APPARATUS, SYSTEMS, AND METHODS FOR CALIBRATION OF MICROPHONES

摘要

The disclosed apparatus, systems, and methods provide a calibration technique for calibrating a set of microphones. The disclosed calibration technique is configured to calibrate the microphones with respect to a reference microphone and can be used in actual operation rather than a testing environment. The disclosed calibration technique can estimate both the magnitude calibration factor for compensating magnitude sensitivity variations and the relative phase error for compensating phase delay variations. In addition, the disclosed calibration technique can be used even when multiple acoustic sources are present. The disclosed technique is particularly well suited to calibrating a set of microphones that are omnidirectional and sufficiently close to one another.

主权项

1. An apparatus comprising:
an interface configured to receive a first digitized signal stream and a second digitized signal stream, wherein the first digitized signal stream and the second digitized signal stream correspond to an acoustic signal captured by a first microphone and a second microphone, respectively; a processor, in communication with the interface, configured to run a module stored in memory, wherein the module is configured to:
determine a first time-frequency representation of the first digitized signal stream and a second time-frequency representation of the second digitized signal stream, wherein the first time-frequency representation indicates a phase of the first digitized signal stream for a plurality of frequencies and for a first time frame, and wherein the second time-frequency representation indicates a phase of the second digitized signal stream for the plurality of frequencies and for the first time frame;compute a first parameter that indicates a direction of arrival of the acoustic signal based on a relative arrangement of the first microphone and the second microphone, and the first time-frequency representation and the second time-frequency representation at a first of the plurality of frequencies at the first time frame; anddetermine a first relative phase error between the first microphone and the second microphone for the first time frame for the first of the plurality of frequencies based on the first parameter, the first time-frequency representation, and the second time-frequency representation at the first of the plurality of frequencies at the first time frame.