Patent ID: 7630646

Claim:
A portable communication system for use by a user with a communication apparatus having an audio port, the system comprising: an infrared transmitter apparatus, wherein the infrared transmitter apparatus comprises: at least one audio port configured to receive an audio signal representative of received audio input from the communication apparatus, at least one infrared light emitting device, modulation circuitry operable to convert the audio signal to one or more constant width electrical pulses to drive the infrared light emitting device to transmit one or more corresponding constant width infrared pulses, wherein the modulation circuitry comprises: pulse width modulation circuitry to convert the audio signal using a carrier signal to one or more width modulated pulses, wherein the width of the one or more pulses is varied as a function of the audio signal; an edge detect circuit to detect the edges of the one or more width modulated pulses and generate constant width pulses based on the detected edges; and a pulse driver circuit to drive the infrared light emitting device; a microphone coupled to the at least one audio port of the infrared transmitter apparatus and operable to generate an audio signal from received sound input of the user, wherein the audio signal generated from received sound input of the user is provided to the audio port of the communication apparatus via the audio port of the infrared transmitter apparatus, and a transmitter housing enclosing the modulation circuitry and the microphone and upon which the at least one infrared light emitting device is mounted, wherein the transmitter housing is of a size smaller than the communication apparatus and configured to be removably coupled onto the communication apparatus; and an infrared receiver apparatus, wherein the infrared receiver apparatus comprises: an infrared light detection device to detect the one or more corresponding constant width infrared pulses and generate one or more electric signals representative of the detected infrared pulses, a speaker, demodulation circuitry operable to convert the one or more electric signals representative of the detected infrared pulses to an audio signal to power the speaker to produce a sound output, and a receiver housing enclosing the speaker and the demodulation circuitry and upon which the infrared light detection device is mounted, wherein the receiver housing is formed to be self-supported by the ear of the user.