Wide dynamic range microphone

摘要

A microphone system has an output and at least a first transducer with a first dynamic range, a second transducer with a second dynamic range different than the first dynamic range, and coupling system to selectively couple the output of one of the first transducer or the second transducer to the system output, depending on the magnitude of the input sound signal, to produce a system with a dynamic range greater than the dynamic range of either individual transducer. A method of operating a microphone system includes detecting whether a transducer output crosses a threshold, and if so then selectively coupling another transducer's output to the system output. Some embodiments combine the outputs of more than one transducer in a weighted sum during transition from one transducer output to another, as a function of time or as a function of the amplitude of the incident audio signal.

主权项

1. A method of operating a microphone system for processing an incident audio signal, the method comprising:
providing a first microphone having a first dynamic range, wherein the first dynamic range has a first noise floor and a first top-end; providing a second microphone having a second dynamic range, wherein the second dynamic range has a second noise floor and a second top-end, and wherein the first noise floor is less than the second noise floor, the second top-end is greater than the first top end, and wherein the first dynamic range overlaps the second dynamic range; producing a first signal using the first microphone, and multiplying the first signal by a first weighting factor to produce a first weighted output signal; producing a second signal using the second microphone, and multiplying the second signal by a second weighting factor to produce a second weighted output signal; summing the first weighted output signal and the second weighted transducer output signal; and
providing the weighted sum to an output of the system, wherein the first weighting factor and the second weighting factor change in time, further wherein the sum of the first weighting factor and the second weighting factor remains constant, such that the relative composition of the weighted sum changes with time.