hearing aids.

Ear-worn reference data collection and annotation for multimodal context-aware hearing instruments.

In this work we present a newly developed ear-worn sensing and annotation device to unobtrusively capture head movements in real life situations. It has been designed in the context of developing multimodal hearing instruments (HIs), but is not limited to this application domain. The ear-worn device captures triaxial acceleration, rate of turn and magnetic field and features a one-button-approach for real-time data annotation through the user. The system runtime is over 5 hours at a sampling rate of 128 Hz. In a user study with 21 participants the device was perceived as comfortable and showed a robust hold at the ear. On the example of head acceleration data we perform unsupervised clustering to demonstrate the benefit of head movements for multimodal HIs. We believe the novel technology will help to push the boundaries of HI technology.