Three experimental measures of a digital beamforming signal processing algorithm.
Three studies were conducted to evaluate a prototype nonlinear digital beamforming hearing aid. The experiments all used contextually rich speech materials and subjective analysis methods and, on that basis, are grouped together in this report. In experiment 1, the beamforming was done off line and subjects wore their own hearing aids in an attempt to determine whether the processing reduced the interference of noise jammers. In experiments 2 and 3, subjects used portable, head-worn, real-time devices. The results of these experiments showed improvements in perceived ease of speech understanding for these types of subjective measures and lend encouragement to further development of this type of binaural hearing aid. Additional work is also required to develop methods of physically characterizing the nonlinear directional properties of the algorithms.