Noise cancelling microphone

Abstract

A noise cancelling microphone configured to cancel ambient noise is disclosed herein. The noise cancelling microphone includes a first micro-electro-mechanical systems (MEMs) microphone coupled to a first surface of a printed circuit board (PCB), a second MEMs microphone coupled to a second surface of the PCB opposite the first surface, and an audio signal processor electrically coupled to the first MEMs microphone and the second MEMs microphone. The first MEMs microphone is configured to receive a first set of one or more sound waves approaching the noise cancelling and output a first electrical signal. The second MEMs microphone is configured to receive a second set of one or more sound waves and output a second electrical signal. The audio signal processor is configured to receive the first electrical signal and the second electrical signal, process the first electrical signal and the second electrical signal, and output a noise canceled signal.

Description

Docket No. 063758-5173 -WOTITLE

[0001] Noise-Cancelling MicrophoneCROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 690,120 filed September 3, 2024 titled “Noise Cancelling Microphone,” which is incorporated by reference herein in its entirety.TECHNICAL FIELD

[0003] The present disclosure generally relates to a noise-cancelling microphone or circuit, and in some embodiments, a headset having at least one noise-cancelling microphone / circuit.SUMMARY

[0004] In one embodiment, there is a noise-cancelling circuit including a first micro-electro- mechanical systems (MEMs) microphone coupled to a first surface of a printed circuit board (PCB), a second MEMs microphone coupled to a second surface of the PCB opposite the first surface, and an audio signal processor electrically coupled to the first MEMs microphone and the second MEMs microphone. The noise-cancelling microphone may further include a microphone housing, which further includes the PCB coupled to a first portion of the microphone housing.

[0005] The first MEMs microphone may be configured to receive a first set of one or more sound waves approaching the noise-cancelling microphone and output a first electrical signal. The second MEMs microphone may be configured to receive a second set of one or more sound waves and output a second electrical signal. The first MEMs microphone receives the first set of one or more sound waves from a first direction via a first aperture and the second MEMs microphone receives the second set of one or more sound waves from a second direction opposite the first direction via a second aperture. The first aperture opens outwardly in the first direction and the second aperture opens outwardly in the second direction opposite the first direction. The audio signal processor may be configured to receive the first electrical signal and the second electrical signal, process the first electrical signal and the second electrical signal, and output a noise-cancelled signal.

[0006] In some embodiments, the first MEMs microphone and the second MEMs microphone each include a MEMs sensor and an operational amplifier (op amp). The MEMs sensor may be configured to receive one or more sound waves and produce an electrical signal. The MEMs sensor may include a diaphragm suspended above a backplate, where the diaphragm oscillates with respectto the backplate, in response to receiving the one or more sound waves, creating a capacitance charge and a voltage difference. The op amp may be configured to receive the electrical signal and amplify the electrical signal to output an amplified electrical signal.

[0007] In some embodiments, the audio signal processor includes a third op amp electrically coupled to the first MEMs microphone and the second MEMs microphone. The third op amp may be configured to receive the amplified electrical signals from the first MEMs microphone and the second MEMs microphone and output the noise-cancelled signal.

[0008] In another embodiment, the audio signal processor includes a first operational amplifier (op amp) coupled to the first surface, a second op amp coupled to the second surface, and a third op amp electrically coupled to the first op amp and the second op amp. The first op amp may be electrically coupled to the first MEMs microphone and configured to receive the first electrical signal and output a first amplified electrical signal. The second op amp may be electrically coupled to the second MEMs microphone and configured to amplify the second electrical signal and output a second amplified electrical signal. The third op amp may be configured to receive the first amplified electrical signal and the second amplified electrical signal and output a noise-cancelled signal.

[0009] In some embodiments, the audio signal processor further includes an analog to digital converter (ADC) and a digital signal processor (DSP). The ADC may be configured to receive the first electrical signal and the second electric signal and convert the first electrical signal and the second electric signal into a digital signal. The DSP may be configured to receive the digital signal, process the digital signal, and output the noise-cancelled signal.

[0010] In yet another embodiment, there is a headset including a head-wearable structure, a first end of a boom coupled to the head-wearable structure, a second end of the boom, opposite the first end, coupled to a microphone housing, and a PCB coupled to the microphone housing comprising a noise-cancelling circuit. The noise-cancelling circuit may include a first MEMs microphone coupled to a first surface of the PCB, a second MEMs microphone coupled to a second surface of the PCB opposite the first surface, and an audio signal processor electrically coupled to the first MEMs microphone and the second MEMs microphone.

[0011] The first MEMs microphone may be configured to receive a first set of one or more sound waves approaching the noise-cancelling microphone and output a first electrical signal. The second MEMs microphone may be configured to receive a second set of one or more sound waves and output a second electrical signal. The first MEMs microphone receives the first set of one or more sound waves from a first direction via a first aperture and the second MEMs microphone receives the second set of one or more sound waves from a second direction opposite the first direction via a secondaperture. The first aperture opens outwardly in the first direction and the second aperture opens outwardly in the second direction opposite the first direction. The audio signal processor may be configured to receive the first electrical signal and the second electrical signal, process the first electrical signal and the second electrical signal, and output a noise-cancelled signal.

[0012] In some embodiments, the audio signal processor includes a first operational amplifier (op amp) coupled to the first surface, a second op amp coupled to the second surface, and third op amp electrically coupled to the first op amp and the second op amp. The first op amp may be electrically coupled to the first MEMs microphone and configured to receive the first electrical signal and output a first amplified electrical signal. The second op amp may be electrically coupled to the second MEMs microphone and configured to amplify the second electrical signal and output a second amplified electrical signal. The third op amp may be configured to receive the first amplified electrical signal and the second amplified electrical signal and output a noise-cancelled signal.

[0013] In another embodiment, the audio signal processor further includes an analog to digital converter (ADC) and a digital signal processor (DSP). The ADC may be configured to receive the first electrical signal and the second electric signal and convert the first electrical signal and the second electric signal into a digital signal. The DSP may be configured to receive the digital signal, process the digital signal, and output the noise-cancelled signal.BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The following detailed description of embodiments of the noise-cancelling microphone will be better understood when read in conjunction with the appended drawings of exemplary embodiments. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. For example, although not expressly stated herein, features of one or more various disclosed embodiments may be incorporated into other of the disclosed embodiments.

[0015] In the drawings:

[0016] Fig. 1 is a noise-cancelling headset having a noise-cancelling microphone, in accordance with an exemplary embodiment of the present invention, shown coupled to a helmet;

[0017] Fig. 2 is an example of the noise-cancelling headset of Fig. 1, shown coupled to a headband;

[0018] Fig. 3 is an example of a noise-cancelling circuit of the noise-cancelling microphone of Fig i;

[0019] Fig. 4 is another example of a noise-cancelling circuit of the noise-cancelling microphone of Fig. 1; and

[0020] Fig. 5A is a top view of the printed circuit board enclosed in the noise-cancelling microphone of Fig. 1;

[0021] Fig. 5B is a side view of the printed circuit board enclosed in the noise-cancelling microphone of Fig. 1;

[0022] Fig. 5C is a bottom view of the printed circuit board enclosed in the noise-cancelling microphone of Fig. 1; and

[0023] Fig. 6 is a cross-sectional view of the first micro-electro-mechanical systems utilized in the printed circuit board shown in Figs. 5A-5C.DETAILED DESCRIPTION

[0024] Referring to the drawings in detail, wherein like reference numerals indicate like elements throughout, there is shown in Figs. 1-6 a noise-cancelling microphone, generally designated 104, in accordance with an exemplary embodiment of the present invention. Noise-cancelling microphones are critical in numerous headset deployments, particularly for defense forces, emergency responders, and industrial personnel operating in high performance environments. For example, if a user wearing a headset in combat, in a helicopter, during firefighter rescue, etc., is attempting to speak into the microphone, filtering out the background noise such that the microphone picks up primarily what the user is saying is critical especially in extremely loud environments.

[0025] Referring to Figs. 1 and 2, the noise-cancelling microphone 104, as described in further detail below, includes a noise-cancelling circuit, generally designated 102, which utilizes at least two MEMs microphones in order to reduce or cancel out unwanted background noise. Utilizing multiple MEMs microphones inside of a microphone, configured to cancel out background noise while a user is speaking, allows the system to output a clean signal including the voice of the user. After receiving background noise and the user’s voice at the MEMs microphones, the signals can be processed using either a digital or analog solution to provide a clean noise-free signal. Thus, method and systems to produce a noise-free / reduced signal are disclosed herein.

[0026] Incorporating multiple MEMs microphones within a noise-cancelling circuit 102, specifically designed to suppress background noise during user speech, enables the system to generate a clear output signal that includes predominantly the user’s voice. Upon capturing both background noise and the user’s voice using MEMs microphones, the signals undergo processing via either digital or analog methods to deliver a noise-free or reduced-noise signal. Systems and methods for usingmultiple MEMs microphones for noise-cancelling and achieving improved signal quality are disclosed herein.

[0027] Fig. 1 illustrates a noise-cancelling microphone 104 incorporated in a headset (e.g., a communication device integrated within a padded earphone or ear cup 150), in accordance with an exemplary embodiment of the present invention. A portion of the headset may be coupled to a first end of the boom 140. The second end of the boom 140 opposite the first may be coupled to the noisecancelling microphone 104. In some embodiments, the noise-cancelling microphone 104 includes a housing configured to protect the noise-cancelling circuit 102 and is encased by a foam cover. As discussed below, the noise-cancelling microphone 104 may include the noise-cancelling circuit 102 that receives sound waves including background noise and a user’s voice and cancels out the noise leaving only the user’s voice, or at least reducing the background noise to make the user’s voice easier to hear. In some embodiments, the helmet 100 includes a mounting feature or rail 160. Some embodiments of rails contemplated for use with the present invention are described in International Patent Application No. PCT / US 18 / 22221 and U.S. Patent No. 7,849,517, the disclosure of each of which is hereby incorporated by reference in its entirety. One type of mounting rail contemplated for use are Ops-Core Accessor Rail Connectors (ARC Rails). The rail 160 may include a channel configured to receive a connector on the accessory coupling system.

[0028] Fig. 2 is an example of a noise-cancelling headset 200, in some embodiments. The earcup 250 may be a circumferential earcup. In the embodiment illustrated in Fig. 1, the earcup 250 is coupled to a mount arm that attaches to a helmet 100. As shown in Fig. 2, the earcup 250 may be coupled to a headband 280. In some embodiments, the earcup 250 is selectively attachable to both helmets 100 and headbands 280. The earcup 250 may include a cushion that is configured to contour the geometry of the user’s head and provide a better seal and proper attenuation. At least one of the earcups 250 may include a microphone (e.g., a noise-cancelling microphone). In one embodiment, the earcup 250 includes a boom arm 240 that may be flexible such that the user can bend the boom arm 240 and place the noise-cancelling microphone 204 a desired distance from the user’s mouth.

[0029] In another embodiment, the earcup 250 includes an additional control device or controller (not pictured) configured to control or adjust various aspects of the noise-cancelling microphone 204. For example, the controller may allow the user to mute or unmute the noise-cancelling microphone 204, activate or disable the noise-cancelling feature of the noise-cancelling microphone 204, and / or control the input sensitivity of the noise-cancelling microphone 204 by adjusting the input gain of the noise-cancelling microphone 204. In some embodiments, the controller includes a user interface to allow the user to interface with the controller. The user interface may include a button, a knob, asingle-pole switch, a push-button switch, a dimmer switch, a rocker switch, a momentary switch, a rotary switch, and / or a potentiometer mounted on an exterior surface of the earcup 250. The controller may also include control circuitry electrically coupled to the user interface and provided within a housing of the earcup 250. The control circuitry may control or adjust various aspects of the noisecancelling microphone 204 based on user input received by the user interface.

[0030] Fig. 3 is an example of a noise-cancelling circuit 102 configured to receive sound waves using at least two MEMs microphones (e.g., a first MEMs microphone 120 and a second MEMs microphone 124). The noise-cancelling circuit 102 may include the first MEMs microphone 120 configured to receive sound waves such as the first set of sound waves 110 and the second MEMs microphone 124 configured to receive sound waves such as the second set of sound waves 112. In some embodiments, the first and second set of sound waves 110 and 112 include one or more similar characteristics such as background noise, a user’s voice etc. For example, the first set of sound waves 110 includes sound waves from a user speaking and background noise and the second set of sound waves 112 includes sound waves from the background noise.

[0031] The first and second MEMs microphones 120 and 124 are analog MEMs microphones. An analog MEMs microphone comprises a flexibly suspended diaphragm above a fixed backplate such that when sound pressure (e.g., the first and / or second set of sound waves 110 and 112) passes through holes in the either the PCB and / or a sensor housing of the first and second MEMs microphones 120 and 124, the sound pressure causes the diaphragm to move proportionally to the sound waves’ amplitude. When the diaphragm moves, it creates a change in capacitance between the diaphragm and backplate creating a voltage difference (e.g., an electrical signal).

[0032] The noise-cancelling circuit 102 may further includes an audio signal processor 130. The audio signal processor 130 may include a first operational amplifier (op amp) 132, a second op amp 134, and a third op amp 136. In some embodiments, analog MEMs microphones include a preamplifier / buffer to amplify the electrical signals to a usable level (e.g., the first op amp 132, the second op amp 134, and / or another op amp integrated into the MEMs microphone component). Fig. 3 illustrates the first and second op amps 132 and 134 as differential buffers. In some embodiments, the first and second MEMs microphones 120 and 124 include an integrated op amp configured to amplify the signal output from the MEMs sensor portion of the component. Digital MEMs microphones may include an internal analog to digital converter (ADC) and an internal pre-amplifier such that the output signal is sent to a digital signal processor over a digital stream or interface.

[0033] Fig. 3 further illustrates the first MEMs microphone 120 receiving the first set of sound waves 110 and outputting a first electrical signal received by the first op amp 132. Similarly, thesecond MEMs microphone 124 receives the second set of sound waves 112 and outputs a second electrical signal received by the second op amp 134. In some embodiments, the first, second and third op amps respectively 132, 134, and 136 are differential op amps. The first, second and third op amps respectively 132, 134, and 136 amplify the difference between the two voltage inputs while suppressing any common voltage shared by both inputs. Thus, in some embodiments, the first electrical signal received by the first op amp 132 is amplified to be a first amplified electrical signal, and the second electrical signal received by the second op amp 134 is amplified to be a second amplified signal. The first amplified electrical signal and the second amplified signal are received by the third op amp 136. As mentioned before, any common voltages shared will be suppressed. For example, if the first amplified electrical signal includes the user’s voice and background noise and the second amplified electrical signal includes background noise, the output of the third op amp 136 will be a noise-cancelled signal 316 representative of the user’s voice. In some embodiments, the first and second op amps 132 and 134 are configured to perform signal conditioning or buffering and the third op amp 136 is configured to remove the common mode signal (e.g., the noise / background noise) and amplify the signal if needed.

[0034] Fig. 4 is another example of a noise-cancelling circuit. Circuit 302 illustrates another noise-cancelling circuit using at least two MEMs microphones and a digital solution to perform the noise-cancelling. The first and second digital MEMs microphones 320 and 324 may be digital and / or analog MEMs microphones. The MEMs microphone components (e.g., first and second digital MEMs microphones 320 and 324) illustrated in Fig. 4 may include a MEMs microphone sensor electrically coupled to an ADC. The first and second digital MEMs microphones 320 and 324 may be configured to receive the first and second set of sound waves 310 and 312 respectively (similar to Fig. 3) and convert them into an electrical signal. The respective ADC integrated in each MEMs microphone component (e.g., first and second digital MEMs microphones 320 and 324) may be configured to receive the respective electrical signal and convert it to a digital signal that can be read by an audio digital signal processor (DSP) 330. The audio DSP 330 may include a DSP core 332 and a component 334. In some embodiments, the DSP core 332 receives the first digital signal output by the first digital MEMs microphone and the second digital signal output by the second digital MEMs microphone. The DSP core 332 may be configured to modify one or more properties of the digital signal such as frequency response, provide noise-cancelling operations on each respective signal, etc. In some embodiments, the DSP core 332 performs the subtraction of the two microphone inputs (e.g., noise cancellation). Additionally, the DSP core 332 may perform equalization, background noise reduction and / or microphone calibration as required. Similar to the steps completed in Fig. 3, in someembodiments, the component 334 (e.g., a fourth op amp and / or a digital to analog converter) is configured to receive the first and second digital signal and suppress any common voltages shared, thus outputting the noise-cancelled signal 314. In some embodiments, the DSP performs the processing of the signal in the digital domain and component 334 is a digital to analog converter (DAC) configured to convert the digital signal into an analog signal. In some embodiments, component 334 is a programmable gain amplifier intended to gain or attenuate the signal and convert the signal to an analog output.

[0035] Figs. 5A-5C are assembly views of an example of the noise-cancelling circuit 102 enclosed in the microphone structure 104 shown in Figs. 1-2 and carrying the noise-cancelling circuits 102, 202 shown in Figs. 3-4. The assembly view includes a topside view, side view and bottom view of the noise-cancelling circuit 102. A vertical axis (A’) runs longitudinally through the center of the noisecancelling circuit 102 about the y-axis defining a central axis of the noise-cancelling circuit 102.

[0036] Fig. 5A shows the topside view of the noise-cancelling circuit 102 illustrating a first MEMs microphone 124 electrically coupled to the top portion of the printed circuit board (PCB) 106, a second aperture 126 coupled to a second MEMs microphone 124 on the opposite side of the PCB 106, and an audio signal processor 130 electrically coupled to the top portion of the printed circuit board (PCB) 106. Fig. 5C shows the bottom view of the noise-cancelling circuit 102 illustrating the second MEMs microphone 124 electrically coupled to the bottom portion of the PCB 106, opposite the top side, and a first aperture 122 coupled to the first MEMs microphone 120. The audio signal processor 130 may be electrically coupled to both the first MEMs microphone 120 and the second MEMs microphone 124 as described above with respect to Figs. 3 and 4. Fig. 5B shows the side view of the noisecancelling circuit 102 illustrating that the first MEMs microphone 120 and the second MEMs microphone 124 may be coupled to opposite sides of the PCB 106.

[0037] Fig. 5B further illustrates arrows 121 and 123 representing the general direction in which the first and second apertures 122 and 126 point or face respectively. The first aperture 122 faces generally towards the user’s mouth to capture sound waves produced by the user’s voice and common background noise. The second aperture 126 faces generally away from the user’s mouth to capture the common background noise. The direction in which the first and second apertures 122 and 126 point or face, as well as the arrangement and alignment of each MEMs microphone and their respective apertures along the central axis A’, allows the noise-cancelling microphone and circuitry to capture, process, and remove common background noise from the captured audio signal. In some embodiments, a baffle, a cone, a funnel, or a sloped wall may be provided around either or both of the first and second apertures 122 and 126 to capture the maximum amount of sound waves.

[0038] The first and second apertures 122 and 126 may open outwardly in opposite directions from one another, which allows the noise-cancelling microphone and circuitry to capture, process, and remove common background noise from the captured audio signal. In one embodiment, the first and second apertures 122 and 126 are provided on opposite sides of the PCB 106 as described above. In another embodiment, the first and second apertures 122 and 126 are provided on the housing of each of the first and second MEMs microphones 120 and 124, where the first and second MEMs microphones 120 and 124 are provided on opposite sides of the PCB 106 as described above. In another embodiment, where the first and second MEMs microphones 120 and 124 are provided on the same side of the PCB 106, the first aperture 122 may be provided on the housing of either the first MEMs microphone 120 or the second MEMs microphone 124. In the same embodiment, the second aperture 126 may be provided on the opposite side of the PCB 106 beneath the MEMs microphone that does not carry the first aperture 122 so that the first aperture 122 and the second aperture 126 are facing in opposite directions from one another.

[0039] In some embodiments, the bottom side of the PCB 106 and in turn the first aperture 122 of the first MEMs microphone 120 are coupled to the microphone structure such that the first aperture 122 is angled toward the mouth of a user and the top side of the PCB 106 including the second aperture 126 of the second MEMs microphone 124 is angled away from the mouth of the user. In some embodiments, positioning the first aperture 122 towards a user’s mouth allows the first MEMs microphone 120 to capture the maximum amount of sound waves produced by a user when speaking into the microphone structure. In some embodiments, positioning the second aperture 126 away from the user’s mouth allows the second MEMs microphone 124 to capture the maximum amount of sound waves produced by the background such that the common background noise captured by both the first and second MEMs microphones 124 and 124 can be cancelled.

[0040] As shown in Figs. 5A-5C, the first MEMs microphone 120, second MEMs microphone 124, and their respective apertures 122 and 126 may be axially aligned and longitudinally offset from one another along the central axis A’ by a pre-determined offset distance. The longitudinal offset may provide sufficient spatial separation between the first and second MEMs microphones 120 and 124, as well as their respective apertures 122 and 126, such that both MEMs microphones 120 and 124 capture common background noise, which is then removed from the captured audio signal during audio signal processing as described above. In some embodiments, the first and second MEMs microphones 120 and 124, as well as their respective apertures 122 and 126, may be laterally offset from one another with respect to the central axis A’. In some embodiments, the offset distance is equal to a width of the MEMs microphone sensor. In some embodiments, the offset distance may beoptimized to ensure maximum signal-to-noise (SNR) produced by the noise-cancelling microphone with respect to capturing and digitally reproducing the user’s voice.

[0041] Fig. 6 illustrates a cross-sectional view of the MEMs microphone 120 as described above in Figs. 1-5C. The first MEMs microphone 120 may include a housing 140, a MEMs sensor 142, an amplifier 146, the first aperture 122, the PCB 106, and a porous membrane 148. The MEMS sensor 142 and the amplifier 146 may be electrically coupled to one another via the PCB 106 and are housed within the housing 140. The MEMs sensor 142 may be electrically coupled to an input pin of the amplifier 146 via the PCB 106. The first MEMs microphone 120 may be electrically coupled to the audio signal processor 130, as shown in Figs. 5A-5C, via an output pin of the amplifier 146.

[0042] In some embodiments, the first aperture 122 is open outwardly providing fluid communication between a diaphragm 144 of the MEMs sensor 142 and sound waves propagating towards the first MEMs microphone 120. In some embodiments, the first aperture 122 is provided in the PCB 106. In another embodiment, the first aperture 122 is provided on the housing 140. The porous membrane 148 may cover the first aperture 122 allowing gases to permeate the porous membrane 148, while preventing liquids / water from permeating the porous membrane 148. In some embodiments, the porous membrane 148 is an expanded polytetrafluoroethylene (ePTFE) microporous membrane. In some embodiments, the porous membrane 148 covers the PCB 106 such that the first aperture 122 is covered by the porous membrane 148 when the first aperture 122 is provided in the PCB 106. In another embodiment, the porous membrane 148 covers the housing 140 such that the first aperture 122 is covered by the porous membrane 148 when the first aperture 122 is provided on the housing 140.

[0043] In one embodiment, the microphone 104 is coupled to one or more computers having one or more processors and memory (e.g., one or more nonvolatile storage devices). In some embodiments, memory or a computer-readable storage medium of memory stores programs, modules and data structures, or a subset thereof for a processor to control and run the various systems and methods disclosed herein. In one embodiment, a non-transitory computer-readable storage medium having stored thereon computer-executable instructions will, when executed by a processor, perform one or more of the methods disclosed herein.

[0044] It will be appreciated by those skilled in the art that changes could be made to the exemplary embodiments shown and described above without departing from the broad inventive concepts thereof. It is to be understood that the embodiments and claims disclosed herein are not limited in their application to the details of construction and arrangement of the components set forth in the description and illustrated in the drawings. Rather, the description and the drawings provideexamples of the embodiments envisioned. The embodiments and claims disclosed herein are further capable of other embodiments and of being practiced and carried out in various ways.

[0045] Specific features of the exemplary embodiments may or may not be part of the claimed invention and various features of the disclosed embodiments may be combined. Unless specifically set forth herein, the terms “a,” “an” and “the” are not limited to one element but instead should be read as meaning “at least one.” Finally, unless specifically set forth herein, a disclosed or claimed method should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the steps may be performed in any practical order.

Claims

CLAIMSWhat is claimed is:

1. A noise-cancelling circuit comprising: a first micro-electro-mechanical systems (MEMs) microphone coupled to a first surface, wherein the first MEMs microphone is configured to receive a first set of one or more sound waves and output a first electrical signal; a second MEMs microphone coupled to a second surface opposite the first surface, wherein the second MEMs microphone is configured to receive a second set of one or more sound waves and output a second electrical signal; and an audio signal processor electrically coupled to the first MEMs microphone and the second MEMs microphone, wherein the audio signal processor is configured to receive the first electrical signal and the second electrical signal, process the first electrical signal and the second electrical signal, and output a noise-cancelled signal.

2. The noise-cancelling circuit of claim 1, wherein the first MEMs microphone and the second MEMs microphone each comprise a MEMs sensor and an operational amplifier (op amp).

3. The noise-cancelling circuit of claim 2, wherein the MEMs sensor is configured to receive one or more sound waves and produce an electrical signal.

4. The noise-cancelling circuit of claim 3, wherein the op amp is configured to receive the electrical signal and amplify the electrical signal to output an amplified electrical signal.

5. The noise-cancelling circuit of claim 3, wherein the MEMs sensor includes a diaphragm suspended above a backplate, wherein in response to receiving the one or more sound waves, the diaphragm oscillates with respect to the backplate creating a capacitance charge and a voltage difference.

6. The noise-cancelling circuit of claim 5, wherein the audio signal processor comprises a third op amp electrically coupled to the first MEMs microphone and the second MEMs microphone, wherein the third op amp is configured to receive the amplified electrical signals from the first MEMs microphone and the second MEMs microphone and output the noise-cancelled signal.

7. The noise-cancelling circuit of claim 1 further comprising a printed circuit board (PCB), wherein the PCB comprises the first surface and the second surface is opposite the first surface.

8. The noise-cancelling circuit of claim 1, wherein the audio signal processor comprises: a first operational amplifier (op amp) coupled to the first surface, the first op amp being electrically coupled to the first MEMs microphone and configured to receive the first electrical signal and output a first amplified electrical signal; a second op amp coupled to the second surface, the second op amp being electrically coupled to the second MEMs microphone and configured to amplify the second electrical signal and output a second amplified electrical signal; and a third op amp electrically coupled to the first op amp and the second op amp, the third op amp being configured to receive the first amplified electrical signal and the second amplified electrical signal and output a noise-cancelled signal.

9. The noise-cancelling circuit of claim 1, wherein the audio signal processor further comprises: an analog to digital converter (ADC) configured to receive the first electrical signal and the second electric signal and convert the first electrical signal and the second electric signal into a digital signal; and a digital signal processor configured to receive the digital signal, process the digital signal, and output the noise-cancelled signal.

10. The noise-cancelling circuit of claim 1 , wherein: the first MEMs microphone receives the first set of one or more sound waves from a first direction via a first aperture in the second surface; and the second MEMs microphone receives the second set of one or more sound waves from a second direction opposite the first direction via a second aperture in the first surface, wherein the first aperture opens outwardly in the first direction and the second aperture opens outwardly in the second direction opposite the first direction.

11. A noise-cancelling microphone comprising: a microphone housing comprising: a printed circuit board (PCB) coupled to a first portion of the microphone housing, including a first side of the PCB and a second side of the PCB opposite the first side of the PCB, wherein:the first side of the PCB comprises (i) a first micro-electro-mechanical systems (MEMs) microphone configured to receive a first set of one or more sound waves and output a first electrical signal and (ii) a first operational amplifier (op amp), electrically coupled to the first MEMs microphone, configured to receive the first electrical signal and output a first amplified electrical signal, the second side of the PCB comprises (i) a second MEMs microphone configured to receive a second set of one or more sound waves and output a second electrical signal and (ii) a second op amp, electrically coupled to the second MEMs microphone, configured to amplify the second electrical signal and output a second amplified electrical signal, and the PCB includes a third op amp, electrically coupled to the first op amp and the second op amp, configured to receive the first amplified electrical signal and the second amplified electrical signal and output a noise-cancelled signal.

12. The noise-cancelling microphone of claim 11, wherein the first MEMs microphone and the second MEMs microphone each comprise a MEMs sensor.

13. The noise-cancelling microphone of claim 12, wherein the MEMs sensor is configured to receive one or more sound waves and produce an electrical signal.

14. The noise-cancelling microphone of claim 13, wherein the MEMs sensor includes a diaphragm suspended above a backplate, wherein in response to receiving the one or more sound waves, the diaphragm oscillates with respect to the backplate creating a capacitance charge and a voltage difference.

15. The noise-cancelling microphone of claim 11, further comprising: an analog to digital converter (ADC) configured to receive the first electrical signal and the second electric signal and convert the first electrical signal and the second electric signal into a digital signal; and a digital signal processor (DSP) configured to receive the digital signal, process the digital signal, and output the noise-cancelled signal.

16. The noise-cancelling microphone of claim 11, wherein: the first MEMs microphone receives the first set of one or more sound waves from a first direction via a first aperture in the second surface; andthe second MEMs microphone receives the second set of one or more sound waves from a second direction opposite the first direction via a second aperture in the first surface, wherein the first aperture opens outwardly in the first direction and the second aperture opens outwardly in the second direction opposite the first direction.

17. A headset comprising: a head-wearable structure; a first end of a boom coupled to the head-wearable structure; a second end of the boom, opposite the first end, coupled to a microphone housing; and a printed circuit board (PCB) coupled to the microphone housing comprising a noisecancelling circuit, wherein the noise-cancelling circuit comprises: a first micro-electro-mechanical systems (MEMs) microphone coupled to a first surface of the PCB, wherein the first MEMs microphone is configured to receive a first set of one or more sound waves and output a first electrical signal; a second MEMs microphone coupled to a second surface of the PCB opposite the first surface, wherein the second MEMs microphone is configured to receive a second set of one or more sound waves and output a second electrical signal; and an audio signal processor electrically coupled to the first MEMs microphone and the second MEMs microphone, wherein the audio signal processor is configured to receive the first electrical signal and the second electrical signal, process the first electrical signal and the second electrical signal, and output a noise-cancelled signal.

18. The headset of claim 17, wherein the audio signal processor comprises: a first operational amplifier (op amp) coupled to the first surface, the first op amp being electrically coupled to the first MEMs microphone and configured to receive the first electrical signal and output a first amplified electrical signal; a second op amp coupled to the second surface, the second op amp being electrically coupled to the second MEMs microphone and configured to amplify the second electrical signal and output a second amplified electrical signal; and a third op amp electrically coupled to the first op amp and the second op amp, the third op amp being configured to receive the first amplified electrical signal and the second amplified electrical signal and output a noise-cancelled signal.

19. The headset of claim 17, wherein the audio signal processor further comprises:an analog to digital converter (ADC) configured to receive the first electrical signal and the second electric signal and convert the first electrical signal and the second electric signal into a digital signal; and a digital signal processor configured to receive the digital signal, process the digital signal, and output the noise-cancelled signal.

20. The headset of claim 17, wherein: the first MEMs microphone receives the first set of one or more sound waves from a first direction via a first aperture in the second surface; and the second MEMs microphone receives the second set of one or more sound waves from a second direction opposite the first direction via a second aperture in the first surface, wherein the first aperture opens outwardly in the first direction and the second aperture opens outwardly in the second direction opposite the first direction.

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