Power-adaptive active noise reduction (ANR) headset

Abstract

Various embodiments include active noise reduction (ANR) headsets and methods for controlling such headsets. In some implementations, the headset includes at least one electroacoustic transducer, a power supply for powering at least one electroacoustic transducer, and a control circuit configured to apply active noise reduction (ANR) to ambient noise using at least one electroacoustic transducer, sample a voltage drop from the power supply, and adjust a compressor threshold for the ANR based on the sampled voltage drop from the power supply.

Description

Technical Field

[0001] (Claim of Priority) This application claims the priority of U.S. Patent Application No. 18 / 122,855, filed on March 17, 2023, the entire content of which is incorporated herein by reference.

[0002] (Field of the Invention) The present disclosure generally relates to wearable audio devices such as headsets. More particularly, the present disclosure relates to power adaptive active noise reduction (ANR) headsets and related methods for controlling such headsets.

Background Art

[0003] Compared to headsets (e.g., audio headsets) that provide only passive noise reduction (or attenuation), headsets that utilize an active noise reduction (ANR) system can significantly improve user comfort and communication. However, the ANR system and related acoustic components can consume a significant portion of the power used to operate such headsets.

Summary of the Invention

Means for Solving the Problems

[0004] All examples and features mentioned below can be combined in any technically possible way.

[0005] Various implementations of the present disclosure include active noise reduction (ANR) headsets and methods for controlling such headsets.

[0006] In some particular embodiments, the headset includes: at least one electroacoustic transducer configured to provide an audio output; a power supply for supplying power to at least one electrovolume transducer; and a control circuit configured to apply active noise reduction (ANR) to ambient (e.g., earcup residual) noise using at least one electroacoustic transducer; sample a voltage drop of the power supply; and adjust a compressor threshold for the ANR based on the sampled voltage drop of the power supply.

[0007] In additional specific embodiments, a method for controlling an active noise reduction (ANR) headset includes: applying the ANR to ambient noise (e.g., earcup residual) using the headset; sampling the voltage drop of the headset's power supply; and adjusting a compressor threshold for the ANR based on the sampled voltage drop of the power supply.

[0008] The implementation may include one of the following characteristics, or any combination thereof.

[0009] In one embodiment, the power source includes one or more batteries.

[0010] In certain cases, one or more batteries are selected from a group of different batteries having different chemical properties. In some examples, batteries have different chemical properties such as alkaline chemical properties, lithium chemical properties, and / or nickel-cadmium (NiCad) chemical properties.

[0011] In some implementations, the voltage drop of one battery is different from the voltage drop of a second battery. In some examples, the difference in voltage drop between two separate batteries is, at least in part, due to differences in the chemical properties of the two separate batteries.

[0012] In some cases, the power supply includes an external power supply.

[0013] In certain implementations, the external power supply includes a wired connection to the aircraft's power supply.

[0014] In some cases, adjusting the compressor threshold can improve the ANR performance of a headset.

[0015] In some implementations, improved ANR performance is characterized by at least one of the following: greater noise reduction in the audio output, or increased gain in the audio output.

[0016] In certain embodiments, adjusting the compressor threshold increases the battery life of a headset. In some examples, adjusting the compressor threshold helps extend battery life when encountering mechanical disturbances. In certain examples, mechanical disturbances may include head movements by the user (e.g., a pilot) and / or significant changes in ambient noise (e.g., in an aircraft).

[0017] In some cases, adjusting the compressor threshold is done automatically in response to the sampled voltage drop deviating from the voltage drop threshold.

[0018] In one embodiment, the compressor threshold is adjusted without user input commands.

[0019] In certain implementations, the control circuit is configured to repeatedly sample the voltage drop and dynamically adjust the compressor threshold in response to the sampled voltage drop deviating from the voltage drop threshold.

[0020] In some embodiments, the iterative method includes at least one of continuous sampling or periodic sampling. In some examples, continuous sampling is performed at defined intervals and / or dynamic intervals.

[0021] In some implementations, adjusting the compressor threshold involves reducing the compressor threshold to decrease power consumption by the headset. In one example, reducing the compressor threshold reduces power consumption by one or more components in the headset, including transducers, compressor circuits, and / or ANR circuits.

[0022] In certain cases, sampling voltage drop involves determining at least one of the following characteristics of the power supply, power supply impedance, charge or discharge state, battery quality, battery chemistry, connection quality, or voltage level over time.

[0023] In one embodiment, the headset further includes an interface that allows the user to input at least one characteristic of the power supply, and a control circuit is configured to adjust a compressor threshold based on at least one characteristic of the power supply. In some examples, the interface allows the user to input at least one of the following: battery type, battery serial number, battery brand, or battery size. In further examples, the interface allows the user to scan a quick response (QR) code associated with the battery and / or provide a photograph of the battery.

[0024] In some implementations, the headset further includes a feedforward microphone input and a feedback microphone input, and the control circuit includes an ANR engine and a compressor, the compressor being configured to compress the feedback loop gain from the feedback microphone input according to a compressor threshold before the input in the ANR engine.

[0025] In certain embodiments, the compressor threshold is determined using a compressor threshold control loop that has a power supply voltage drop as an input and a compressor threshold adjustment as an output.

[0026] In some cases, the control circuit is further configured to adjust the power monitoring system based on the sampled voltage drop. In some examples, the power monitoring system updates the battery level, remaining battery life indicator, or remaining battery time indicator based on the sampled voltage drop.

[0027] In some aspects, sampling the voltage drop of the power supply includes transmitting a set of test signals to the power supply and measuring a voltage response for each of the set of test signals.

[0028] In one implementation, the aviation audio device includes a headset.

[0029] In certain aspects, adjusting the compressor threshold helps to comply with aviation-specific communication protocols. In some examples, adjusting the compressor threshold helps to comply with protocols related to communication disconnection or disconnection, Bluetooth (Bluetooth, BT) reset, communication interference, and / or total harmonic distortion (THD) specifications. In certain cases, adjusting the compressor threshold helps to comply with aviation-specific communication protocols (e.g., Federal Aviation Administration protocols) that require less than 10% THD.

[0030] Two or more features described in this disclosure, including the features described in the summary section of the present invention, may be combined to form implementations not specifically described herein.

[0031] Details of one or more implementations are described in the accompanying drawings and the following description. Other features, objectives, and advantages will become apparent from this description, the drawings, and from the claims.

Brief Description of the Drawings

[0032] [Figure 1] It is a schematic diagram of an audio device according to various implementations. [Figure 2] This is a schematic diagram of other audio devices in various implementation forms. [Figure 3] This is a schematic diagram of other audio devices in various implementation forms. [Figure 4] This is a schematic diagram of the electronic components included in audio devices, presented in various implementation forms. [Figure 5] This is a schematic diagram of active noise reduction (ANR) circuits for audio devices in various implementation configurations. [Figure 6] This flowchart illustrates the process of adjusting the ANR (Automatic Network Rating) of audio devices in various implementation configurations.

[0033] Please note that the drawings of various implementation configurations are not necessarily to scale. The drawings are intended to show only typical embodiments of this disclosure and should not be considered to limit the scope of the invention. In the drawings, similar numbering indicates similar elements between drawings. [Modes for carrying out the invention]

[0034] As described herein, various aspects of this disclosure relate, in general, to active noise reduction (ANR) headsets with power adaptive capability. In certain cases, the headset (e.g., an audio headset) is configured to adjust the ANR configuration based on the detected characteristics of the headset power supply. In more specific cases, the audio headset is configured to adjust the compressor threshold for the ANR based on the sampled voltage drop of the headset power supply.

[0035] Parts commonly labeled in the diagram are considered substantially equivalent for illustrative purposes, and redundant descriptions of those parts are omitted for clarity.

[0036] As described herein, ANR systems and associated acoustic components can consume a significant portion of the headset's power resources. In some conventional cases, low charge conditions, battery chemistry, and / or low-quality power supplies can cause an increase in internal power impedance, leading to an increase in power supply voltage drop, such as that induced by load current. This can degrade the ANR performance in headsets that rely on such power supplies. In further conventional cases, ANR systems are designed for worst-case power supply scenarios, e.g., high power impedance and / or low charge conditions. These conventional ANR systems are not adaptable to distinct power supply characteristics and therefore may not fully utilize the headset's performance capabilities (e.g., when a higher-quality power supply is available).

[0037] In contrast to these conventional systems, various implementations include a headset that includes a control circuit configured to apply ANR to ambient noise (or earcup residual noise), sample the voltage drop of the power supply (for the headset), and adjust a compressor threshold for the ANR based on the sampled voltage drop of the power supply. In specific cases, the power supply includes one or more batteries, and the headset is configured to detect separate voltage drops across separate batteries and adjust a compressor threshold(s) for the ANR based on those separate voltage drops.

[0038] The embodiments and implementations disclosed herein may be applicable to a wide variety of wearable audio devices. In some cases, wearable audio devices can take various forms, such as headphones (whether on-ear or off-ear), headsets, watches, glasses, audio accessories or clothing (e.g., audio hats, audio visors, audio jewelry), helmets (e.g., for military, industrial, or motorcycle applications), neck-mounted speakers, shoulder-mounted speakers, and body-mounted speakers. Some of the disclosed embodiments may be particularly applicable to personal (wearable) audio devices such as over-ear headphones, on-ear headphones, in-ear headphones (also called earphones), audio glasses, or other head-mounted audio devices. While wearable audio devices are primarily described herein in the context of headsets (e.g., over-ear or in-ear), this disclosure is not intended to be limited thereto unless expressly provided otherwise.

[0039] Wearable audio devices, as described according to various implementation forms, may include features found in one or more other wearable electronic devices, such as smart glasses and smartwatches. These wearable audio devices may include additional hardware components, such as one or more cameras, location tracking devices, and microphones, which may enable voice recognition, visual recognition, and other smart device functions. The descriptions of wearable audio devices included herein are not intended to exclude these additional capabilities in such devices.

[0040] The wearable audio devices described herein can be used in a variety of different applications, including aerospace, space, military (e.g., use in vehicles and / or non-mounted applications), broadcasting, coaching (e.g., sports / athletic competitions such as football games), games, industry (e.g., manufacturing, warehousing), construction, conferences, vehicle-based transport services (e.g., delivery by truck or van), motor racing, motorcycles or motorbikes, professional audio (e.g., studio production, audio mixing, live performances), and general lifestyle applications (e.g., consumer electronics wearable audio devices such as headphones or earphones), as well as other applications that can be understood based on this disclosure. Furthermore, a single wearable audio device (e.g., a single headset) can be used in multiple different applications, as the audio device control platform allows for customization of the audio device to optimize its suitability for different applications. In some implementations, the customization of the audio device control platform is performed automatically based on one or more accessories connected to the audio device. The audio device can be customized by using other triggers, either alternatively or additionally, with the use of a connected control module (e.g., an inline control module and / or a mobile device application), based on user input, environmental conditions (e.g., ambient noise level), sensor input (e.g., atmospheric pressure), or other triggers as revealed in light of this disclosure.

[0041] Some exemplary implementations relate to audio devices, including aviation headsets. Aviation headsets are used by pilots in both general and commercial aviation. Such headsets may be connected, for example, to air traffic control (ATC) and to aircraft communication systems for communicating with other pilots. The headset can also be used as a public addressing system, for example, for pilots to communicate with passengers on board the aircraft. Aircraft communication systems typically include analog communication systems, such as internal communication devices. In some cases, such internal communication device systems may be configured to communicate over very high-frequency (VHF) bands (e.g., 18 MHz to 136.975 MHz) where each channel is separated from adjacent channels by a predetermined bandwidth (e.g., 8.33 kHz in Europe, 25 kHz in other regions). Analog modulation techniques such as amplitude modulation (AM) may be used for communication, and conversations may be conducted in simplex mode. In some cases, such as transoceanic flights, other frequency bands, such as the high-frequency (HF) band, can be used for satellite communications. Aviation headsets can be used, for example, by pilots and air traffic controllers to communicate with each other. Even within the context of aviation use, headsets may be optimized based on the class or specific aircraft being used. For example, the type may include, for example, propeller aircraft, jet passenger aircraft, or helicopters, while specific aircraft may include, for example, the Boeing 737, Boeing 777, Airbus A320, or McDonnell Douglas DC-9.

[0042] Figure 1 shows an example of a wearable audio device 10, including an aviation headset 100. In certain cases, the headset 100 includes a frame having at least one earpiece (e.g., earcup) 105 on each side, the earpiece fitting over, around, or covering the user's ear. In some cases, the frame is optional so that the earpiece 105 is connected to or wirelessly connected to other components within the wearable audio device 10. Each earcup 105 houses an acoustic transducer or speaker. The headset 100 also includes a headband (e.g., an over-the-head bridge) 110 for connecting two earpieces (e.g., earcups) 105. In various implementations, the headset 100 is configured to position at least one, and in some cases both, earpieces 105 in close proximity to the user's ear. For example, the headset 100 (and other headset forms of the audio device 10 described herein) may be configured to position the earpiece(s) 105 in close proximity to the user's ear when worn by the user. In some cases, this proximity includes positioning the earpiece(s) 105 on or over the ear (e.g., using an earcup), positioning it inside the ear (e.g., using an earbud), or placing it on top of the ear (e.g., using an ear hook). In some cases, the proximity positioning may result in the user's ear being completely, partially, or not at all covered.

[0043] In some implementations, an electronic component (e.g., a microphone such as a boom microphone) 115 can be physically connected to one of the earcups 105. The headset 100 can be connected to the aircraft's internal communication system using a connection cable 120 and may also include a control module 125 containing one or more control units for the headset 100. In some cases, analog signals to and from the aircraft's internal communication system are transmitted through a wired connection provided by the connection cable 120. In other or additional cases, the headset 100 may include electronic components 70 such as a control chip and / or circuitry, electroacoustic transducers, microphones and associated modules, power supply components such as batteries and / or connectors, and interface components such as capacitive touch interface components. In certain cases, the electronic components 70 include a controller coupled with an electroacoustic transducer, and the controller is also configured to connect to the electronic component (e.g., when locked with the audio device 10). In various implementations, the controller includes one or more processors and is configured to communicate with onboard memory and / or one or more remote storage devices.

[0044] It is further understood that the electronic device 70 may include other components not specifically shown in the accompanying drawings, such as communication components (e.g., wireless transceivers, WTs) configured to communicate with one or more other electronic devices connected via one or more wireless networks (e.g., local WiFi networks, Bluetooth connections, or radio frequency (RF) connections), as well as amplification components and signal processing components. The electronic device 70 may also include motion and / or position tracking components, such as inertial measurement units (IMUs) such as microelectromechanical system (MEMS) devices combining multi-axis accelerometers, gyroscopes, and / or magnetometers, and optical tracking systems.

[0045] While the example in Figure 1 shows an aviation headset including earcups for around the ears, aviation headsets with other form factors, including headsets having in-ear or on-ear headphones, are also compatible with the technology described herein. In examples including in-ear headphones, the overhead bridge may be omitted, and the boom microphone may be attached to the user via the headset or via a separate structure. Furthermore, the term headset as used herein includes various types of acoustic devices that may be used for aviation purposes, including, for example, earphones and earbuds. Additional headset features are disclosed, for example, in U.S. Patent Application No. 15 / 238,259 ("Communications Using Aviation Headset"), filed August 16, 2016, and U.S. Patent Application No. 16 / 953,272 ("Wearable Audio Device with Control Platform"), filed November 19, 2020, each of which is incorporated herein by reference in whole.

[0046] It is further understood that any component described as connected to or coupled to the audio device 10 or another component in another system disclosed according to the implementation may communicate using any conventional wired connection and / or additional communication protocol. In some cases, the communication protocol(s) may include Wi-Fi protocol, IEEE 802.11 b / g, cellular network protocol (e.g., third, fourth, or fifth generation (3G, 4G, 5G cellular networks)), or one of several Internet of Things (IoT) protocols such as Bluetooth, BLE Bluetooth, ZigBee (mesh LAN), Z-wave (sub-GHz mesh network), 6LoWPAN (lightweight IP protocol), LTE protocol, RFID, or ultrasonic audio protocol. In various specific implementations, components separately housed within the audio device 10 are configured to communicate using one or more conventional wireless transceivers.

[0047] It is understood that the wearable audio device 10 in various implementation forms can take on additional form factors. For example, Figure 2 shows the wearable audio device 10 in the form of a personal communication headset 10 (e.g., an aviation headset). Reference numerals followed by "A" or "B" indicate features corresponding to the right or left side of the audio device 10, respectively. The audio device 10 includes a headband having a curved portion 130 and a right end and a left end. The right housing 132A and the left housing 132B are positioned at the right and left ends of the headband, respectively. The curved portion 130 functions as an over-the-head bridge between the left and right housings 132. A spring band 134 (e.g., spring steel) extends from the right housing 132A through the curved portion 130 to the left housing 132B. The spring band 134 provides a clamping force to move the housings 132 toward each other (approximately along the horizontal plane passing through the wearer's head) while the headband is worn by the user. The left and right housings 132 can be moved a certain distance either upward toward the arched portion 130 or downward toward the arched portion 130 to accommodate smaller or larger heads, respectively.

[0048] The pads (right pad 136A or left pad 136B, generally 136) are attached to each housing 132 and are used to comfortably secure the headset 10 to the head. As used herein, “pad” means a compliant member that can be compressed and / or deformed under applied pressure and is configured to contact the user’s head in a manner that supports the headband. In some cases, when the audio device (headset) 10 is fitted to the head, each pad 136 extends from its anterior end over the ear to its posterior end lower on the head and behind the ear. In some cases, each pad 136 has a contoured surface 138 for contact with the user’s head. The boom 140 extends from a rotatable base 142 near the bottom of one of the housings (e.g., the right housing 132A as shown) and is used to position and support the microphone 144 attached to the other end. The boom 140 can be partially adjusted by rotating it around its base 142 to position the microphone 144 properly relative to the user’s mouth. The boom 140 may be permanently fixed to the housing 132A, or it may be detachable so that the audio device 10 can be used for both aviation and non-aviation applications (e.g., music playback). A connector 146 for a communication cable extends from the bottom of the right housing 132A. An earpiece (e.g., earphone) connector cable 148 extends from one end of each housing 132 and connects to an earpiece 150 such as an earphone or other type of in-ear headphones. Additional features of the audio device 10 shown in Figure 2 are described in U.S. Patent No. 10,187,718, which is incorporated herein by reference in its entirety.

[0049] Figure 3 shows another audio device 10, including around-ear headphones 310. The headphones 310 may include a pair of earpieces (e.g., earcups) 320 configured to cover or fit over the user's ears. A headband 330 is stretched between the pair of earpieces 320 and is configured to rest on the user's head (e.g., covering the top of the head or stretched around the head). In some implementations, the headband 330 may include a head cushion 340. Within one or both of the earpieces 320, depending on the implementation, are housed electronic components 70 and other components for controlling the headphones 310. The electronic components 70 may include one or more parts of electronic components, or connectors therefor, as described with respect to the audio device 10 herein. Many of the wearable audio devices described herein can take advantage of the features of various implementations, and it should be understood that the wearable audio device 10 shown and described with reference to Figures 1-3 is merely illustrative. In addition to the electronic equipment 70, various implementations of the audio device (or headset) 10 may include one or more accessory ports for accommodating (e.g., interface with or connect to) accessories such as a boom microphone, battery module, power connector, sensor module, communication module (e.g., a wireless module such as one for enabling Bluetooth or Wi-Fi, and / or a wired module), a self-powered communication module (e.g., a self-powered Bluetooth module), and / or a microphone module. In particular, the accessories may be coupled to one or more parts of the headset 10, for example, via an earpiece or earcup. Other connection configurations are also possible within various implementations. Additional details of an exemplary accessory connection for an earpiece 400 are contained in U.S. Patent Application No. 16 / 930,579, “Wearable Audio Device with Modular Component Attachment,” filed July 16, 2020, which is incorporated by reference in its entirety.

[0050] Figure 4 is a schematic diagram of an illustrative electronic device 70 of a headset 10 in various implementation configurations. As described herein, in some implementation configurations, one or more components within the electronic device 70 may be located in a separate device (e.g., a smart device such as a smartphone, tablet computer, control module, or electronic flight bag). In addition, one or more functions performed by components within the electronic device 70 may be performed in a separate device from the wearable audio device 10, or may be replicated in a separate device. In various specific implementation configurations, each earpiece in the headset includes a separate electronic device 70.

[0051] In any case, returning to Figure 4, the electronic device 70 may include at least one transducer 500 for providing audio output. The electronic device 70 may also include one or more sensors 510, such as a position-based sensor (e.g., a geolocation sensor), a motion-based sensor (e.g., an inertial measurement unit, or IMU), an optical sensor, or one or more microphones (e.g., a microphone array). The electronic device 70 may also include one or more communication devices 520, such as one or more transmitters and / or receivers (e.g., wireless and / or wired transmitters / receivers). In various implementations, the communication devices 520 may be configured for multiple communication protocols, such as Bluetooth, BLE, Zigbee, etc., as well as wireless and internal communication equipment communications. The electronic device 70 may also include an accessory port connector 530 for detecting connections (e.g., electrical and / or communication connections) with accessories (e.g., accessory 420). At least one power source 540 (e.g., one or more batteries, charging devices, and / or wired power sources) is shown together with an interface 550 (e.g., a user interface such as a touchscreen, capacitive touch interface, gesture detection interface, or voice command interface).

[0052] The transducer(s) 500, sensors 510, communication devices(s) 520, connectors 530, power supplies(s) 540, and / or interfaces 550 can be connected to a control circuit (or controller) 560, which in some cases includes one or more processors (PUs) for performing the functions described herein. The processor(s) are coupled with memory in various implementations. In some cases, the functions of a separate processor are performed in a separate controller 560 not shown. However, in other cases, the controller 560 may include one or more processors for performing functions, for example, by the execution of instructions stored in memory. In certain implementations, the controller 560 may include an ANR circuit 570 for controlling the active noise reduction (ANR) function in the headset 10. As described herein, the ANR circuit 570 may be configured to adjust the audio output in the transducer(s) 500 based on a detected voltage drop in the power supplies(s) 540.

[0053] Figure 5 is a schematic diagram of the ANR circuit 570 in various implementation configurations. The ANR circuit 570 includes an ANR engine (or ANR subsystem) 580 configured to control the audio output to transducer 500 (for example, by adjusting the gain on amplifier 590, such as a differential amplifier) ​​based on inputs from a feedback microphone 600, shown as a feedback loop 610, and inputs from a feedforward microphone 620 (after passing through a feedback filter 624), shown as a feedforward loop 630. A compressor threshold loop 640 is shown, and an ANR compressor (also called an ANR feedback attenuator) 650 is shown, configured to compress the feedback input to the ANR engine 580 by a compressor threshold 660.

[0054] Compression of the feedback loop input 610 is performed before the feedback loop input 610 enters the ANR engine 580 (or outside the ANR engine 580) because an uncompressed feedback signal (e.g., noise overload) could overload the electronics within the ANR engine 580. For example, an uncompressed feedback signal may have a wide dynamic range (e.g., resulting from noise and / or buffeting) that exceeds the maximum input value of the electronics in the circuits within the ANR engine 580.

[0055] In various implementations, the ANR compressor 650 is configured to compensate for noise overload to the ANR circuit 570, for example, due to sudden changes in ambient noise conditions and / or ambient noise exceeding a threshold. During operation, the ANR compressor 650 is configured to reduce the gain from the ANR feedback loop 610 in response to the detection of a noise overload event, the detection of a potential noise overload event, and / or the prediction of a noise overload event.

[0056] As shown in Figure 5, the ANR circuit 570 includes a compressor threshold loop 640 that allows adjustment of the compressor threshold 660 based on sampled voltage drops of the power supply 540. The compressor threshold 660 can control the amount of attenuation of the input signal from the feedback loop 610 before it enters the ANR engine 580. The compressor threshold loop 640 is configured to sample the voltage drops of the power supply 540 (e.g., periodically, scheduled, and / or repeatedly) and adjust the compressor threshold 660 based on those sampled voltage drops (e.g., in response to changes in voltage drops and / or deviations of the voltage drop(s) from the threshold). As shown in the process flow diagram of Figure 6, in various implementations, the ANR circuit 570 is configured to perform a process that includes (P1) applying active noise reduction (ANR) to ambient noise (or earcup residual noise) to provide an audio output in the transducer(s) 500, and (P2) sampling the voltage drops of the power supply 540. In decision (D3), the ANR circuit 570 compares the sampled voltage drop(s) to a voltage drop threshold(s). If the voltage drop(s) deviates from the threshold(s) (Yes in D3), in process (P4), the ANR circuit 570 adjusts the compressor threshold 660 of the ANR (e.g., ANR engine 580). If No in D3 (the voltage drop(s) does not deviate from the threshold(s)), the ANR circuit 570 continues to periodically and / or continuously sample the voltage drop of the power supply 540 (returning to process (P2)).

[0057] Continuing to refer to the exemplary ANR circuit 570 in Figure 5, the compressor threshold loop 640 includes a voltage detector 670 (e.g., a resistor) configured to detect the voltage drop of the power supply 540. In particular cases, in addition to, or instead of using, the voltage detector 670, sampling the voltage drop of the power supply 540 includes determining at least one of the following characteristics of the power supply 540: power supply impedance, charge or discharge state, battery quality, battery chemistry, connection quality, or voltage level over time.

[0058] In various implementations, the voltage drop can be measured by determining the voltage difference between the positive and negative terminals of a power supply 540 (e.g., a battery) under different loads. The correlation between the measured power supply current and voltage makes it possible to determine the impedance of the power supply 540 (e.g., a battery) and its charge state. This charge determination can also be achieved by instantaneously loading the power supply 540 with a predetermined load (resistor) and measuring the voltage across the terminals of the power supply 540. The voltage drop of the power supply (e.g., a battery), a known resistance value, and the measured power supply current make it possible to determine the power supply impedance and charge state of the power supply 540. Furthermore, an increasing power supply resistance of the power supply 540 (e.g., a battery) can indicate a change in the charge state of the power supply 540.

[0059] As used herein, power quality (within the range of identical chemical properties, such as the chemical properties of batteries) can vary among power supply manufacturers and typically correlate with cost. Proprietary chemical properties and manufacturing improvements from some manufacturers (in addition to basic chemical properties) can enable greater battery capacity and lower power impedance compared to other manufacturers. Higher power quality can enable greater current supply capacity and longer battery life.

[0060] In some embodiments, sampling the voltage drop across the power supply 540 includes sending a set of test signals to the power supply 540 and measuring the voltage response for each of the test signals. In certain cases, the voltage drop across the power supply 540 can be sampled using a sampling circuit 672, as shown in Figure 5 (as an optional choice). The sampling circuit 672 may include a fixed resistor 674 and a control switch 676 for sampling the voltage drop across the power supply. In certain cases, the fixed resistor 674 and the control switch 676 can be used to generate a predetermined load current from the power supply 540. The power supply impedance can be determined by analyzing the voltage across the power supply 540 and the voltage drop across the resistor 674. In some cases, the control switch 676 may be controlled by a controller 560, which may include, for example, one or more microcontrollers, via hardware and / or software functions.

[0061] As shown in the circuit example in Figure 5, the voltage drop amplifier (or power sensing amplifier) ​​680 amplifies the voltage drop signal detected by the voltage detector 670, and the amplified signal passes through a low-pass filter (LPF) 690. The output of the LPF 690 is added to the output from a separate section 640A of the compressor threshold loop 640. That section 640A of the compressor threshold loop 640 includes an amplifier 692 that amplifies a driver resistance signal comparing the output from the voltage regulator 694 with the output of the differential amplifier 590, a low-pass filter 696 that filters the amplified signal, and an envelope detector 700 that outputs the demodulated envelope of the signal from the low-pass filter 696. The outputs of the envelope detector 700 and the low-pass filter 690 from the other section 640 of the compressor threshold loop 640 are used to define the compressor threshold 660. In some cases, the outputs of the envelope detector 700 and the low-pass filter 690 are summed to define an adjustment to the compressor threshold 660.

[0062] As described herein, variations in power supply characteristics can affect headset performance, potentially resulting in reduced performance, overuse of power resources, and / or underuse of performance capabilities. The ANR circuit 570 illustrated and described herein is configured to improve headset performance, extend battery life, and so on, by dynamically adjusting a compressor threshold 660 based on the characteristics of the power supply 540. In some implementations, the power supply 540 includes one or more batteries. For example, the power supply 540 may include one or more replaceable, rechargeable, and / or disposable batteries. In certain cases, the one or more batteries are selected from a group of different batteries having different chemical properties. In some examples, the batteries have different chemical properties, such as alkaline chemical properties, lithium chemical properties, and / or nickel-cadmium (NiCad) chemical properties. In some implementations, the voltage drop of a first battery is different from the voltage drop of a second battery. In some examples, the difference in voltage drop between two separate batteries is at least partially due to the difference in the chemical properties of the two separate batteries.

[0063] In additional implementations, power supply 540 includes an external power supply. An exemplary external power supply may include a wired connection, such as a wired connection to the power supply of an aircraft or a military vehicle. In some cases, distinctions between the types and / or quality of the external power supply may be detectable by the ANR circuit 570, for example, using the separate associated voltage drops of those power supplies 540.

[0064] As described herein, in certain implementations, adjusting the compressor threshold 660 improves the ANR performance of the headset 10. For example, improved ANR performance can be characterized by a greater reduction in noise in the audio output to the transducer(s) 500 and / or an increase in gain in the audio output to the transducer(s) 500. In further implementations, adjusting the compressor threshold 660 increases the battery life of the headset 10 (e.g., of the battery-type power supply 540). In some examples, adjusting the compressor threshold 660 helps extend battery life when encountering mechanical disturbances. In certain examples, mechanical disturbances may include head movements by the user (e.g., a pilot) and / or significant changes in ambient noise (e.g., in an aircraft). For example, when headset 10 is used as an aviation and / or military headset, the user (e.g., a pilot) may frequently and / or suddenly change the direction of their head (or line of sight), which can affect the shielding seal of the headphones over the user's ears or ear area. Furthermore, significant changes in ambient noise are common in aviation and / or military applications. In conventional headsets, changes in shielding and / or significant fluctuations in ambient noise can cause overload events (e.g., clicking, voice distortion in communications, etc.) and strain the power supply. In contrast to conventional headsets, headset 10 is configured to respond effectively to changes in shielding and significant changes in ambient noise, for example, by conserving power resources when it is not beneficial and / or by improving noise cancellation performance when it is beneficial.

[0065] In some cases, as described with respect to the flowchart in Figure 6, the compressor threshold 660 is adjusted automatically in response to the sampled voltage drop deviating from the voltage drop threshold. For example, the voltage drop threshold can be equal to a value such as approximately 3 percent, 5 percent, 10 percent, 15 percent, 20 percent, or X volts. In various implementations, the ANR circuit 570 samples the voltage drop of the power supply 540 and automatically adjusts the compressor threshold 660 if the voltage drop deviates from the threshold (e.g., greater than Z percent or less than Y volts). That is, the ANR circuit 570 is configured to adjust the compressor threshold 660 without user input commands. In various implementations, the automatic adjustment of the compressor threshold 660 is based on one or more sampled voltage drops deviating from the voltage drop threshold (or multiple thresholds). In some implementations, the voltage drop threshold includes a range of values ​​or percentages. In further cases, the threshold is adjusted over time, for example, based on the recent history of sampled voltage values.

[0066] In certain cases, the ANR circuit 570 is configured to repeatedly sample the voltage drop and dynamically adjust the compressor threshold 660 in response to the sampled voltage drop deviating from the voltage drop threshold. In some embodiments, the repeated sampling includes continuous sampling and / or periodic sampling. In some examples, continuous sampling is performed at defined intervals and / or dynamic intervals. In some additional cases, the ANR circuit 570 samples the voltage drop(s) in response to a trigger. Various non-limiting triggers include detecting a change in accessory connection to the audio device 10, detecting a change in power supply 540 (e.g., between batteries, or between batteries and a wired power supply), detecting a change in the power state of the audio device 10 (e.g., power cycling, power on, sleep mode), detecting a change in ambient acoustic conditions (e.g., a significant change in ambient noise level), or a user interface command to start or change the operating mode of the audio device 10.

[0067] In some implementations, adjusting the compressor threshold 660 includes reducing the compressor threshold 660 to reduce power consumption by the headset 10. In one example, reducing the compressor threshold 660 reduces power consumption by one or more components in the headset, including the transducer 500, the compressor circuit 660, and / or the ANR circuit 570. Reducing the compressor threshold 660 can extend the lifespan of the power supply 540 in various implementations.

[0068] As described herein, the sampled voltage drop of the power supply 540 can be sampled by determining at least one of the following characteristics of the power supply 540: power supply impedance, charge or discharge state, battery quality, battery chemistry, connection quality, or voltage level over time. In some embodiments, interface 550 allows the user to input at least one characteristic of the power supply 540, and control circuit 560 is configured to adjust the compressor threshold based on the characteristics of the power supply 540. In some examples, interface 550 allows the user to input at least one of the following: battery type, battery serial number, battery brand, or battery size. In further examples, interface 550 allows the user to scan a quick response (QR) code associated with a battery and / or provide a photograph of the battery.

[0069] In additional implementations, the controller 560 (Figure 4) includes a power monitoring system (MS) 710 configured to monitor aspects of the power supply 540, such as the quality of the power connection, the remaining power available from the power supply 540 (e.g., if the power supply is a battery), etc. The power monitoring system 710 can provide real-time or near-real-time information about the power supply, for example, through one or more interfaces 550 (such as a visual display and / or audio output via a transducer 500) in the headset 10. In specific cases, the power monitoring system 710 updates a battery level, remaining battery life indicator, or remaining battery time indicator based on a sampled voltage drop of the power supply 540.

[0070] As described herein, various embodiments of the headset 10 may be useful in consumer applications, commercial aircraft applications, private aircraft applications, transportation, military applications, and the like. In some implementations, the headset 10 is part of an aviation audio device that is required to comply with aviation-specific communication protocols. In some examples, adjusting the compressor threshold 660 helps to comply with protocols related to communication disconnection or disconnection, Bluetooth (BT) reset, communication disturbance, and / or total harmonic distortion (THD) standards. In specific cases, adjusting the compressor threshold 660 helps to comply with aviation-specific communication protocols that require THD of 10 percent or less (e.g., Federal Aviation Administration protocols).

[0071] As described herein, various specific implementations allow a headset to adaptively assign a compressor threshold for the ANR system based on the characteristics of the headset power supply. In certain cases, the headset 10 is configured to operate with various power supplies, or different types of power supplies, such as different battery types including alkaline, lithium, and NiCad, and to adjust and match the compressor threshold accordingly. Some conventional headsets fix the compressor threshold based on assumptions about the characteristics of the power supply or predetermined characteristics of the power supply, for example, the assumption that the power supply is an alkaline battery of a certain quality. While the voltage discharge of an alkaline battery may generally be linear, the voltage discharge of a different battery type (e.g., lithium) may follow a different profile. Furthermore, power supply impedance, battery quality (high vs. low), charge state, and connection quality can all affect the output of the power supply (e.g., battery). As described herein, conventional headsets cannot account for the above variations in power supply characteristics (e.g., battery characteristics) and cannot adjust and match the compressor threshold accordingly. Various specific implementations can sample the voltage drop of the power supply periodically, continuously, or responsively (e.g., in response to a trigger) and adjust the compressor threshold accordingly. Furthermore, various specific implementations can determine the compressor threshold using information about the power supply (e.g., battery manufacturer or model).

[0072] Furthermore, various implementations of the headset 10 may be configured to assign separate compressor thresholds to separate ANR profiles. For example, as described in U.S. Patent Application No. 16 / 953,272 (incorporated by prior reference), the headset may be configured to apply separate ANR profiles based on one or more inputs or triggers. The ANR profiles may differ from one another based on several acoustic characteristics, including but not limited to the maximum level of noise cancellation, filter coefficients, equalization, spectrum, etc. The headset 10 may enable switching of ANR profiles using, for example, an interface 550. For example, the interface 550 may include a touch interface, button, switch, or other physical interface for selecting or switching between ANR configurations. In some implementations, the interface 550 may include a mechanical switch, such as a two-position or three-position switch, which allows the user to instruct the controller 560 to switch between profiles, ANR configurations, and / or other settings. In some examples, the interface 550 includes a mechanical switch that allows the user to switch between at least two ANR configurations. For example, a mechanical switch allows switching between one use-specific ANR configuration (e.g., an aviation-specific ANR configuration) and another use-specific ANR configuration (e.g., a broadcast-specific ANR configuration or a music playback-specific ANR configuration).

[0073] Furthermore, various implementations of the headset 10 may be configured to sample the voltage drop of the power supply 540 in response to the connection of an accessory in the headset 10 and / or the disconnection of an accessory 420 (Figure 4) in the headset 10. In some cases, the ANR circuit 570 is further configured to adjust the compressor threshold based on the type of accessory 420 connected to the headset 10, for example, the controller 560 may assign a battery usage profile to the accessory 420. In such cases, the controller 560 may be configured to adjust the compressor threshold 660 based on both the sampled voltage drop of the power supply 540 and the type of accessory 420 connected to the headset 10. Non-limiting examples of accessories include a cable (e.g., a connector cable) configured to attach the headset 10 to at least one other device (e.g., an electronic flight bag, an external sensor module, etc.), a microphone or array of microphones, one or more image capture devices such as a camera, one or more photodetectors, a LiDAR sensor, or one or more optical capture devices such as an optoelectronic device (e.g., for scanning or transmitting / receiving), a positioning system such as a global positioning system (GPS), a local positioning system, or an indoor positioning system. An additional trigger that may be used, for example, to adjust the compressor threshold 660 to initiate sampling of the voltage drop of the power supply 540 is described in U.S. Patent Application No. 16 / 953,272 (incorporated by reference previously).

[0074] Various implementations include headsets configured to perform active noise reduction (ANR) according to the methods described herein. Further embodiments of ANR that may be compatible with the implementations herein are described in U.S. Patent Application No. 16 / 788,365, filed February 12, 2020, “Computational Architecture for Active Noise Reduction,” which is incorporated in its entirety by reference.

[0075] As described herein, in contrast to conventional audio devices, the headset 10 in various implementation forms offers several advantages. For example, the headset 10 in various implementation forms is configured to extend battery life and / or improve performance compared to conventional headsets by enabling performance and power management functions that are tuned and matched based on power supply characteristics. Furthermore, in some cases, the headset 10 is configured for use in multiple scenarios and / or industries, ranging from casual use by consumers to professional use by pilots, military personnel, sports coaches, or entertainment professionals. The headset 10 is configured to apply separate ANR compression thresholds based on power supply characteristics. The headset 10, as shown and described according to various implementation forms, can improve the user experience and performance compared to conventional audio devices.

[0076] Some elements of the drawings in this specification are illustrated and described as individual elements in block diagrams and may be referred to as “circuits,” but unless otherwise specified, these elements can be implemented as analog circuits, digital circuits, or one or more microprocessors that execute software instructions, or a combination thereof. Software instructions may include digital signal processing (DSP) instructions. Operations can be performed by analog circuits or by microprocessors performing software that performs operations equivalent to analog operations. Unless otherwise specified, signal lines can be implemented as individual analog signal lines or digital signal lines, as a single individual digital signal line with appropriate signal processing capabilities for processing individual acoustic signal streams, or as elements of a wireless communication system. Some processes may be described in block diagrams. Activities performed in each block may be performed by one or more elements and may be temporally separated. Elements performing block activities may be physically separated. Unless otherwise specified, acoustic signals may be encoded and transmitted in either digital or analog format. Conventional digital-to-analog converters and analog-to-digital converters may be excluded from these diagrams. Some of the diagrams may include logic elements such as decision blocks, comparators, or logic gates. The output of a logic element is designated as "0" (corresponding to "NO", "Low", or "Open Circuit") or "1" (corresponding to "YES", "High", or "Closed Circuit").

[0077] In various implementations, components described as "joined" to one another can be joined along one or more interfaces. In some implementations, these interfaces may include joints between separate components, while in others, they may include interconnections that are rigidly and / or integrally formed. That is, in some cases, "joined" components can be formed simultaneously to define a single continuous member. However, in other implementations, these joined components may be formed as separate members and then joined by known processes (e.g., soldering, fastening, ultrasonic welding, joining). In various implementations, accessories described as "linked" (e.g., electronic components) can be linked via conventional wired and / or wireless means so that these accessories can communicate data with each other. Furthermore, subcomponents within a given component can be considered linked via conventional paths, although these are not necessarily illustrated.

[0078] Other embodiments not specifically described herein are also within the scope of the following claims. Elements of different implementations described herein may be combined to form other embodiments not specifically described above. Elements may be removed from the structures described herein without adversely affecting the operation of the structures described herein. Furthermore, various distinct elements may be combined into one or more individual elements to perform the functions described herein. [Explanation of symbols]

[0079] 10 headsets 70 Electronic equipment 100 Aviation Headsets 105 Eartips (e.g., ear cups) 110 Headband (e.g., over the head bridge) 115 Electronic components (e.g., microphones such as boom microphones) 120 connection cables 125 Control Module 130 Arcuate part 132 Housing 132A Right Housing 132B Left Housing 134 Spring band 136 pads 136A Right Pad 136B Left Pad 138 Contour Surface 140 Boom 142 Rotatable base 144 Microphone 146 connectors 148 Earpiece (e.g., earphone) connector cable 150 ear tips 310 Around-Ear Headphones 320 ear tips 330 Headband 340 Head Cushion 400 eartips 420 Accessories 500 transducers 510 Sensor 520 Communication Devices 530 Accessory Port Connector 540 Power supply 550 Interface 560 Control Circuit 570 ANR circuit 580 ANR engine 590 Amplifier 600 Feedback Microphone 610 Feedback Loop 624 Feedback Filter 630 Feedforward Loop 640 Compressor Threshold Loop 650 ANR Compressor 660 Compressor Threshold 670 Voltage detector 672 Sampling Circuit 674 Fixed resistor 676 Control Switch 680 Voltage drop amplifier (or power supply sensing amplifier) 690 LPF 690 Low-pass filter 692 Amplifier 694 Voltage Regulator 696 Low-pass filter 700 Envelope Detector 710 Power Monitoring System

Claims

1. It is a headset, At least one electroacoustic transducer configured to provide an audio output, A power supply for supplying power to at least one electroacoustic transducer, A control circuit, Applying active noise reduction (ANR) to ambient noise using at least one of the aforementioned electroacoustic transducers, Sampling the voltage drop of the aforementioned power supply, Adjusting the compressor threshold for the ANR based on the sampled voltage drop of the power supply, A control circuit is configured to perform the following: A headset equipped with [features / equipment].

2. The headset according to claim 1, wherein the power supply includes one or more batteries.

3. The headset according to claim 2, wherein the one or more batteries are selected from a group of different batteries having different chemical properties.

4. The headset according to claim 3, wherein the voltage drop of the first battery among the batteries is different from the voltage drop of the second battery among the batteries.

5. The headset according to claim 1, wherein the power supply includes an external power supply.

6. The headset according to claim 5, wherein the external power supply includes a wired connection to an aircraft power supply.

7. The headset according to claim 1, wherein adjusting the compressor threshold improves the ANR performance of the headset.

8. The headset according to claim 7, wherein the improved ANR performance is characterized by at least one of greater noise reduction in the audio output or an increase in gain in the audio output.

9. The headset according to claim 1, wherein adjusting the compressor threshold increases the battery life for the headset.

10. The headset according to claim 1, wherein the adjustment of the compressor threshold is performed automatically in response to the sampled voltage drop deviating from the voltage drop threshold.

11. The headset according to claim 10, wherein the compressor threshold is adjusted without user input commands.

12. The headset according to claim 10, wherein the control circuit is configured to repeatedly sample the voltage drop and to dynamically adjust the compressor threshold in response to the sampled voltage drop deviating from the voltage drop threshold.

13. The headset according to claim 12, wherein the repeating method includes at least one of continuous sampling or periodic sampling.

14. The headset according to claim 1, wherein adjusting the compressor threshold includes reducing the compressor threshold in order to reduce power consumption by the headset.

15. Sampling the voltage drop is necessary because of the following characteristics of the power supply: The headset according to claim 1, comprising determining at least one of the following: power impedance, charging or discharging state, battery quality, battery chemical properties, connection quality, or voltage level over time.

16. The headset according to claim 1, further comprising an interface that allows a user to input at least one characteristic of the power supply, wherein the control circuit is configured to adjust the compressor threshold based on the at least one characteristic of the power supply.

17. Further including feedforward microphone input and feedback microphone input, The control circuit includes an ANR engine and a compressor. The headset according to claim 1, wherein the compressor is configured to compress the feedback loop gain from the feedback microphone input according to the compressor threshold before it enters the ANR engine.

18. The headset according to claim 17, wherein the compressor threshold is determined using a compressor threshold control loop having the voltage drop of the power supply as an input and compressor threshold adjustment as an output.

19. The headset according to claim 1, wherein the control circuit is further configured to adjust the power monitoring system based on the sampled voltage drop.

20. The headset according to claim 1, wherein sampling the voltage drop of the power supply comprises transmitting a set of test signals to the power supply and measuring the voltage response for each of the set of test signals.

21. A method for controlling an active noise reduction (ANR) headset, wherein the method is: Applying ANR to ambient sound using the aforementioned headset, Sampling the voltage drop of the power supply for the headset, Adjusting the compressor threshold for the ANR based on the sampled voltage drop of the power supply, Methods that include...

22. The power supply according to claim 21, wherein the power supply includes one or more batteries.

23. The method according to claim 22, wherein the one or more batteries are selected from a group of different batteries having different chemical properties, and the voltage drop of the first battery among the batteries is different from the voltage drop of the second battery among the batteries.

24. The method according to claim 21, wherein the power supply includes an external power supply, and the external power supply includes a wired connection to an aircraft power supply.

25. The method according to claim 21, wherein adjusting the compressor threshold improves the ANR performance of the headset when providing audio output, the improved ANR performance being characterized by at least one of greater noise reduction in the audio output or an increase in gain in the audio output.

Images