Project Details

Problem

Background Goal Functional Requirements Specifications Constraints

Background

EarTalk is a wireless communication device used in high-noise environments where hearing protection is necessary. The current EarTalk system consists of a microphone and a speaker embedded in separate earplugs along with external circuitry to restore the natural quality of the user’s voice. This current system is too large and uses wires to connect to the microphone/speaker.

The Center for Disease Control (CDC) in Cincinnati, Ohio created the current EarTalk system. The microphone embedded in the earplug senses the user’s voice through bone vibrations in the head, converts it to an electrical signal, and then sends the signal via wire to a 2-way radio. The CDC is collaborating with AudioVibe to create a wireless EarTalk system. This wireless system will provide a clear, discrete method of communication for use in high-noise environments. Clear communication is critical in applications such as firefighting where it can mean the difference between life and death.

Goal Back to top

The goal of this project is to design and implement a low-power, compact wireless circuit to transmit speech from the user’s ear to a re-transmitter approximately 5 to 8 inches away from the ear. This circuit should be small enough to fit within the earplug and send the user’s voice signal to a relaying transmitter on the user's helmet.

Functional Requirements Back to top

1) Sense and convert speech inside ear	Must sense speech from inside the ear canal and convert the acoustic signal to an electrical signal.
2) Wireless	Must transmit signal from the ear to a re-transmitter wirelessly.
3) Low power	Must operate on a minimal amount of power.

Specifications Back to top

1) Sense and convert speech inside ear	Transducer, circuit, and battery must be small enough to fit in or closely around the ear and provide a good quality acoustic to electric conversion.
2) Wireless	Must transmit signal wirelessly from ear to a re-transmitter approximately 5-10 inches away.
3) Low power	Must remain operational for no less than 10 hours with a 1.3-volt hearing aid battery.

Constraints Back to top

A. Configuration	The instrumented earplug should fit entirely within the ear with little or no protrusion outside the ear.
B. Transducer	A low-power transducer should be used. Avoid electromagnetic loudspeakers because they consume a relatively large amount of power.
C. Modulation technique and carrier frequency	No constraints. However, factors such as channel noise, helmet material, transmission distance, etc. should be considered.
E. Antenna	Due to space limitations, an antenna should be very small or non-existent.

Questions or concerns: audiovibe@uidaho.edu