FM Hearing-Aid Device Checkpoint 1 Brian Fang | Robert Johnson | Shoman Kasbekar | Zach Kovar | Arif Moktader

The Problem Hearing aid difficulties How can hearing performance be improved to enable speech distance evaluation? Project Goal: modify FM radio system in order to maintain a constant signal-to-noise ratio as the distance between the transmitter and receiver changes Amplification quality must be maintained throughout Detecting and expressing location of the transmitter relative to the receiver may be secondary function to research and develop hearing aid user has great difficulty discerning between auditory stimuli at near and far distances, particularly in unstructured settings such as houses. This project essentially strives to design a better hearing aid The goal of the project is to modify an FM radio system (wireless microphone) such that the distance between the transmitter and receiver can be detected and expressed to the user while maintaining audio amplification quality. Detecting and expressing location of the transmitter relative to the receiver may be secondary function to research and develop

Last Time Out Touched base with sponsors - cleared to continue with design plan Hearing aid company is based in Switzerland, so it took a while to schedule the meeting Goals are now much clearer - focus on distance Dr. Anne Marie Tharpe Dr. Daniel Ashmead Francois Marquis

Design Components Signal Filter Microphone Receiver Hearing Aid Transmits signal to Signal Filter Microphone Receiver Transmits filtered signal to Transmits signal to Transmits signal to Transmits distance data to Hearing Aid Transmitter Receives signal from Detects distance from Receives filtered signal from Located close to Detector User Speaker

Project Progress Code in development Future Goals MATLAB C Create a hardware box that implements filters in real time Will request funding for an Arduino to program and control input sound signals

Background Research Intensity loudness changes depending on distance Inverse relationship, extensively modeled Frequency perceived pitch changes depending on relative distance operates as a cue relative to distance - unusable at short distances Pinna effect Binaural (An Analysis of Cues to Auditory Depth Perception in Free Space) Physical acoustics reveals a bunch of stimulus correlates of sound source distance. These provide distance information detectable by ear. Intensity - commonly known, amplitude of sound changes with distance at an inverse relationship. This relationship has been extensively studied and Frequency - another cue in auditory depth perception, controversy as to how this cue influences distance judgments. Must consider frequency to operate as a cue in one manner at near differences and in another manner at far distances. Pinna effect delay from reverberant sound Binaural degree of phase difference

Basic Design Flowchart Location Scalars Reverb Filtering Input Output

GANTT Chart

Questions?