Patent · US Expired

Low-noise directional microphone system

US7409068B2 · kind B2 · utility

13Cited by
40References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 6, 2003
Grant dateAug 5, 2008
Priority date
Expiry dateMar 8, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04R2430/21
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A low-noise directional microphone system includes a front microphone, a rear microphone, a low-noise phase-shifting circuit and a summation circuit. The front microphone generates a front microphone signal, and the rear microphone generates a rear microphone signal. The low-noise phase-shifting circuit implements a frequency-dependent phase difference between the front microphone signal and the rear microphone signal to create a controlled loss in directional gain and to maintain a maximum level of noise amplification over a pre-determined frequency band. The summation circuit combines the front and rear microphone signals to generate a directional microphone signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.