SELF CALIBRATING MULTI-ELEMENT DIPOLE MICROPHONE

摘要

A self calibrating dipole microphone formed from two omni-directional acoustic sensors. The microphone includes a sound source acoustically coupled to the acoustic sensors and a processor. The sound source is excited with a test signal, exposing the acoustic sensors to acoustic calibration signals. The responses of the acoustic sensors to the calibration signals are compared by the processor, and one or more correction factors determined. Digital filter coefficients are calculated based on the one or more correction factors, and applied to the output signals of the acoustic sensors to compensate for differences in the sensitivities of the acoustic sensors. The filtered signals provide acoustic sensor outputs having matching responses, which are subtractively combined to form the dipole microphone output.

主权项

1. A microphone, comprising:
a first acoustic sensor having a first output; a second acoustic sensor having a second output; a sound source acoustically coupled to the first and second acoustic sensors, the sound source comprising an input; an enclosed sound conducting channel spanning continuously from the sound source to the first acoustic sensor and the second acoustic sensor, the enclosed sound conducting channel forming a first acoustic transmission path from the sound source to the first acoustic sensor and a second acoustic transmission path from the sound source to the second acoustic sensor; a processor electrically coupled to the input, the first output, and the second output, the processor being configured for:
activating the sound source to produce an acoustic calibration signal;receiving a first output from the first acoustic sensor generated in response to the acoustic calibration signal;receiving a second output from the second acoustic sensor generated in response to the acoustic calibration signal; anddetermining one or more correction factors based on the received first output and the received second output.