Methods, microphones, computer-readable media, and systems

Abstract

This disclosure describes a wireless microphone system that allows one or more microphones to wirelessly communicate with a receiver. Additionally, the wireless microphone system allows multiple microphones to be used interchangeably with the receiver. To ensure communication between the receiver and the one or more microphones, the receiver may occasionally send a synchronization signal to the one or more microphones. In response to receiving the synchronization signal, at least one of the one or more microphones may determine that the clock of the at least one microphone has drifted from a master audio clock of the receiver. The at least one microphone may then adjust its audio clock to resynchronize the audio clock of the microphone with the master audio clock of the receiver.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims priority to U.S. Provisional Application No. 63 / 310,996, titled "Wireless Microphone System," filed on February 16, 2022, and U.S. Provisional Application No. 63 / 353,962, titled "Synchronization of Transmitter and Receiver in a Wireless Microphone System," filed on June 21, 2022, the entire disclosures of which are incorporated herein by reference.

Background Art

[0002] Although various microphones are available in the consumer market, it is desirable to provide a wireless microphone system that has additional flexibility to adapt to various configurations.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

[0004] The following summary presents a simplified overview of certain features. This summary is not an extensive overview and is not intended to identify key or critically important elements.

[0005] Examples of a wireless microphone system, its elements, and methods of operating a wireless microphone system are described herein.

[0006] In some respects, a modular wireless microphone system is described in which multiple microphones can be used interchangeably to communicate wirelessly with the same wireless receiver. The number and type of wireless microphones communicating with the wireless receiver may be changed based on the desired use case. Various microphones in the wireless microphone system are configured to communicate wirelessly with the wireless receiver using the same one or more data protocols, and as a result these microphones are interchangeable within the wireless microphone system.

[0007] In a further aspect, a specific wireless receiver can be used as an intermediary to wirelessly receive audio from one or more of these wireless microphones as audio data and transmit the digital or analog signals representing the audio to other devices connected to the wireless receiver. In a further example, other user devices such as smartphones, tablets, and laptop computers can be configured (e.g., programmed) to communicate wirelessly directly with one, two, or more wireless microphones.

[0008] The additional aspects described herein disclose a technique for synchronizing data between a radio receiver and one or more radio microphones. The radio receiver may transmit a synchronization signal to one or more radio microphones. In response to receiving the synchronization signal, at least one of the one or more radio microphones may determine that the clock of at least one microphone has drifted from the receiver's master audio clock. At least one microphone may adjust its audio clock to resynchronize its audio clock with the receiver's master audio clock.

[0009] These and other features and potential benefits are detailed below. [Brief explanation of the drawing]

[0010] Several features are shown in the attached drawings as examples, not as an exhaustive list. In the drawings, the same number refers to the same element.

[0011] [Figure 1] An example of a modular wireless microphone system is shown. [Figure 2] Here is another example of a modular wireless microphone system. [Figure 3] This shows an example of how data can be transmitted wirelessly as downstream and / or upstream data. [Figure 4A] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 4B] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 5A] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 5B] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 6A] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 6B] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 7A] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 7B] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 8A] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 8B] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 9A] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 9B] Various exemplary configurations of the modular wireless microphone system 100 are shown. [Figure 10A] Shows various exemplary configurations of the modular wireless microphone system 100. [Figure 10B] Shows various exemplary configurations of the modular wireless microphone system 100. [Figure 10C] Shows various exemplary configurations of the modular wireless microphone system 100. [Figure 11A] Shows various exemplary configurations of the modular wireless microphone system 100. [Figure 11B] Shows various exemplary configurations of the modular wireless microphone system 100. [Figure 12] Shows an exemplary block diagram of various elements of the modular wireless microphone system. [Figure 13A] Shows an exemplary charging case that can be part of the modular wireless microphone system. [Figure 13B] Shows an exemplary charging case that can be part of the modular wireless microphone system. [Figure 13C] Shows an exemplary charging case that can be part of the modular wireless microphone system. [Figure 14] Is a flowchart showing an exemplary process for synchronizing audio data transmitted by a wireless microphone to a wireless receiver. [Figure 15A] Is a flowchart showing an exemplary process for synchronizing audio data between a wireless microphone and a wireless receiver. [Figure 15B] Is a flowchart showing an exemplary process for synchronizing audio data between a wireless microphone and a wireless receiver. [Figure 16A] Is a flowchart showing an exemplary process for synchronizing audio data between a wireless microphone and a wireless receiver. [Figure 16B] Is a flowchart showing an exemplary process for synchronizing audio data between a wireless microphone and a wireless receiver. [Figure 17]This flowchart illustrates an exemplary process for synchronizing multiple transmitters. [Figure 18] An example of a modular wireless microphone system is shown, configured to synchronize at least one wireless transmitter with at least one receiver by adjusting the audio clock of the at least one transmitter. [Modes for carrying out the invention]

[0012] The accompanying drawings form part of this disclosure and illustrate several examples of this disclosure. It should be understood that the examples shown in the drawings and / or described herein are non-exclusive and other examples of how this disclosure may be carried out exist.

[0013] Figure 1 shows an example of a modular wireless microphone system 100. In the illustrated example, the system 100 may include one or more wireless microphones 101, a wireless receiver 103, and / or a charging case 104. The one or more wireless microphones may be any one or more types, such as, but not limited to, one or more wireless lavalier microphones such as microphones 101b and 101c, one or more wireless handheld microphones, one or more wireless shotgun microphones, and / or any other type of wireless microphone. In Figure 1, microphone 101a represents any type of wireless microphone, and microphone 101d represents any type of wired microphone. If the wired microphone 101d is modified by a wireless transceiver 102 (e.g., connected to the wireless transceiver 102 by a wire), as will be further described below, the modified microphone (combination of elements 101d and 102) can be transformed into a wireless microphone. In other words, when referring to wireless microphone 101 here, this is intended to include wireless microphones 101a, 101b, and 101c (for this example), as well as wired microphone 101d when modified by wireless transceiver 102.

[0014] Each wireless microphone 101 may be configured to communicate wirelessly with a wireless receiver 103. Wireless communication with each wireless microphone 103 may include transmitting audio data representing the sound detected by each microphone 101 wirelessly to one or more wireless receivers 103. For example, wireless microphone 101a may detect a sound, generate audio data representing the detected sound, and transmit it wirelessly to the wireless receiver 103. Similarly, wireless microphones 101b and / or 101c may each detect a sound, generate audio data representing the respective detected sound, and transmit it wirelessly to the wireless receiver 103. More than one of the microphones 101 may simultaneously transmit audio data to the wireless receiver 103. For example, wireless microphone 101a may transmit its audio data to the wireless receiver 103, and wireless microphone 101b may also transmit its audio data to the wireless receiver 103. When multiple microphones 101 are simultaneously transmitting audio data to the same radio receiver 103, the audio data from each microphone 101 may be treated by the radio receiver 103 as separate channels or tracks. For example, audio data received from microphone 101a may be treated by the radio receiver 103 as the left audio channel, and audio data received from microphone 101b may be treated by the radio receiver 103 as the right audio channel. In another example, a single microphone (such as microphone 101a) may acquire sound through two separate audio channels (e.g., left and right stereo audio channels) and transmit audio data that separately represents these two audio channels. Any data transmitted by a microphone to the receiver is referred to here as downstream data.

[0015] Each wireless microphone 101 may include one or more types of microphone elements that implement one or more polar patterns. For example, each wireless microphone 101 may include a bidirectional microphone element and / or a cardioid microphone element, and / or implement a single polar pattern or a plurality of selectable polar patterns.

[0016] Downstream data may also include, for example, data indicating the configuration (e.g., state) of the microphone 101 transmitting the downstream data. For example, downstream data may include data identifying the microphone, data indicating the microphone's mode, data indicating one or more of the microphone's capabilities, data indicating the microphone's battery status, data indicating the measured radio signal strength, data indicating the microphone's gain, data indicating the data protocol used to transmit and / or receive data, data indicating the audio data rate, data indicating the audio codec used, data protocol handshake information, etc.

[0017] Wireless communication may further include upstream data transmitted wirelessly by the wireless receiver 103 to one or more of the microphones 101. Upstream data may include, for example, data identifying the wireless receiver, data indicating the mode of the wireless receiver, data indicating one or more capabilities of the wireless receiver (e.g., supported wireless channels, supported codecs, supported data rates, number of supported simultaneous audio channels, etc.), data indicating the battery status of the wireless receiver, data indicating the measured wireless signal strength, data indicating the gain of the wireless receiver, data indicating the data protocol used, data protocol handshake information, back-channel (upstream) audio data, etc.

[0018] One or more of the microphones 101 may already be wireless, and / or one or more of the microphones 101 may be wired microphones that have been reconfigured to operate as wireless microphones. For example, if microphone 101d itself is not wireless, a wireless transceiver 102 may be electrically connected to microphone 101d (for example, via the XLR connector of microphone 101d) to make it a wireless microphone. The wireless transceiver 102 may be electrically connected to one or more digital and / or analog signal connectors of microphone 101d, for example.

[0019] The wireless receiver 103 may include a display screen 110 and a user interface such as one or more buttons, switches, etc. (e.g., button 111). The display screen 110 may show the user information such as the current status of the wireless receiver 103, the current status of one or more of the wireless microphones 101 (e.g., transmission status, connection status, on / off status, battery status), the current status of the wireless link with one or more of the wireless microphones (e.g., signal strength or quality), the applied gain (GAIN), volume level, applied equalization, the codec used for decoding, audio data rate or quality, and / or any other information as desired. The user interface may allow the user to turn the wireless receiver 103 on and off, connect and disconnect one or more of the wireless microphones 101, and / or control any other functions of the wireless receiver 103 as desired.

[0020] The charging case 104 may be configured to hold (e.g., seal) one or more of the other elements of the modular system 100 and charge their batteries. For example, the charging case 104 may be configured to electrically connect to any one or more of the wireless microphones 101 simultaneously or one at a time and charge the rechargeable batteries of the wireless microphones 101. The charging case 103 may further be configured to electrically connect to the wireless receiver 103 simultaneously or at different times with one or more microphones 101 that are being charged and charge the batteries of the wireless receiver 103. Each of the wireless microphones 101 and wireless receivers 103 may include one or more electrical contacts, charging ports, and / or other types of electrical connectors configured to be electrically connectable to the charging case 104. The charging case 104 may have a power cord for connecting to an external power source, for example by plugging it into a standard wall outlet, and the external power may be converted and used by the charging case 104 to charge the rechargeable batteries of the wireless microphones 101 and / or wireless receivers 103. The charging case 104 may also have its own rechargeable battery, which can be charged via a power cord. Once charged, the rechargeable battery of the charging case 104 can be used to charge the wireless microphone 101 and / or wireless receiver 103 even when the charging case 104 is not connected to an external power source via its power cord.

[0021] Each wireless microphone 101 may include a user interface such as one or more buttons, switches, or touch-sensitive surfaces for accepting user input. User input may be used to turn the wireless microphone on or off, adjust the gain of the wireless microphone, adjust the polarity pattern of the microphone, connect to a specific wireless receiver, and / or adjust the operating configuration of each wireless microphone 101 for similar purposes.

[0022] Figure 2 shows another configuration of the modular wireless microphone system 100. This is identical to the configuration of the modular wireless microphone system 100 shown in Figure 1, but differs in that a user device such as a smartphone is used as the wireless receiver 203 instead of the wireless receiver 103. That is, in the example shown in Figure 2, one or more of the wireless microphones 101 can directly communicate wirelessly with a user device (e.g., a smartphone) that functions as a wireless receiver 203, without requiring a wireless communication intermediary device such as a dedicated wireless receiver (e.g., wireless receiver 103). The modularity of the modular wireless microphone system 100 allows the wireless receiver (implemented using a smartphone or other user device) 203, wireless receiver 103, and other compatible wireless receivers to be used interchangeably with the same microphone 100. Not only can specific wireless receivers be made interchangeable in the modular wireless microphone system 100, but any element of the modular wireless microphone system 100 can be made interchangeable, added, and removed. This provides the user with a flexible modular system experience. For example, at one given time, the modular wireless microphone system 100 may use one active subset of microphones 100 (e.g., microphones 101b and 101c) (e.g., to receive audio data from that set), at another given time, the modular wireless microphone system 100 may be reconfigured to use a different active subset of microphones 100 (e.g., microphone 101a), and at yet another given time, the modular wireless microphone system 100 may be reconfigured again to use yet another active subset of microphones 100 (e.g., microphones 101a and microphone 101b). In yet another exemplary configuration, the modular wireless microphone system 100 may use any or all of microphones 101a, 101b, and 101c, and / or further wireless microphones 101 (and / or types of microphones) not explicitly shown in Figures 1 and 2, to transmit audio data to a wireless receiver 103 or 203.Furthermore, for any of these various configurations of the modular wireless microphone system 100, any selected type of wireless receiver may be used in combination with a selected microphone 101, such as wireless receiver 103 or wireless receiver 203.

[0023] User devices that may implement the wireless receiver 203 may be, for example, smartphones, table computers, laptop computers, and / or any other user devices capable of wirelessly communicating with one or more microphones 101. The user device may be configured, by executable software or the like, to directly communicate with one or more microphones 101 using an appropriate wireless communication protocol and present an interactive user interface. This interactive user interface may allow the user to view similar information displayed by the wireless receiver 103 and / or control the functions of the user device in a manner similar to that described herein for the wireless receiver 103.

[0024] In any of the various configurations of the modular wireless microphone system 100, the wireless microphone 101 and either the wireless receiver 103 or 203 may each be configured to wirelessly transmit upstream and / or downstream data using the same one or more data protocols. The data protocols for upstream and downstream data may each include, for example, Classic Bluetooth®, Bluetooth Low Energy (BLE), BLE Audio, proprietary data protocols, any other standard or non-standard data protocols, and / or any combination of any of the above. A potential advantage of using the BLE data protocol is that it can take advantage of relatively low power consumption for wirelessly monitoring, transmitting, and / or receiving data compared to other wireless data protocols. The same data protocol may always be used for all types of wireless data communication between the wireless microphone 101 and the wireless receiver 103 / 203, or the data protocol may be switched between two or more different data protocols depending on the operating mode of any of the elements of the modular system 100. To transmit audio data via a data protocol, the wireless microphone 101 and / or wireless receivers 103 / 203 may embed (e.g., encapsulate) the audio data within a PDU of a second data protocol as a data packet, frame, and / or other type of protocol data unit (PDU) of a first data protocol. For example, if the second data protocol is BLE, the wireless microphone 101 and wireless receivers 103 / 203 may each be configured to transmit data (e.g., audio data and / or control data) by encapsulating the PDU of the first data protocol within a BLE link layer packet, and / or to receive data (e.g., voice data) by extracting and reading such encapsulated PDUs. The encapsulated audio data packet may be any standard or non-standard data protocol.As used herein, the term data “packet” is understood to also include data “frames,” as well as any other logical groups of data that may be used by the relevant data protocol used to represent audio data.

[0025] Figure 3 shows an example of how data may be transmitted wirelessly as downstream and / or upstream data. The transmitted data may include, for example, audio data and / or any other type of data described herein. In the illustrated example, the data stream (downstream or upstream) may include multiple PDUs 301 (e.g., 301a, 301b, etc.). Each PDU 301 may be a PDU of the second data protocol described above. For example, a PDU 301 may be a BLE link layer packet. Each PDU 301 may include a header 302 (e.g., headers 302a and 302b) and a payload 303 (e.g., payloads 303a and 303b). The header 302 may include, for example, identification information such as the source device for each PDU 301 (e.g., the source address or other identifier of the wireless microphone 101 that wirelessly transmits the audio data embedded in the associated PDU 301) and the destination device (e.g., the destination address), timing information such as a timestamp, information related to the payload 303 such as the payload length and / or type and / or the length and / or type of the PDU 301, a CRC (Cyclic Redundancy Check), a header, and / or any other information specific to a particular second data protocol. The payload 303 may include, for example, any other data that is desirable to be transferred between devices. For example, each payload 303 may include audio data, commands, timestamps, and / or other data that is desirable to be transferred between devices. At least a portion of the data in the payload 303 may be contained in one or more PDU 310s of the first data protocol (e.g., PDU 310a, 310b, 310c, and 310d). For example, one of the wireless microphones may generate one or more PDU 310 containing audio data (and / or other data) as downstream data, encapsulate or arrange one or more of these PDU 310 into a PDU 301 (for example, encapsulate PDU 310a and 310b into PDU 301a), and transmit one or more PDU 301 to a wireless receiver 203 or 303.Next, the wireless receiver 103 or 203 may decapsulate or extract PDU 310 from the received PDU 301, extract audio data from the received PDU 301, and interpret the audio data (or other data) therein. The same process may be used for upstream data. Depending on which wireless receiver (and / or what type of wireless receiver) the wireless microphone 101 is sending audio data to, the audio data may be formatted in PDU 301 and / or a different type of PDU 301 may be used. For example, if the wireless microphone 101 is connected via BLE to a wireless receiver 103 which may be a first type of wireless receiver such as a dedicated wireless audio receiver, the wireless microphone 101 may transmit audio data encapsulated in a first type of PDU using a first format to the wireless receiver 103. Alternatively, if the same wireless microphone 101 is connected via BLE to a wireless receiver 203 which may be a second type of wireless receiver such as a smartphone, the wireless microphone 101 may transmit audio data to the wireless receiver 303 using a second format (different from the first format) and / or encapsulated in a second type of PDU (different from the first type of PDU).

[0026] The PDUs of the first data protocol and / or the second data protocol (e.g., PDU301 and / or 310) may have any length, data rate, PDU rate, and format as needed. The length and rate of a set of PDUs may be predetermined static lengths or rates, and may vary from PDU to PDU.

[0027] In addition to transmitting audio data, wireless microphones may wirelessly transmit other types of data. For example, each wireless microphone 101 may transmit indications of its configuration, such as microphone mode, microphone identification, desired audio data rate or quality, codec used for encoding and / or decoding audio data, and data protocol used for transmitting audio data.

[0028] Each wireless microphone 101 may have a wireless connection channel (such as a BLE connection) with a wireless receiver 103 or 203. If the connection channel is a BLE connection, the BLE connection may have a specific BLE Generic Attribute Profile (GATT) service having one or more data characteristics for its transmitted channel audio. This may encapsulate encoded audio frames. Furthermore, the wireless connection may transmit one or more audio streams from the wireless microphone 101 to the wireless receiver 103 or 203. Here, each audio stream may have one or more audio channels, such as a mono audio stream or a stereo audio stream. The wireless microphone 101 and / or the wireless receiver 103 / 203 may configure the streams as desired. For example, the streams may be configured as a left audio channel, a right audio channel, other types of mono audio channels, or stereo audio.

[0029] As an example of the flow of audio data from a wireless microphone 101 to a wireless receiver 103 or 203, a wireless microphone 101, such as a wireless microphone 101a, may receive sound through its microphone element and convert the analog signal from the microphone element into a digital audio signal using an analog-to-digital (A / D) converter. Alternatively, if the wireless microphone 101a is, for example, a pulse density modulation (PDM) microphone, the wireless microphone 101a may generate a digital audio signal without requiring analog-to-digital conversion. The wireless microphone 101 may transmit the digital audio signal to a digital signal processing unit, for example, via an I2S bus. This digital signal processing unit may apply one or more desired digital signal processing functions (such as equalization, gain adjustment, etc.). Additionally or alternatively, the wireless microphone 101 may transmit the digital audio signal to the digital signal processing unit, for example, via a TDM bus. The resulting processed digital audio signal may be encoded using a CODEC, such as an OPUS CODEC. Next, the encoded audio signal is packaged into one or more PDUs (such as BLE link layer packets), timestamped, modulated to a radio frequency, and transmitted via the antenna of the radio microphone 101a. At the receiving end, the PDU is radio received by the antenna of the radio receiver 103 or 203, demodulated from the radio frequency, decoded (e.g., using an OPUS CODEC), depacked, and processed. The decoding results in, for example, pulse code-modulated (PCM) audio data, which may be added to an accumulation buffer based on the timestamp of each received PDU. An asynchronous process in the radio receiver 103 or 203 may extract PCM audio data from this buffer in response to the buffer containing a sufficient amount (e.g., at least a threshold amount) of PCM audio data.If the wireless receiver 203 is a user device such as a smartphone having an existing operating system or other platform, and the process is implemented via software instructions executed on the operating system or other platform, the software instructions may package the PCM audio data into a format suitable for the operating system or other platform and, if desired, pass it to the operating system or other platform for further processing.

[0030] Figures 4 to 11 show various exemplary configurations of the modular wireless microphone system 100. One aspect of the present disclosure assumed herein is that the modular wireless microphone system 100 may be reconfigurable to connect one or more of the microphones 101 to one or more other devices of one or more types, such as wireless receivers 103 or 203, computers, mixers, cameras, and / or audio headsets, in countless ways. Thus, the illustrated configurations are merely examples, and many other possible configurations (e.g., interconnections) of the various elements of the modular wireless microphone system 100 exist.

[0031] For example, the various elements of the modular wireless microphone system 100 are compatible to communicate with each other in various combinations, allowing the modular wireless microphone system 100 to flexibly respond to the specific needs of a user in a particular situation. Furthermore, the modular wireless microphone system 100 can be scaled as needed, from a single wireless microphone to the required number of simultaneous / parallel wireless microphones to provide the required number of audio channels. For example, if a user requests two or more audio channels, the user may connect two or more of the wireless microphones 101 wirelessly (or via wire) to other devices capable of receiving audio channels from those wireless microphones 101. If a user requests only a single audio channel, the user may use only a single wireless microphone 101. If other devices are directly compatible with the wireless microphone 101, the user may connect the wireless microphone 101 directly to the other devices (wirelessly or via wire). If other devices are not directly compatible with the wireless microphone 101 (for example, if other devices are not compatible with the wireless audio protocol transmitted by the wireless microphone 101), the user may connect a wireless receiver 103 (or 203) between the wireless microphone 101 and the other device, and the wireless receiver 103 (or 203) may perform the necessary signal and format conversions to receive audio from the wireless microphone 101 and transmit that audio to the other device.

[0032] Figures 4A and 4B show two exemplary configurations of the modular wireless microphone system 100. In the configuration of Figure 4A, one of the wireless microphones (e.g., wireless microphone 101a) transmits audio to the wireless receiver 203 via a wireless connection such as BLE, which encapsulates other data protocols. In the configuration of Figure 4B, one of the wireless microphones (e.g., wireless microphone 101a) transmits audio to the wireless receiver 203 via a wired connection such as USB (Universal Serial Bus) (e.g., USB-C). Alternatively, wireless receiver 103 may be replaced by wireless receiver 203. Wireless receiver 203 (or 103) may transmit upstream data to wireless microphone 101a via a wireless connection (e.g., BLE data connection) or a wired connection (e.g., USB-C connection). The configurations of Figures 4A and 4B may be useful, for example, to transmit only a single audio channel from a single microphone.

[0033] Figures 5A and 5B show two other exemplary configurations of the modular wireless microphone system 100. In the configuration of Figure 5A, one of the wireless microphones (e.g., wireless microphone 101b) is wirelessly communicating with the wireless receiver 203. In the configuration of Figure 5B, multiple wireless microphones (e.g., two wireless microphones 101b and 101c) are wirelessly communicating with the wireless receiver 203 simultaneously. In both configurations, the wireless connections may each be BLE, for example, encapsulating other data protocols. In both configurations of Figures 5A and 5B, the wireless receiver 203 may be replaced with the wireless receiver 103 instead. In a configuration having two wireless microphones, one of the wireless microphones (e.g., wireless microphone 101b) may transmit audio data that is interpreted and treated as a first (e.g., left) audio channel by the wireless receiver 203, and the other wireless microphone (e.g., wireless microphone 101c) may transmit audio data that is interpreted and treated as a second (e.g., right) audio channel by the wireless receiver 203. These exemplary configurations may be useful, for example, for transmitting one channel of audio (Figure 5A) or multiple simultaneous (parallel) channels of audio (Figure 5B). In the configuration of Figure 5B, the wireless receiver 203 (or 103) may have a single set of wireless receiver circuits configured to demultiplex audio data received wirelessly from multiple microphones (e.g., audio data received wirelessly simultaneously from microphones 101b and 101c). The wireless receiver 203 (or 103) may further be configured to mix the two audio channels in a desired manner and generate a digital or analog signal representing the mixed audio channel.

[0034] Figures 6A and 6B show two further exemplary configurations of the modular wireless microphone system 100. In the configuration of Figure 6A, several different wireless microphones (e.g., two wireless microphones 101a and 101b) are simultaneously communicating wirelessly with the wireless receiver 203. In the configuration of Figure 6B, one of the wireless microphones (e.g., wireless microphone 101a) communicates wirelessly with the wireless receiver 103. In both configurations of Figures 6A and 6B, the wireless connections may each be BLE, for example, encapsulating other data protocols. In both configurations, the wireless receiver 203 can be replaced with the wireless receiver 103 instead. In a configuration having two wireless microphones, one of the wireless microphones (e.g., wireless microphone 101a) may transmit audio data that is interpreted and treated as a first (e.g., left) audio channel by the wireless receiver 203, and the other wireless microphone (e.g., wireless microphone 101b) may transmit audio data that is interpreted and treated as a second (e.g., right) audio channel by the wireless receiver 203. The exemplary configuration in Figure 6 may be useful, for example, for transmitting audio on one channel (Figure 6B) or audio on multiple simultaneous (parallel) channels (Figure 6A).

[0035] Figures 7A and 7B show two further exemplary configurations of the modular wireless microphone system 100. In the configuration of Figure 7A, several different wireless microphones (e.g., two wireless microphones 101b and 101c) are simultaneously communicating wirelessly with the wireless receiver 103. In the configuration of Figure 7B, one of the wireless microphones (e.g., wireless microphone 101b) communicates wirelessly with the wireless receiver 103. In both configurations of Figures 7A and 7B, the wireless connections may each be BLE, for example, encapsulating other data protocols. In both configurations, the wireless receiver 103 may be replaced by a wireless receiver 203 instead. In a configuration having two wireless microphones, one of the wireless microphones (e.g., wireless microphone 101b) may transmit audio data that is interpreted and treated by the wireless receiver 103 as a first (e.g., left) audio channel, and the other wireless microphone (e.g., wireless microphone 101c) may transmit audio data that is interpreted and treated by the wireless receiver 103 as a second (e.g., right) audio channel. These exemplary configurations may be useful, for example, for transmitting audio on one channel (Figure 7B) or audio on multiple simultaneous (parallel) channels (Figure 7A).

[0036] Figures 8A and 8B show two further exemplary configurations of the modular wireless microphone system 100. In Figure 8A, several different wireless microphones (e.g., two wireless microphones 101a and 101c) are simultaneously communicating wirelessly with a wireless receiver 103. Each wireless connection may be, for example, BLE encapsulating other data protocols. Alternatively, the wireless receiver 103 may be replaced with a wireless receiver 203. One of these wireless microphones (e.g., wireless microphone 101a) may transmit audio data that is interpreted and treated by the wireless receiver 103 as a first (e.g., left) audio channel, and the other wireless microphone (e.g., wireless microphone 101c) may transmit audio data that is interpreted and treated by the wireless receiver 103 as a second (e.g., right) audio channel. The configuration in Figure 8A may be useful, for example, for transmitting multiple simultaneous (parallel) channels of audio.

[0037] The configuration in Figure 8B shows a wireless microphone (e.g., wireless microphone 101a) connected to another device 801 via a wired connection. The wired connection may be, for example, a 3.5mm TRRS connection, or any other type of connection for transmitting analog and / or digital signals. The other device 801 may be any type of device capable of receiving audio from the wireless microphone, and is shown as, for example, a camera. However, device 801 may be any other type of audio device or audio / visual device, such as a mixer, wired receiver, or laptop computer. Figure 8B may be useful, for example, for transmitting single-channel audio or multi-channel audio (such as left / right stereo audio) to device 801. For example, device 801 may be a video camera that records or acquires video while audio associated with the video is received via microphone 101. Device 801 may synchronize the audio with the video in any desired manner.

[0038] Figures 9A and 9B show two further exemplary configurations of the modular wireless microphone system 100. In both exemplary configurations of Figures 9A and 9B, the wireless receiver 103 may be connected to another device, such as device 801, via a wired connection. The wired connection may be, for example, a 3.5mm TRRS connection, or any other type of connection for transferring analog and / or digital signals. While the wireless receiver 103 is connected to device 801, the wireless receiver 103 may simultaneously wirelessly receive audio data from one or more of the microphones 101, such as microphone 101a. The wireless connection between the wireless receiver 103 and the wireless microphones may be, for example, BLE encapsulating other data protocols. The wireless receiver 103 may extract the audio data received via the wireless connection and transfer a signal based on the audio data to device 801. For example, the wireless receiver 103 may convert the audio data into an analog audio signal, which may be transmitted to device 801 via the wired connection. As another example, the wireless receiver 103 may transmit audio data, or other data derived from audio data, to device 801 via a wired connection. This configuration may be useful when device 801 is not necessarily compatible with wireless connection data protocols, or when device 801 does not have wireless communication capabilities at all.

[0039] The configuration in Figure 9B is similar to that in Figure 9A, except that, in addition to the wired connection, the wireless receiver 103 is physically connected to the device 801 via a mounting device (e.g., physically mounted). The wireless receiver 103 may be mounted on a shoe-type mounting device, for example, on which digital cameras are typically mounted. The mounting device may be a "cold" mount (e.g., a cold shoe mount) where no data and / or power is transferred between the wireless receiver 103 and the device 801 via the mounting device. However, the mounting device may alternatively be a "hot" mount (e.g., a hot shoe mount) where power and / or data is transferred between the wireless receiver 103 and the device 801. In the "hot" mount scenario, since audio data is transferred via the mounting device, a separate wired connection (e.g., a 35mm TRRS connection) is redundant and unnecessary. When mounted on device 801, the wireless receiver 103 may be configured to mount on device 801 in a low-profile or low-profile manner, for example, by having its own mounting device connection on the back of the wireless receiver 103 and / or by being foldable relative to that mounting connection.

[0040] Figures 10A, 10B, and 10C show further exemplary configurations of the modular wireless microphone system 100. In the configurations of Figures 10A and 10C, the wireless receiver 103 or wireless receiver 203 may be connected via a wired connection to other devices such as an audio headset 1001, earphones, or other types of audio-compatible user listening devices. The wired connection may be, for example, a 3.5mm TRRS connection (or other headphone jack type), a Lightning® connection (which may include an adapter for connecting to headphones, such as a Lightning / 3.5m adapter), or any other type of connection for transferring analog and / or digital signals. Instead of a wired connection between the wireless receiver 103 / 203 and the audio headset 1001, a wireless connection such as via Bluetooth or BLE may be used. While the wireless receiver 103 is connected to the audio headset 1001 (wired or wirelessly), the wireless receiver 103 may also simultaneously wirelessly receive audio data from one or more microphones 101, such as microphone 101a. The wireless connection between the wireless receiver 103 and the wireless microphone may be, for example, BLE, which encapsulates other data protocols. The wired receiver 103 may extract audio data received via the wireless connection and transfer signals based on the audio data to the audio headset 1001. For example, the wireless receiver 103 may convert the audio data into an analog audio signal, which can then be transmitted to the audio headset 1001 via the wired connection. Alternatively, the wireless receiver 103 may transmit audio data, or other data derived from audio data, to the audio headset 1001 via the wired connection. This configuration may be useful if the audio headset 1001 is not necessarily compatible with wireless connection data protocols, or if the audio headset 1001 does not have wireless communication capabilities at all.As another example, the audio headset 1001 may be connected to a wireless receiver 103 via (for example) a 3.5mm TRRS connection, and a first person wearing the audio headset 1001 can speak into the microphone of the audio headset 1001 at the wireless receiver 103. The first person's voice may be transmitted to a hardware receiver 103, which may then wirelessly transmit it back to the microphone 101a via a reverse link (for example, a back channel). A second person at the microphone 101a may have audio headphones plugged into or communicating with the microphone 101a, and the microphone 101a may transmit the transmitted voice from the first person to the second person's audio headphones. In this way, the second person can hear the transmitted voice coming back from the first person at the wireless receiver 103.

[0041] In the configuration shown in Figure 10B, the wireless microphone 101 (e.g., wireless microphone 101a) may be directly connected to the audio headset 1001 via a wired connection. The wired connection may be, for example, a 3.5mm TRRS connection, or any other type of connection for transmitting analog and / or digital signals. In this exemplary configuration, the wireless microphone 101 may temporarily function as a wired microphone.

[0042] Figures 11A and 11B show two further exemplary configurations of the modular wireless microphone system 100. In the configuration of Figure 11A, the wireless receiver 103 may be connected via a wired connection to another device 1101, such as a laptop computer, desktop computer, mixer, or other type of device capable of receiving and / or processing audio signals. For non-limiting explanatory purposes only, the following description assumes that device 1101 is a laptop computer. The wired connection may be, for example, a USB connection such as a USB-C connection, or any other type of connection for transferring analog and / or digital signals. While the wireless receiver 103 is connected to the laptop computer 1101, the wireless receiver 103 may simultaneously wirelessly receive audio data from one or more of the microphones 101, such as microphone 101a. The wireless connection between the wireless receiver 103 and the wireless microphones may be, for example, BLE encapsulating other data protocols. The wireless receiver 103 may extract audio data received via the wireless connection and transfer a signal based on the audio data to the laptop computer 1101. For example, the wireless receiver 103 may transmit audio data, or other data derived from audio data, to the laptop computer 1101 via a USB-C wired connection. Alternatively, the wireless receiver 103 may convert the audio data into an analog audio signal, which may be transmitted to the laptop computer 1101 via another type of wired connection. This configuration may be useful if the laptop computer 1101 is not necessarily compatible with the Wireless Connection Data Protocol (e.g., does not have a BLE communication card) or if the laptop computer 1101 does not have wireless communication capabilities at all.

[0043] In the configuration shown in Figure 11B, the wireless microphone 101 (e.g., wireless microphone 101a) may be directly connected to the laptop computer 1101 via a wired connection. The wired connection may be, for example, a USB connection such as a USB-C connection, or any other type of connection for transferring analog and / or digital signals. In this exemplary configuration, the wireless microphone 101 may temporarily function as a wired microphone.

[0044] Figure 12 shows an exemplary block diagram of any of the elements of the modular wireless microphone system 100. Elements 101, 102, 103, 104 and / or 203 may or may not be partially or fully implemented as a device as shown in Figure 12. Device 1200 may be implemented, for example, as a computing device that executes stored instructions and / or as a hardwired circuit that may or may not execute stored instructions. In the illustrated example, device 1200 may include, or be connected to, any of, one or more processors 1201, storage 1202 (which may include one or more computer-readable media such as memory), wireless interface 1203, wired interface 1207, input device 1205, output device 1206, and / or one or more microphone elements (each having a microphone driver circuit) 1208.

[0045] One or more processors 1201 may be configured to execute instructions stored in storage 1202. When executed by one or more processors 1201, the instructions may cause device 1200 to perform any of the functions described herein that are performed by any of the elements 101, 102, 103, 104 and / or 203 of the modular wireless microphone system 100. For example, the instructions may cause one or more processors 1201 to configure device 1200 to implement, enable, disable and / or modify device settings such as data transmission settings, microphone polarity pattern settings, digital signal processing settings, and user interfaces.

[0046] The wireless interface 1203 may include or be coupled to one or more antennas and may transmit and / or receive upstream data and / or downstream data, such as data wirelessly transmitted between one of the wireless microphones 101 and the wireless receiver 103 or 203. The wired interface 1207 may include one or more physical connections for receiving and / or transmitting digital and / or analog signals, such as the USB (e.g., USB-C) connection described above or other types of connections (e.g., Apple's Lightning) and / or the TRRS connection described above. If the wireless interface is part of the wireless receiver 103 or 203, the wireless interface 1203 may include circuitry configured to receive, extract and demultiplex audio data received from multiple wireless microphones 101. For example, if a wireless receiver 103 or 203 is receiving simultaneously from two wireless microphones 101 (as in the configuration of Figure 5B), the wireless interface 1203 of the wireless receiver 103 or 203 may be configured to demultiplex the audio data received wirelessly via a common transmission medium (e.g., air) shared by the transmissions of both wireless microphones 101. Depending on the data protocol used by the wireless microphones 101 to transmit the audio data, the audio data received and extracted by the wireless receiver 103 or 203 may be attributed to the wireless microphone source 101 via received data related to the source wireless microphone that transmitted the audio data (e.g., identifying the source wireless microphone).

[0047] The input device 1205 and / or output device 1206 may implement any user interface for specific elements of the modular wireless microphone system 100. For example, the buttons on the microphone 101a may correspond to the input device 1205, and the display screen of the wireless receiver 103 or 203 may correspond to the output device 1206.

[0048] Power may be supplied to any element of device 1200 as needed. Although not explicitly shown, device 1200 may include power connections for receiving internal and / or external power sources (such as a battery).

[0049] Figures 13A to 13C show detailed examples of the charging case 104. Figures 13A and 13B are top views of the charging case 104 with the lid 1301 removed. Figure 13C is a side view of the charging case 104 with the lid 1301 placed in its designated position and closed.

[0050] Referring to Figure 13A, the charging case 104 may include a main body (e.g., a housing) 1302 (which may be made of plastic, for example). The main body 1302 may include an internal portion containing one, two, or more recesses 1303 (e.g., 1303a and 1303b). One, two, or more microphones 101 are fitted into, or at least partially positioned within, these one, two, or more recesses 1303. The recesses 1303 may have a shape related to the wireless microphone 101 placed therein. For example, each recess 1303 may have a shape that matches the external shape of at least a portion of the wireless microphone 101 placed therein. Each recess 1303 may further include one, two, or more electrical contacts 1304 (e.g., contact pair 1304a and contact pair 1304b) configured to electrically contact one, two, or more corresponding electrical contacts of the wireless microphone 101 placed within the recess 1303. The charging case 104 may also include one or more magnets that are positioned, molded, and / or otherwise configured to hold the wireless microphone 101 in place while it is being charged. The magnets may be optionally positioned in recesses 1303, integrated into electrical contacts 1304, and / or otherwise arranged to interface with one or more magnets or magnetic materials of the wireless microphone 101 when it is being charged in the charging case 1404.

[0051] Figure 13B is similar to Figure 13A, except that two of the wireless microphones 101 (in this example, wireless microphones 101b and 101c) are positioned in their respective recesses 1303a and 1303b so that their electrical contacts are electrically connected to the electrical contact 1304. In this configuration, wireless microphones 101b and 101c may be charged simultaneously by the charging case 104.

[0052] Figure 13C is a side view of the charging case 104 with the lid 1301 closed to the body 1302 so that the interior is sealed by the body 1302 and the lid 1301. The lid 1301 may also be considered part of the body 1302. The lid 1301 may have a hinge on one side that allows it to pivot between an open position and a closed position (for inserting or removing the wireless microphone 101). Alternatively, the lid may be set in place by friction fitting onto the body 1302 and may be completely removed as needed without a hinge. In addition, Figure 13C shows that the wireless receiver 103 may also be electrically connected to the charging case 104 so that it is charged simultaneously with the wireless microphones 101b and 101c as needed. In this example, the wireless receiver 103 may have one, two, or more electrical contacts that can be electrically connected to one, two, or more electrical contacts on the outer (e.g., bottom) surface of the charging case 104, and may be charged simultaneously with the charging of one or more microphones by the charging case 104. The wireless receiver 103 and / or the charging case 104 may have one or more physical connectors (which may be part of an electrical connector) that physically hold (e.g. mount) the wireless receiver 103 to the charging case 104 during charging.

[0053] Figure 14 is a flowchart illustrating an exemplary process aimed at synchronizing audio data transmitted by one of the wireless microphones 101 with a wireless receiver 103 or 203, and establishing a connection between the wireless microphone 101 and the wireless receiver 103 or 203. Each of the wireless microphones 101 and the wireless receiver 103 or 203 may operate its own local clock. Each wireless microphone 101 may include a timestamp in one or more of the PDUs 301 (e.g., header 302) or 310 based on its local clock. However, the various local clocks of different devices may not necessarily be synchronized with each other. In fact, they are likely not synchronized unless intentionally synchronized. That is, if an audio data packet transmitted by a wireless microphone 101 (e.g., a BLE link layer packet) is associated with a specific timestamp based on the local clock of that wireless microphone 101 (e.g., that timestamp is stamped), that timestamp may be meaningless to a wireless receiver (which has its own independent local clock). One way to overcome this is to determine information related to the offset between the local clock of the wireless microphone 101 and the local clock of the wireless receiver 103 or 203 and provide it to the wireless microphone 101 and / or the wireless receiver 103 or 203. For example, it may be desirable to determine a common "presentation time" (PT) for each audio data packet (which may be the time the audio contained in the data packet was physically present in the microphone). By determining an accurate estimate of the PT for an audio data packet, a receiving device (e.g., camera 801) can know the exact timing at which each received audio packet was generated, and use this information to synchronize the received audio data from a given microphone with other sets of audio data (e.g., from other microphones transmitting their own audio data at the same time) or with video that may be recorded and / or received while the microphone is transmitting audio data.

[0054] Referring to the illustrative flowchart in Figure 14, in step 1401, the wireless receiver 103 or 203 can write a clock characteristic to a data packet and wirelessly transmit the data packet to one of the given wireless microphones 101. The clock characteristic may be, for example, the value of any clock available to the wireless receiver 103 or 203 (e.g., a high-resolution and / or high-precision timer). For example, if the wireless receiver 203 uses Apple's iOS operating system, the clock may be the main iOS audio / video clock, a system clock with nanosecond resolution, which is a "media timer". Google's Android operating system (which may be used instead by the wireless receiver 203) may use a similar system clock that can be used as the clock used to generate the clock characteristic. As another example, the wireless receiver 103 or 203 may have an internal hardware-based clock or have access to an external clock source as a timer. Regardless of the type of clock used by the radio receiver 103 or 203, the radio receiver 103 or 203 may generate clock characteristics based on the clock value (for example, so as to be equal to the clock value). Step 1401 may be performed after a radio connection with the radio microphone 101 has been established and before audio subscription to the radio microphone 101. The radio microphone 101 may generate an acknowledgment packet (or other type of packet) in response to a data packet and radio transmit it to the radio receiver 103 or 203. The radio receiver 103 or 203 may measure the round-trip time (using its local clock) from sending the message in step 1401 to receiving the acknowledgment packet in step 1402.

[0055] The radio receiver 103 or 203 may repeat this process of steps 1401 and 1402 multiple times, as shown by steps 1403, 1404 and 1405. For example, the radio receiver 103 or 203 may transmit a clock characteristic, receive a corresponding acknowledgment, and measure the round-trip time, the sum of three, four, five, or any other sum.

[0056] The wireless receiver 103 or 203 may determine the transmission delay (the time required for a one-way transmission from the wireless microphone 101 to the wireless receiver 103 or 203) based on multiple measured round-trip times. For example, the wireless receiver 103 or 203 may estimate the transmission delay by taking the average or median of the round-trip times and dividing that average or median by 2. For example, if the measured round-trip times are A milliseconds, B milliseconds, and C milliseconds, the transmission delay may be determined as the median (A, B, C) / 2. Once the wireless receiver 103 or 203 has determined the transmission delay, it may take the transmission delay into account by adding it to the timestamp value of the clock characteristic and write the clock characteristic one last time. For example, if the time of the wireless receiver's local clock is X and the transmission delay is Y, the wireless receiver 103 or 203 may transmit a data packet with a timestamp of X+Y.

[0057] Subsequently, in step 1406, the wireless receiver 103 or 203 may subscribe to the audio data of the wireless microphone 101, and in steps 1407 and 1408 (and for each subsequent audio data packet), the wireless microphone 101 may transmit multiple audio data packets, for example, by embedding the audio data into one or more BLE data packets to form audio data packets. Each audio data packet transmitted by the wireless microphone 101 contains, or is otherwise associated with, a timestamp value representing the packet's PT on a local clock time basis of the wireless receiver. PT may represent a transmission delay offset. The wireless microphone 101 may use this value to adjust the timestamp included in the transmitted audio data packet. BLE is used as a first protocol for establishing a connection between the wireless microphone 101 and the wireless receiver 103 or 203 (for example, when performing any of steps 1401 to 1406), and once the connection is established, the wireless microphone 101 may then shift to a second transmission protocol for transmitting audio data packets (for example, by embedding audio in BLE data packets as shown here with respect to Figure 3).

[0058] As described above, the wireless receiver 103 or 203 may synchronize its clock with the wireless microphone 101 before subscribing to the audio data of the wireless microphone 101. After subscribing to the audio data of the wireless microphone 101, the wireless receiver 103 or 203 and one or more wireless microphones 101 may need to synchronize their clocks to ensure that the data received by the wireless receiver 103 or 203 is accurate. Figures 15A and 15B show flowcharts illustrating, for example, an exemplary process for synchronizing the audio data transmitted by the wireless microphone to the wireless receiver after the wireless receiver has subscribed to the audio data of the wireless microphone.

[0059] In step 1505, the transmitter (e.g., wireless microphone 101) may receive a first synchronization signal from the receiver (e.g., wireless receiver 103). In step 1510, the transmitter (e.g., wireless microphone 101) may store a predetermined number of audio samples, for example, in response to the reception of the first synchronization signal. The predetermined number of audio samples may be a nominal number of audio samples stored in an audio sampling queue. The nominal number of audio samples may be defined by the receiver (e.g., wireless receiver 103) before the receiver subscribes to the transmitter's audio data. The transmitter may discard all audio samples except the nominal number of audio samples stored in the audio sampling queue. That is, the transmitter may delete or erase audio samples exceeding the nominal number of audio samples, for example, based on or in response to the reception of the first synchronization signal. Additionally, in step 1515, the transmitter may set the elapsed synchronization signal count to zero. The elapsed synchronization signal count may be set to zero, for example, based on or in response to the reception of a first synchronization signal. Setting the elapsed synchronization signal count to zero may include resetting the counter. Additionally or alternatively, setting the elapsed synchronization signal count to zero may include resetting the increment register to zero.

[0060] In step 1520, the transmitter may receive a second synchronization signal from the receiver. The second synchronization signal may be received at a predetermined interval (e.g., 10 to 20 milliseconds) after the first synchronization signal. Each subsequent synchronization signal may be received at a predetermined interval. In step 1525, the transmitter may store the address of the synchronization signal. The address of the synchronization signal may be stored in the transmitter's hardware register. In step 1530, the transmitter (e.g., the transmitter's processor) may, for example, detect the address of the synchronization signal in the hardware register. In response to the detection of the address of the synchronization signal, the transmitter may generate an interrupt in step 1535. Additionally or alternatively, the transmitter may increment an elapsed synchronization signal counter in step 1540.

[0061] In step 1545, the transmitter may determine the current number of audio samples in the audio sampling queue. The determination of the current number of audio samples may be, for example, based on or in response to an interrupt. Additionally, the determination of the current number of audio samples may be made by querying or otherwise monitoring the audio sampling queue and determining the number of audio samples contained therein. In step 1550, the transmitter may determine whether the current number of audio samples is equal to the previous number of audio samples. If they are equal, the transmitter may transmit the audio samples to the receiver in step 1552. Preferably, the audio samples are transmitted to the receiver via a wireless connection, as described above. The step of transmitting audio samples to the receiver may include transferring a certain number of audio samples from the audio sampling queue to a transmit queue. Additionally or alternatively, the transmitter may convert the digital audio samples to analog audio samples before transmitting the audio samples to the receiver. The transmitter may use a digital-to-analog converter (DAC) to convert the digital audio samples to analog audio samples. In some embodiments, the number of audio samples transmitted to the receiver in step 1552 may occur at predetermined intervals or in a fixed regularity. For example, the number of audio samples may be transmitted using the technique described above in Figure 3. That is, the number of audio samples may be transmitted as blocks or chunks of data. Alternatively, the number of audio samples may be transmitted continuously from the transmitter to the receiver (e.g., streamed).

[0062] If the current number of audio samples is not equal to the previous number of audio samples, the transmitter may determine in step 1555 whether the current number of audio samples is equal to a predetermined number of audio samples. If the current number of audio samples is equal to a predetermined number of audio samples, the transmitter may transmit audio samples to the receiver in step 1557. Audio samples may be transmitted using the techniques described above in step 1552. In step 1559, the transmitter may set the elapsed synchronization signal count to zero and return to step 1520 to monitor for the next synchronization signal.

[0063] If the current number of audio samples is not equal to a predetermined number of audio samples, the transmitter may recognize that the transmitter's audio clock is drifting. That is, the transmitter may determine that its audio clock is drifting. In order to determine the direction of the drift and / or to adjust the transmitter's audio clock, the transmitter may determine in step 1560 the difference between the current number of audio samples and the previous number of audio samples. In this regard, if the current number of audio samples is greater than the previous number of audio samples, a positive integer may indicate that the transmitter's audio clock is drifting in a direction that is faster than the receiver's master audio clock. On the other hand, if the result is a negative integer, the transmitter may determine that the audio clock is drifting in a direction that is slower than the receiver's master audio clock. In step 1565, the transmitter may determine, for example, the time difference between the transmitter's audio clock and the receiver's master audio clock. The time difference may be determined by multiplying the elapsed synchronization signal count by the synchronization signal interval.

[0064] In step 1570, the transmitter may determine (e.g., calculate) the audio clock error. The audio clock error may be determined using the difference between the current number of audio samples and the previous number of audio samples determined in step 1560, and / or the time difference determined in step 1565. The audio clock error may be the difference in Hertz (Hz) between the transmitter's audio clock and the receiver's master audio clock. In step 1575, the transmitter may adjust the audio clock frequency of its audio clock. That is, the transmitter may adjust the audio clock frequency of its audio clock in the opposite direction to the determined (e.g., detected) error and / or drift. For example, if the transmitter determines that the audio clock is drifting in the direction of being slower than the master audio clock, the transmitter may adjust its audio clock to increase the frequency of the audio clock. By increasing the audio clock, the transmitter may increase the rate at which the microphone acquires audio samples. Alternatively, if the transmitter determines that the audio clock is drifting faster than the master audio clock, the transmitter may adjust its audio clock to reduce its frequency. By reducing the audio clock, the transmitter may acquire audio samples at a lower (less frequent) rate. Additionally or alternatively, adjusting the audio clock may include adjusting the frame boundaries. As will be described in detail later with respect to Figure 18, the audio clock frequency may be adjusted by writing a value to a register.

[0065] Once the audio clock has been adjusted, the transmitter may, in step 1580, set the elapsed synchronization signal count to zero. Additionally or alternatively, the transmitter may, in step 1580, set the previous number of audio samples to the current number of audio samples. These steps, individually or in combination, allow the transmitter to detect drift in near real-time, thereby ensuring that multiple transmitters remain synchronized with the receiver's master clock.

[0066] In step 1585, the transmitter may transmit an audio sample to the receiver. The audio sample may be transmitted using the techniques described above in step 1552. The receiver may combine the audio sample with audio samples received from one or more second transmitters. Additionally or alternatively, the audio sample may be used to generate an audio file. The audio file may be played back immediately. Alternatively, the audio file may be stored for later editing, playback, and / or replay. After transmitting the audio sample to the receiver, the transmitter may return to step 1520 and monitor for further synchronization signals.

[0067] Figures 16A and 16B show flowcharts illustrating other exemplary processes for synchronizing audio data transmitted by the wireless microphone to the wireless receiver after the wireless receiver has subscribed to the audio data from the wireless microphone.

[0068] In step 1605, the audio interface of the transmitter (e.g., wireless microphone 101) may be configured to generate an audio sample event for each audio sample received by the transmitter. As will be described in detail with respect to Figure 18, the audio interface may be configured as an electrical serial bus interface (e.g., inter-IC sound (I)) to connect multiple digital audio devices together and / or to communicate audio data between integrated circuits in an electronic device. 2The interface may be an S) interface. An audio sample event may include, for example, receiving a data block via the transmitter's input (e.g., a microphone). The data block may be a datagram or any other suitable data chunk received via the input. Preferably, the data chunk is a 24-bit PCM sample.

[0069] After the audio interface is configured to generate audio sample events, in step 1610, a transmitter counter may be configured. Preferably, the counter may be configured to increment, for example, based on or in response to the reception of an audio sample event. In step 1615, the counter may further be configured to store and reset the count upon reception of a synchronization signal. The count may be a predetermined audio sample event that the transmitter expects to receive between synchronization signals. Additionally or alternatively, storing the count may include setting the counter to an initial count of zero. The counter may also be configured to reset upon reception of a synchronization signal. In this regard, the counter may be configured to reset immediately after reception of a synchronization signal. Additionally or alternatively, the counter may be configured to output the count to a register or any other suitable memory and then reset the counter. As will be described in detail below with respect to step 1665, the counter may be used to determine whether the transmitter clock is drifting from a master clock that can be maintained by the receiver (e.g., receiver 103). The configuration of the audio interface and the counter may be done as part of the initial setup between the transmitter and / or receiver. Additionally or alternatively, the audio interface and counter may be configured before the transmitter is purchased and / or sold. That is, the audio interface and counter may be configured according to the factory settings.

[0070] After the audio interface and counter are configured, and after the receiver (e.g., receiver 103) subscribes to the audio data of the transmitter (e.g., microphone 101), the transmitter may receive a first synchronization signal from the receiver in step 1620. The first synchronization signal may be transmitted over a wireless communication link between the transmitter and the receiver. Alternatively, the first synchronization signal may be transmitted over a wired connection between the transmitter and the receiver.

[0071] In step 1625, the transmitter may store a predetermined number of audio samples, for example, based on the reception of a first synchronization signal. Additionally, the transmitter may record the number of received audio samples, for example, using the counter described above. The predetermined number of audio samples may be the nominal number of audio samples received by the transmitter. As described above, the nominal number of audio samples may be pre-configured. Additionally or alternatively, the nominal number of audio samples may be determined by a counter. That is, the nominal number of audio samples may be indicated by the number of audio sample events recorded by the counter. In this regard, the nominal number of audio samples may be indicated by the number of audio sample events recorded by the counter between the first synchronization signal (i.e., sync0) and the second synchronization signal (i.e., sync1). In some cases, a receiver (e.g., radio receiver 103) may configure the transmitter by the nominal number of audio samples. In step 1630, the transmitter may set the elapsed synchronization signal count to zero. Setting the elapsed synchronization signal count to zero may include resetting the counter and / or increment register to zero.

[0072] In step 1635, the transmitter may receive a second synchronization signal (i.e., syncn, n≧2) from the receiver. The second synchronization signal may be received at a predetermined interval (e.g., 10 to 20 milliseconds) after the first synchronization signal. Each subsequent synchronization signal may be received at a predetermined interval. In step 1640, the transmitter may store the address of the synchronization signal, for example, in the transmitter's hardware registers. More specifically, the address of the synchronization signal may be stored in the hardware registers of the transmitter's processor. In step 1645, the transmitter (e.g., the transmitter's processor) may detect the address of the synchronization signal in the hardware registers. In step 1650, the transmitter may generate an interrupt, for example, based on or in response to the detection of the address of the synchronization signal in the hardware registers. In step 1655, the transmitter may increment an elapsed synchronization signal counter, for example, based on or in response to the detection of the address of the synchronization signal in the hardware registers.

[0073] In step 1660, the transmitter may retrieve the last stored counter value, for example, based on or in response to the reception of a second synchronization signal. As described above, the counter value may be stored in a register or other suitable memory location in response to the reception of a synchronization signal. In step 1660, the counter value may be retrieved from a register or other suitable memory location. In step 1665, the transmitter may determine, for example, whether the transmitter's clock has drifted from the receiver's master clock by comparing the current counter value with a previous / expected counter value. In some examples, the transmitter may compare the current counter value with a preceding counter value (i.e., a second amount of audio samples received between syncn-2 and syncn-1) based on a first amount of audio samples received since the previous synchronization signal (i.e., when syncn was received). Additionally or alternatively, the transmitter may compare the current counter value with an expected counter value based on, for example, the number of audio samples the transmitter is expected to receive between synchronization signals. As described above, the number of audio samples that the transmitter is expected to receive between synchronization signals may be pre-configured and / or configured during the initial setup / synchronization between the transmitter and receiver. If the counter value is equal to the previous / predicted counter value, the transmitter may determine in step 1699 that its audio clock has not drifted and may send multiple audio samples to the receiver. The process may then be repeated by returning to step 1635.

[0074] If the counter value is not equal to the previous / predicted counter value, the transmitter may recognize that the transmitter's audio clock is drifting. That is, the transmitter may determine that its audio clock is drifting. In step 1670, the transmitter may determine, for example, the difference between the current counter value and the preceding counter value to determine the degree and / or direction of the drift. Additionally or alternatively, in step 1670, the transmitter may determine the difference between the current counter value and the predicted (e.g., configured) counter value (e.g., the amount of audio samples received between synchronization signals). If the current counter value is greater than the preceding counter value and / or the predicted counter value (e.g., a positive integer), the transmitter may determine that its audio clock is drifting faster than the receiver's master audio clock. On the other hand, if the result is a negative integer, the transmitter may determine that the audio clock is drifting slower than the receiver's master audio clock.

[0075] In step 1675, the transmitter may determine, for example, the time difference between the transmitter's audio clock and the receiver's master audio clock. The time difference may be determined by multiplying the elapsed synchronization signal count by the synchronization signal interval.

[0076] In step 1680, the transmitter may determine (e.g., calculate) the audio clock error. The audio clock error may be determined using the difference between the current count value and the leading / predicted counter value determined in step 1670, and / or the time difference determined in step 1675. The audio clock error may be the difference in Hertz (Hz) between the transmitter's audio clock and the receiver's master audio clock.

[0077] In step 1685, the transmitter may adjust the audio clock frequency of the transmitter's audio clock. That is, the transmitter may adjust the audio clock frequency in the opposite direction to the determined (e.g., detected) error and / or drift. For example, if the transmitter determines that the audio clock is drifting slower than the master audio clock, the transmitter may adjust the audio clock to increase its frequency. By increasing the audio clock, the transmitter may increase the rate at which the microphone acquires audio samples. Alternatively, if the transmitter determines that the audio clock is drifting faster than the master audio clock, the transmitter may adjust the audio clock to decrease its frequency. By decreasing the audio clock, the transmitter may acquire audio samples at a lower (less frequent) rate. Additionally or alternatively, adjusting an audio block may include adjusting frame boundaries. In step 1690, the transmitter may, for example, set the elapsed synchronization signal count to zero after the audio clock has been adjusted. As described above, the steps shown in Figures 16A and 16B allow the transmitters to detect drift in near real-time, thereby ensuring that the multiple transmitters remain synchronized with the receiver's master clock.

[0078] In step 1695, the transmitter may determine whether the audio sample queue is within an acceptable range. That is, the transmitter may determine whether the audio sample queue is too large. Allowing the audio sample queue to be too large may increase the end-to-end latency of the audio samples being played out at the receiver relative to the capture time of those samples at the microphone element. Alternatively, the transmitter may determine whether the audio sample queue is too small, and therefore whether audio samples will be missed. The acceptable range may be the predicted number of audio samples + / - n. If the audio sample queue is within an acceptable range, the transmitter may transmit the audio samples to the receiver in step 1699. As described above, the audio samples may be transmitted to the receiver via the wireless connection. Additionally or alternatively, the transmitter may convert the digital audio samples (e.g., digital PCM samples) to a compressed format before transmitting them to the receiver. The compressed format may reduce the data rate required on the wireless interface. The transmitter may generate digital audio samples in a compressed format using a transcoder function (e.g., a codec) or encoder to generate a compressed format. In some embodiments, the audio samples may be sent to the receiver at predetermined intervals or in a fixed regularity. Alternatively, the audio samples may be streamed from the transmitter to the receiver. The receiver may receive the digital audio samples in the compressed format and generate audio samples by performing a reverse transcoding function (e.g., a codec) or decoder. The receiver may then combine these audio samples with audio samples received from one or more second transmitters. Additionally or alternatively, the audio samples may be used to generate an audio file. The audio file may be played back immediately. Alternatively, the audio file may be stored for later editing, playback, and / or replay. After sending the audio samples to the receiver, the transmitter may return to step 1635 and monitor for further synchronization signals.

[0079] If the audio sample queue is not within an acceptable range, the transmitter may adjust the number (e.g., quantity) of audio samples that the audio sample queue can process in step 1697. If the number of audio samples in the audio sampling queue becomes too large, audio samples may be discarded. Conversely, if the number of audio samples in the audio sampling queue becomes too small, dummy (e.g., mute) codewords may be inserted into the audio sampling queue. After adjusting the size of the audio sample queue, the transmitter may send the audio samples to the receiver in step 1699.

[0080] The process described above and shown in Figures 15A, 15B, and / or Figures 16A and 16B may be performed at regular intervals when the receiver subscribes to the transmitter's data. As described above, the process ensures that the transmitter and receiver remain synchronized and provides a way for the transmitter to adjust its audio clock to ensure that the devices remain synchronized.

[0081] As described above, a receiver can subscribe to data from multiple transmitters. Figure 17 shows an example of the process of synchronizing multiple transmitters. In particular, Figure 17 shows receiver 103, a first transmitter 101a, and a second transmitter 101b. Receiver 103, the first transmitter 101a, and the second transmitter 101b may be any of the receivers or transmitters described herein. Although Figure 17 shows two transmitters, it is understood that many more transmitters may be included in the system shown in Figure 17 without deviating from the description herein.

[0082] In step 1705, receiver 103 may transmit a synchronization signal to the first transmitter 101a and / or the second transmitter 101b. The synchronization signal may be wirelessly broadcast by receiver 103 to the first transmitter 101a and / or the second transmitter 101b. Additionally or alternatively, receiver 103 may transmit (e.g., send) the first synchronization signal to the first transmitter 101a and the second synchronization signal to the second transmitter 101b. In some embodiments, the first and second synchronization signals may be separate transmissions. In step 1710, the first transmitter 101a may adjust the first audio clock using, for example, the steps described above. Similarly, in step 1715, the second transmitter 101b may adjust the second audio clock using the process described above. It should be understood that steps 1710 and / or 1715 may be skipped if, for example, it is determined that either the first transmitter 101a and / or the second transmitter 101b does not need to adjust and / or correct its audio clock. In step 1720, the first transmitter 101a may transmit (send) first audio data to the receiver 103. The first audio data may be sent to the receiver 103 via a first wireless connection between the first transmitter 101a and the receiver 103. Similarly, in step 1725, the second transmitter 101b may transmit (send) second audio data to the receiver 103. The second audio data may be sent to the receiver 103 via a second wireless connection between the second transmitter 101b and the receiver 103. The receiver 103 may combine the first audio data and the second audio data to generate an audio file. Audio files may be immediately played back and / or stored for editing and / or playback.

[0083] In step 1730, receiver 103 may send other synchronization signals to the first transmitter 101a and / or the second transmitter 101b. The synchronization signals may be sent using any of the techniques described above with respect to step 1705. Furthermore, receiver 103 may transmit synchronization signals to the first transmitter 101a and / or the second transmitter 101b at predetermined intervals (e.g., 10 to 20 milliseconds). In step 1735, the first transmitter 101a may adjust the first audio clock. In step 1740, the second transmitter 101b may adjust the second audio clock. In step 1745, the first transmitter 101a may transmit (send) third audio data to receiver 103. The third audio data may be a continuation of the first audio data transmitted to receiver 103 in step 1720. In step 1750, the second transmitter 101b may transmit (send) the fourth audio data to the receiver 103. The fourth audio data may be, for example, the next part of the second audio data transmitted in step 1725. As described above, the receiver 103 may combine the third audio data and the fourth audio data to generate an audio file. In some examples, the third audio data and the fourth audio data may be added to the audio file generated from the first audio data and the second audio data.

[0084] Although only two cycles are shown in Figure 17, it is understood that the cycles shown in Figure 17 may continue as long as receiver 103 is subscribed to the first transmitter 101a and / or the second transmitter 101b. As described above, the process shown in Figure 17 provides a technique that allows the transmitter and receiver to maintain synchronization without receiving a transmitter timestamp synchronization signal from the receiver. Furthermore, the transmitter that adjusts its audio clock ensures that these devices maintain synchronization even if the transmitter's audio clock drifts in different directions.

[0085] Figure 18 shows an example of a modular wireless microphone system configured to synchronize at least one wireless transmitter with at least one receiver by adjusting the audio clock of the at least one transmitter. The modular wireless microphone system shown in Figure 18 includes a transmitter 101, a receiver 103 and / or a computing device 1870.

[0086] The transmitter 101 may be a microphone configured to acquire one or more audio samples via an input device. Preferably, the transmitter 101 is a wireless microphone. The transmitter 101 may include an input device 1805, an analog-to-digital converter (ADC) 1807, a clock 1815, and / or a processor 1820. The input device 1805 may be any suitable microphone configured to acquire audio samples (e.g., singing, instrumental music, etc.). The ADC 1807 may be configured to convert the analog audio acquired via the input device 1805 into digital samples to be stored in an audio sampling queue (e.g., an audio sampling queue 1827, described in more detail below).

[0087] Clock 1815 may be an oscillator configured to generate a clock frequency for audio applications. Clock 1815 may be suitable for use as a source clock for audio peripherals. Preferably, clock 1815 is a 32 MHz crystal oscillator. Clock 1815 may have a frequency adjustable in two frequency bands between 11.176 MHz and 11.402 MHz and between 12.165 MHz and 12.411 MHz. Clock 1815 may have low jitter suitable for audio applications. In audio applications where audio data arrives asynchronously to the on-chip clock, the frequency of clock 1815 may be adjusted to maintain synchronization with receiver 103. In this regard, the frequency may be configured via a value written to a register (not shown). For the frequency range from 11.176 MHz to 11.402 MHz, three values ​​may be written to the register. For example, the minimum value (e.g., 12519) may cause the clock 1815 to oscillate at 11.176 MHz, the median value (e.g., 15298) may cause the clock 1815 to oscillate at 11.28 MHz, and the maximum value (e.g., 16068) may cause the clock 1815 to oscillate at 11.402 MHz. Three values ​​may also be written to the register for the frequency range from 12.165 MHz to 12.411 MHz. For example, the minimum value (e.g., 36834) may cause the clock 1815 to oscillate at 12.165 MHz, the median value (e.g., 39854) may cause the clock 1815 to oscillate at 12.288 MHz, and the maximum value (e.g., 42874) may cause the clock 1815 to oscillate at 12.411 MHz. By updating the values ​​stored in the registers, the audio clock of transmitter 101 (e.g., clock 1815) is adjusted, and any drift determined by transmitter 101 is corrected so that transmitter 101 and receiver 103 maintain synchronization by adjusting a certain number of audio samples acquired by input device 1805.

[0088] The processor 1820 may be configured to perform one or more audio applications. The processor 1820 may be a system-on-a-chip (SOC) or an application-specific integrated circuit (ASIC) such as a Nordic® nRF5340 semiconductor. As shown in Figure 18, the processor 1820 may include hardware registers 1822, timers 1824, audio interface 1826, counters 1828, DAC 1830, and / or I / O unit 1832, but it is understood that the processor 1820 may include additional or fewer components beyond the scope of this disclosure. For example, the processor 1820 may include an audio encoder (not shown). The audio encoder may reduce the data rate required to send packets wirelessly to the receiver 103.

[0089] Hardware register 1822 may be configured to store the address of the synchronization signal received from receiver 103. For example, hardware register 1822 may be any suitable register associated with processor 1820 configured to store the address of the synchronization signal received from receiver 103. Hardware register 1822 may be configured to generate an interrupt in response to having stored the address of the synchronization signal. Additionally or alternatively, hardware register 1822 may generate an interrupt based on the address of the synchronization signal written therein.

[0090] Timer 1824 may be configured to perform time intervals. In some examples, the time interval may be defined via user input. Timer 1824 may be driven by a high-frequency clock source such as clock 1815. Timer 1824 may include a 4-bit prescaler (not shown) that can divide the timer input clock. Timer events may trigger tasks on other system peripherals. For example, a timer event may cause transmitter 101 to send audio data to receiver 103. Timer 1824 may be configured to operate in either timer mode or counter mode. In timer mode, the internal counter register of Timer 1824 may be incremented by one each time a counting task is triggered. This means that the timer frequency and prescaler are not available in counter mode.

[0091] The audio interface 1826 may be configured to receive one or more audio samples. The audio interface 1826 can receive inter-IC sound (I 2 S) Interface may be included. Additionally or alternatively, the audio interface 1826 may include any equivalent electrical serial bus interface that can be used to connect digital audio devices to each other and / or to communicate audio data between integrated circuits in electronic devices. The audio interface 1826 may include an audio sampling queue 1827. The audio sampling queue 1827 may be any suitable memory device configured to temporarily store audio samples acquired by the input device 1805. Preferably, the audio sampling queue 1827 may include a buffer or cache. The audio sampling queue 1827 may include memory separate from that of the processor 1820. Alternatively, the audio sampling queue 1827 may include part or a subset of the memory of the processor 1820.

[0092] Counter 1828 may be any suitable counter. Counter 1828 may be configured to increment, for example, in response to the reception of an audio sample. Additionally or alternatively, counter 1828 may increment in response to the reception of an audio sample event. Counter 1828 may be reset (i.e., set to zero ("0")), for example, in response to or immediately after the reception of a synchronization signal from receiver 103. In some examples, counter 1828 may be one or more registers of processor 1820.

[0093] The DAC1830 may be configured to convert one or more digital audio samples into one or more analog audio samples before sending them to the receiver 103. In some embodiments, the DAC1830 may receive one or more digital audio samples from the audio sampling queue 1827. The DAC1830 may compress the digital audio samples (e.g., digital PCM samples) into a compressed format using, for example, a transcoder function (e.g., a codec) or an encoder. The DAC1830 may then convert one or more digital audio samples (e.g., compressed digital audio samples) into one or more analog audio samples. In further embodiments, the DAC1830 may be embedded in the I / O unit 1832. One or more analog audio samples may then be sent to the receiver 103, for example, via the I / O unit 1832.

[0094] I / O unit 1832 may be a radio embedded in processor 1820 that modulates and / or transmits packets containing data to audio sampling queue 1827. I / O unit 1832 may be configured to exchange data with one or more devices, including, for example, receiver 103. I / O unit 1832 may be a wireless network interface. I / O unit 1832 may be configured to wirelessly transmit audio data according to the techniques and / or processes described herein. Additionally, I / O unit 1832 may be configured to receive synchronization signals from a master audio clock, such as master clock 1840 (described in detail below). I / O unit 1832 may include a 2.4 GHz transceiver capable of supporting multiple wireless standards, such as BLE, IEEE 802.15.4, and / or proprietary wireless standards.

[0095] Receiver 103 may be configured to receive audio data from one or more transmitters. Receiver 103 may further be configured to combine audio data to generate (create) one or more audio files. Receiver 103 may play back one or more audio files. Additionally or alternatively, receiver 103 may store one or more audio files in, for example, a computing device 1870, for editing and / or playback purposes. As shown in Figure 18, receiver 103 includes a master clock 1840 and a processor 1850. It is understood that receiver 103 may include additional or fewer components beyond the scope of this disclosure.

[0096] The master clock 1840 may be an oscillator configured to generate a clock frequency for audio applications. The clock 1840 may be any suitable oscillator capable of generating a frequency of 32 MHz for audio peripherals and / or audio applications.

[0097] Processor 1850 may be similar to processor 1820 described above; that is, processor 1850 may be configured to perform (execute) one or more audio applications. Additionally, processor 1850 may be a SOC or ASIC. Processor 1850 may include hardware register 1852, timer 1854, receive queue 1856, analog-to-digital converter (ADC) 1858, and / or I / O unit 1860. Processor 1850 may include additional or fewer components such as an audio decoder (not shown). The audio decoder may accurately reproduce audio samples received from transmitter 101. Hardware register 1852, like hardware register 1822, may be any suitable register associated with processor 1850. Timer 1854 may be configured to perform time intervals. I / O unit 1860 may be a radio embedded in processor 1850 that demodulates and / or receives packets from one or more devices such as transmitter 101. I / O unit 1860 may be a wireless network interface configured to wirelessly receive audio data from one or more transmitters and send synchronization signals to one or more transmitters at predetermined intervals (e.g., 10 to 20 milliseconds). Similar to I / O unit 1832, I / O unit 1860 may include a 2.4 GHz transceiver capable of supporting multiple wireless standards such as BLE, IEEE 802.15.4, and / or proprietary wireless standards. ADC 1856 may be configured to convert one or more analog audio samples received from transmitter 101 into one or more digital audio samples. ADC 1858 may receive one or more analog audio samples from I / O unit 1860. I / O 1860 may convert one or more analog audio samples into one or more digital audio samples. I / O 1860 may decompress digital audio samples (e.g., digital PCM samples) into a decompressed format, for example, using a reverse transcoder function (e.g., a codec) or decoder.In some examples, the ADC 1858 may be embedded in the I / O unit 1860 to convert analog radio signals received from the transmitter 101 back into digital data. One or more digital audio samples may then be stored in a receive queue 1856 for additional and / or further processing. The receive queue 1856 may be configured to receive one or more audio samples from one or more transmitters. This reception occurs after the one or more audio samples have been received via the I / O unit 1860 and / or transformed using the ADC 1858. Preferably, the receive queue 1856 may include a buffer or cache. In some examples, the receive queue 1856 may send (transmit) one or more audio samples to a computing device 1870.

[0098] The computing device 1870 may be communicatively coupled to the receiver 103. In this regard, the computing device 1870 may be configured to receive one or more audio samples from the receiver 103 and to generate one or more audio files from the one or more audio samples. Additionally or alternatively, the computing device 1870 may be configured to receive one or more audio files from the receiver 103. The computing device 1870 may be a mobile device such as a cellular telephone, mobile phone, smartphone, tablet, laptop, or equivalent. Additionally or alternatively, the computing device 1870 may be a desktop computer, laptop computer, or alternatively a virtual computer. In some embodiments, the computing device 1870 may include a server such as a standalone server, an enterprise server, a server located in a server farm or cloud computing environment, and / or a virtual server hosted on hardware capable of supporting multiple virtual servers. In some embodiments, the computing device 1870 may be an audio mixer or mixing console configured to mix one or more audio samples.

[0099] The computing device 1870 may include memory 1880 for storing one or more audio samples and / or one or more audio files. Memory 1880 may include volatile and / or non-volatile, removable and / or non-removable media implemented in any method or technique for storing information such as computer-readable instructions, data structures, program modules, or other data. Memory 1880 may include one or more physical persistent memory devices and / or one or more non-persistent memory devices. Memory 1880 may include random access memory (RAM), read-only memory (ROM), electronically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, optical disc storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other media used to store desired information and accessible by the computing device 1870. In some embodiments, memory 1880 may include databases such as relational databases, hierarchical databases, distributed databases, in-memory databases, flat file databases, XML databases, NoSQL databases, graph databases, and / or any combination thereof.

[0100] The following paragraphs describe examples of implementations that may be carried out in accordance with this disclosure.

[0101] [Clause 1] A transmitter comprising an audio clock, one or more processors, and a memory for storing instructions, wherein, when executed by the one or more processors, the instructions cause the transmitter to receive a synchronization signal from a receiver, determine the difference between a counter value indicating a first amount of received audio samples and a predicted counter value based on the synchronization signal, and adjust the audio clock based on the difference between the counter value indicating a first amount of received audio samples and the predicted counter value.

[0102] [Clause 2] The transmitter is the transmitter of Clause 1, which includes at least one of a wireless microphone or a lavalier microphone.

[0103] [Clause 3] A transmitter according to either Clause 1 or 2, which, when executed by one or more processors, causes the transmitter to store the address field of the synchronization signal.

[0104] [Clause 4] The transmitter of Clause 3, wherein storing the address field of the synchronization signal includes storing the address field in a hardware register.

[0105] [Clause 5] The transmitter of Clause 3, which, when executed by one or more processors, causes the transmitter to generate an interrupt in response to having stored the address field of the synchronization signal.

[0106] [Clause 6] A transmitter under any one of Clauses 1 to 5, wherein adjusting the audio clock includes at least one of increasing the rate at which the microphone acquires an audio sample or decreasing the rate at which the microphone acquires an audio sample.

[0107] [Clause 7] The transmitter under any one of Clauses 1 to 6, which includes adjusting the audio clock, including adjusting the frame boundaries.

[0108] [Clause 8] A transmitter according to any one of Clauses 1 to 7, wherein, when the instruction is executed by one or more processors, the transmitter causes the transmitter to transfer a certain number of audio samples from an audio sampling queue to a transmission queue, and the receiver to send the certain number of audio samples to the receiver at a second predetermined interval.

[0109] [Clause 9] The transmitter of Clause 8, further comprising an analog-to-digital converter (ADC) configured to convert digital audio samples into analog audio samples before being sent to the receiver.

[0110] [Clause 10] The predictive counter value is based on a second amount of audio samples received between preceding synchronization signals, for a transmitter under any one of Clauses 1 to 9.

[0111] [Clause 11] The predicted counter value is based on the amount of audio samples configured by the receiver, according to any one of Clauses 1 to 10.

[0112] [Clause 12] A system comprising a receiver configured to transmit a synchronization signal at predetermined intervals, and a transmitter, wherein the transmitter is configured to receive the synchronization signal from the receiver, to determine the difference between a counter value indicating a first amount of received audio samples and a predicted counter value in response to receiving the synchronization signal, and to adjust the audio clock of the transmitter based on the counter indicating the first amount of received audio samples and the predicted counter value.

[0113] [Clause 13] The receiver is a system of Clause 12, which includes at least one of a wireless receiver, a mobile device, a smartphone, a tablet, or a laptop.

[0114] [Clause 14] The transmitter is a system according to either Clause 12 or 13, comprising at least one of a wireless microphone or a lavalier microphone.

[0115] [Clause 15] The system of any one of Clauses 12 to 14, wherein the transmitter is further configured to store the address field of the synchronization signal.

[0116] [Clause 16] The system of Clause 15, wherein the address field is stored in the hardware register of the transmitter.

[0117] [Clause 17] The system of Clause 15, wherein the transmitter is further configured to generate an interrupt in response to having stored the address field of the synchronization signal.

[0118] [Clause 18] The system of any one of Clauses 12 to 17, further comprising a second transmitter, the second transmitter configured to receive the synchronization signal from the receiver, determine a second difference between a second counter value indicating a second amount of received audio samples and a second predicted counter value in response to receiving the synchronization signal, and adjust a second audio clock of the second transmitter based on the difference between the second counter value indicating a second amount of received audio samples and the second predicted counter value.

[0119] [Clause 19] A system of any one of Clauses 12 to 18, wherein adjusting the audio clock of the transmitter includes at least one of increasing the rate at which the transmitter acquires an audio sample or decreasing the rate at which the transmitter acquires an audio sample.

[0120] [Clause 20] The system of any one of Clauses 12 to 19, in which adjusting the audio clock of the transmitter includes adjusting the frame boundaries.

[0121] [Clause 21] The system according to any one of Clauses 12 to 20, wherein the transmitter is further configured to transfer a certain number of audio samples from an audio sampling queue to a transmission queue and to send the certain number of audio samples to the receiver at a second predetermined interval.

[0122] [Clause 22] The transmitter is a system of Clause 21, including a digital-to-analog converter (DAC) that converts digital audio samples to analog audio samples.

[0123] [Clause 23] The receiver is part of the system of Clause 22, including an analog-to-digital converter (ADC) that converts the analog audio sample into a second digital audio sample.

[0124] [Clause 24] The system of any one of Clauses 12 to 23, wherein the predicted counter value is based on at least one of a second amount of audio samples received between preceding synchronization signals, or an amount of audio samples configured by the receiver.

[0125] [Clause 25] A method comprising: a transmitter receiving a synchronization signal from a receiver; in response to receiving the synchronization signal, the transmitter determining the difference between a counter value indicating a first amount of received audio samples and a predicted counter value; and the transmitter adjusting an audio clock based on the difference between the counter value indicating a first amount of received audio samples and the predicted counter value.

[0126] [Clause 26] The transmitter includes at least one of a wireless microphone or a lavalier microphone, in the manner of Clause 25.

[0127] [Clause 27] The receiver includes at least one of a wireless receiver, a mobile device, a smartphone, a tablet, or a laptop, in the manner of any one of Clauses 25 or 26.

[0128] [Clause 28] The method of any one of Clauses 25 to 27, further comprising the transmitter storing the address field of the synchronization signal.

[0129] [Clause 29] The address field of the synchronization signal is stored in a hardware register, in the manner of Clause 28.

[0130] [Clause 30] The method of Clause 28, further comprising generating an interrupt in response to having stored the address field of the synchronization signal.

[0131] [Clause 31] The method of adjusting the audio clock, which includes at least one of the following: the transmitter increasing the rate at which the microphone acquires audio samples, or the transmitter decreasing the rate at which the microphone acquires audio samples.

[0132] [Clause 32] Adjusting the audio clock is the method of any one of Clauses 25 to 31, including adjusting the frame boundary.

[0133] [Clause 33] The method of any one of Clauses 25 to 32, further comprising the transmitter transferring a certain number of audio samples from an audio sampling queue to a transmission queue, and the transmitter sending the certain number of audio samples to the receiver at a second predetermined interval.

[0134] [Clause 34] The method of Clause 33, further comprising the transmitter using a digital-to-analog converter (DAC) to convert the audio sample into an analog audio sample before sending the audio sample to the receiver.

[0135] [Clause 35] The predictive counter value is determined by the method of any one of Clauses 25 to 34, based on at least one of a second amount of audio samples received between preceding synchronization signals, or an amount of audio samples configured by the receiver.

[0136] [Clause 36] Non-temporary computer-readable medium including instructions, wherein, when executed, the instructions cause a transmitter to receive a synchronization signal from a receiver, determine the difference between a counter value indicating a first amount of received audio samples and a predicted counter value in response to receiving the synchronization signal, and adjust an audio clock based on the difference between the counter value indicating the first amount of received audio samples and the predicted counter value.

[0137] [Clause 37] The transmitter is a non-temporary computer-readable medium as defined in Clause 36, including at least one of a wireless microphone or a lavalier microphone.

[0138] [Clause 38] The receiver is a non-transient computer-readable medium as defined in either Clause 36 or 37, including at least one of a wireless receiver, a mobile device, a smartphone, a tablet, or a laptop.

[0139] [Clause 39] The instruction, when executed, causes the transmitter to store the address field of the synchronization signal in a non-temporary computer-readable medium as defined in any one of Clauses 36 to 38.

[0140] [Clause 40] The address field of the synchronization signal is stored in a hardware register, a non-temporary computer-readable medium as in Clause 39.

[0141] [Clause 41] When the instruction is executed, it causes the transmitter to generate an interrupt in response to having stored the address field of the synchronization signal, the difference between the counter value representing a first amount of the received audio sample and the predicted counter value, in non-temporary computer-readable media of Clause 39.

[0142] [Clause 42] A non-temporary computer-readable medium under any one of Clauses 36 to 41, which, when executed, causes the transmitter to adjust the audio clock by increasing the rate at which the microphone acquires audio samples or decreasing the rate at which the microphone acquires audio samples.

[0143] [Clause 43] The instruction, when executed, causes the transmitter to adjust the audio clock by adjusting the frame boundary, in any one of Clauses 36 to 42, in a non-temporary computer-readable medium.

[0144] [Clause 44] A non-temporary computer-readable medium under any one of Clauses 36 to 43, wherein the instruction, when executed, causes the transmitter to transfer a certain number of audio samples from an audio sampling queue to a transmission queue, and causes the receiver to send the certain number of audio samples to the receiver at a second predetermined interval.

[0145] [Clause 45] The instruction, when executed, causes the transmitter to convert the digital audio sample into an analog audio sample before sending the audio sample to the receiver, in a non-transient computer-readable medium as in Clause 44.

[0146] [Clause 46] The non-temporary computer-readable medium of Clause 44, wherein the instruction, when executed, causes the transmitter to determine the predicted counter value based on at least one of a second amount of audio samples received between preceding synchronization signals, or an amount of audio samples composed by the receiver.

[0147] While several examples have been described above, the features and / or steps of these examples may be combined, divided, omitted, rearranged, revised, and / or enhanced in any desired manner. Various modifications, alterations, and improvements will readily come to mind for those skilled in the art. Such modifications, alterations, and improvements, even if not expressly described herein, are intended to be part of this specification and within the gist and scope of this disclosure. Accordingly, the foregoing description is merely an example and not limiting.

Claims

1. It is a method, The microphone's wireless transmitter wirelessly transmits first audio data related to analog audio via a wireless network interface and using a first wireless communication protocol including Bluetooth® Low Energy (BLE), The wireless transmitter wirelessly transmits second audio data related to analog audio via the wireless network interface and using a second wireless communication protocol different from the first wireless communication protocol. Methods that include...

2. The method of claim 1, wherein the second wireless communication protocol includes a non-Bluetooth proprietary 2.4 GHz wireless communication protocol.

3. The aforementioned microphone, via the antenna, Transmission using the first wireless communication protocol via the antenna, Transmission using the second wireless communication protocol via the antenna and The method of claim 1, further comprising switching between the two.

4. The method of claim 3, wherein the transmission using the second wireless communication protocol via the antenna is after synchronization with a wireless device that receives the second audio data relating to analog audio.

5. The method of claim 1, further comprising the microphone generating at least one timestamp based on an indication received from a wireless device and based on the microphone's local clock.

6. The further includes receiving an indication based on the communication delay between the microphone and the wireless device via the wireless receiver of the microphone, The method of claim 5, wherein the second audio data includes at least one timestamp.

7. It is a microphone, Wireless transmitter and One or more processors, The memory that stores the instructions and Includes, The instruction, when executed by the one or more processors, configures the wireless transmitter to perform one or more of the methods of claims 1 to 6, the microphone.

8. A computer-readable medium that stores instructions, The instruction, when executed, configures the microphone to perform one or more of the methods of claims 1 to 6, in a computer storage medium.

9. It is a system, A microphone including a wireless transmitter, configured to perform one or more methods of claims 1 to 6, A first wireless device including a first wireless receiver, wherein the first wireless receiver is configured to wirelessly receive the first audio data using the first wireless communication protocol, A second wireless device including a second wireless receiver, wherein the second wireless receiver is configured to wirelessly receive the second audio data using the second wireless communication protocol. A system that includes this.

10. The system of claim 9, wherein the first wireless device includes a telephone, a tablet computer, or a laptop computer.

11. Further including a second microphone which includes a second wireless transmitter, The second microphone is, The third audio data is transmitted wirelessly via the second wireless network interface of the second wireless transmitter and using the first wireless communication protocol. The fourth audio data is to be transmitted wirelessly via the second wireless network interface and using the second wireless communication protocol. It is configured to do the following: The system of claim 9, wherein the microphone and the second microphone are each configured to synchronize with the first wireless device and the second wireless device.

12. The system of claim 9, wherein the second wireless device includes a universal serial bus (USB) connection configured to output an audio signal based on the second audio data.

13. The second wireless device includes a wireless transmitter, The second wireless device is configured to determine the communication delay between the second wireless receiver and the microphone. The wireless transmitter of the second wireless device is configured to transmit an indication based on the communication delay. The system of claim 9, wherein the second audio data includes at least one timestamp based on the indication received from the second wireless device.

14. The second wireless device further includes a local clock, The second wireless device is Wirelessly transmitting one or more data packets, each containing an indication based on the local clock, Receiving one or more responses corresponding to one or more data packets wirelessly from the microphone, The communication delay is determined based on the one or more responses and the local clock. The system of claim 13, configured to perform the following:

15. The second wireless device is One or more processors, The memory that stores the instructions and Includes, The system of claim 9, wherein the instruction, when executed by the one or more processors, configures the second wireless device to decode the received second audio data.

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