Patent ID: 7751575
Filing Date: 2010-07-06
Classification: H04R

Abstract:
1. A microphone system for communication devices comprising: a. a first input sound port that leads into a first omnidirectional microphone element; b. a second input microphone port that leads into a second omnidirectional microphone element positioned near the first microphone element; and c. a signal flow processor electrically connected to the first and second microphone elements; wherein the signal flow processor provides an electrical time delay (“τ”) only to the first microphone element and provides a compatible amplitude gain to the second microphone element; wherein τ=(w−u)/c, the variable “w” equals the distance between the receiver and the second sound port, the variable “c” equals approximately 345,000 millimeters per second, and the variable “u” equals √{square root over ( )}[w wherein the signal flow processor subtracts the outputs of the first and second microphone elements to create a null that reduces external acoustic coupling.