A wireless microphone low battery voice alert method and system

Abstract

This invention provides a method and system for providing low battery voice warnings for wireless microphones. The method includes: an identification step: each microphone is uniquely identified by its Bluetooth MAC address or a custom device ID; a detection step: each microphone monitors its own battery voltage in real time; a sending step: the microphone sends a warning command to its paired speaker via a Bluetooth link; a receiving step: the speaker receives the warning command from the connected microphone and parses it to obtain the microphone's identification and voltage; a judgment step: the speaker determines the number of microphones that have received the warning command within a preset time window. If the number of microphones is single, the speaker directly plays a prompt voice including the microphone number; if the number of microphones is multiple, a queue broadcast step is executed; a queue broadcast step: the warning command is stored in a priority queue and sorted from low to high according to the current battery voltage value of each microphone. The beneficial effects of this invention are: orderly broadcasting from multiple microphones avoids conflicts, and the warning is reliable and not disruptive.

Description

Technical Field

[0001] This invention relates to the field of intelligent audio device technology, and in particular to a method and system for providing low battery voice warnings for wireless microphones. Background Technology

[0002] In recent years, party speakers with wireless microphones have become increasingly popular, allowing users to sing or speak using wireless microphones at home gatherings, outdoor activities, karaoke sessions, and other settings. Currently, wireless microphones and speakers typically communicate via Bluetooth or 2.4GHz wireless communication technology for audio transmission.

[0003] However, when the battery of a wireless microphone gradually depletes to the point where it can no longer function properly, the microphone often suddenly loses power, causing the user to lose sound without any warning, severely impacting the user experience. Some high-end microphones have LED indicator lights or buzzers on the microphone itself to indicate low battery, but during actual singing, users are focused on the singing or music and are unlikely to notice the microphone's indicators in time, resulting in the problem not being detected promptly.

[0004] Therefore, it is necessary to propose a technical solution that can issue a warning in a way that is easily perceived by the user before the microphone battery is about to run out.

[0005] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] To address the lack of effective and intuitive early warning for low battery wireless microphones in existing technologies, this invention provides a low battery warning method for wireless microphones, comprising: Identification steps: Each microphone is uniquely identified by its Bluetooth MAC address or a custom device ID; Detection steps: Each microphone monitors its own battery voltage in real time. When the battery voltage is greater than a second preset threshold and less than or equal to a first preset threshold, a first warning instruction containing its unique identifier is generated; when the battery voltage is less than or equal to a second preset threshold, a second warning instruction containing its unique identifier is generated; the first preset threshold is greater than the second preset threshold. Sending steps: The microphone sends the warning command to the paired speaker via Bluetooth link; Receiving steps: The speaker receives the warning command from the connected microphone, parses and obtains the microphone's identifier and voltage, and assigns a broadcast number to each microphone. The broadcast number is used to distinguish different microphones during broadcast. Judgment steps: The speaker determines the number of microphones that received the warning command within the preset time window. If the number of microphones is a single microphone, the speaker directly plays a prompt voice including the microphone number. If the number of microphones is multiple microphones, the queue broadcast step is executed. Queue broadcasting steps: Store the warning instructions in a priority queue and sort them from low to high according to the current battery voltage value of each microphone. If the voltage is the same, sort them according to the trigger time. The speaker adopts a non-preemptive mode, and takes out the warning instructions from the queue in turn, and broadcasts the prompt voice containing the corresponding microphone number.

[0007] As a further improvement of the present invention, a priority arbitration step is also included. When the microphone needs to send both an audio data stream and a warning command simultaneously, a four-level priority arbitration mechanism is adopted: P0 level: Emergency warning command, triggered when the microphone battery voltage is less than or equal to the second preset threshold, immediately preempts bandwidth and suspends all other ongoing transmission tasks; P1 Level: First warning command, triggered when the microphone battery voltage is greater than the second preset threshold and less than or equal to the first preset threshold, and the warning command is inserted immediately after the current A2DP audio frame transmission is completed. P2 level: A2DP audio data stream transmission, continuous, can be interrupted by P0 or P1 level tasks. P3 level: Background tasks, including power monitoring and status polling, triggered periodically, and executed only when the Bluetooth link is idle.

[0008] As a further improvement of the present invention, an exception handling step is also included: After the microphone sends a warning command, it automatically starts a timer and waits for an ACK confirmation signal from the speaker. If an ACK is received before the timer expires, the transmission is confirmed to be successful. If no ACK is received before the timer expires, the warning command is retransmitted and the timer is reset until the number of retransmissions reaches a preset threshold N. If no ACK is received after N retransmissions, the microphone activates a local backup prompt.

[0009] As a further improvement of the present invention, a dynamic sampling step is also included, wherein the microphone dynamically adjusts the ADC sampling frequency and Bluetooth operating mode according to the current battery voltage range: First interval: When the battery voltage is greater than 3.0V, shallow monitoring mode is adopted, the ADC sampling frequency is 1 time / second, and Bluetooth is in low power sleep mode. Second interval: When the battery voltage is greater than 2.8V and less than or equal to 3.0V, a medium monitoring mode is adopted, the ADC sampling frequency is 2 times / second, and Bluetooth is in low power sleep mode; Third zone: When the battery voltage is greater than 2.6V and less than or equal to 2.8V, the altitude monitoring mode is adopted, the ADC sampling frequency is 10 times / second, and the Bluetooth connection remains active. Fourth zone: When the battery voltage is less than or equal to 2.6V, an emergency monitoring mode is adopted, the ADC continuously samples, and the Bluetooth connection remains active.

[0010] As a further improvement of the present invention, it also includes a broadcast timing management step, wherein the speaker adopts different broadcast strategies according to the priority of the warning command: First priority: When the speaker receives the P0 level warning command, a forced broadcast strategy is adopted to broadcast it immediately and reduce the current music volume during the broadcast of the warning voice. Second priority: When the speaker receives the P1 level warning command, it adopts an intelligent waiting strategy to detect whether the volume of the audio signal currently played by the speaker is lower than the preset volume threshold. If so, it is determined to be a music interval and the warning is played immediately; otherwise, it waits until the volume is lower than the preset volume threshold before playing the warning. Third priority: When the speaker receives a delay request sent by the user via button or App, a temporary suppression strategy is adopted to delay the warning broadcast for a preset time, and then rebroadcast it after the delay ends.

[0011] As a further improvement of the present invention, the detection step further includes anti-false positive processing, which includes at least one of the following: Time slot avoidance: Staggering the ADC sampling time with the microphone's RF transmission time slot; Median filtering: The median value of multiple consecutive ADC sample values ​​is taken as the effective voltage value; Moving average: Performs a moving average filter on multiple consecutive ADC sample values; Hysteresis Comparison: A hysteresis comparison mechanism is adopted to make the voltage threshold for triggering the microphone warning different from the voltage threshold for clearing the warning, and the voltage threshold for clearing the warning is higher than the voltage threshold for triggering the warning. De-jitter delay: After the microphone voltage is first detected to be lower than the first preset threshold, wait for the preset delay time, and then sample again to confirm after the delay ends; Transmit power compensation: Dynamically compensate the sampled voltage value based on the microphone's current RF transmit power, or adjust the warning trigger threshold accordingly.

[0012] This invention also discloses a low-battery voice warning system for a wireless microphone, comprising: at least one wireless microphone and one speaker. The wireless microphone includes: a pickup module, a first power module, a power detection module, a first main control module, and a first Bluetooth communication module. The first main control module is connected to the pickup module, the first power module, the power detection module, and the first Bluetooth communication module, respectively. The sound pickup module is used to collect the user's voice. The first power module is used to provide power to the wireless microphone. The power detection module is used to collect the voltage of the first power module in real time. The first main control module is used to generate a warning command containing the unique identifier of the microphone when the voltage is lower than a preset threshold. The first Bluetooth communication module is used to communicate bidirectionally with the speaker via the Bluetooth protocol. The bidirectional communication includes sending the warning command to the speaker and receiving feedback information returned by the speaker. The speaker includes a second main control module, a second Bluetooth communication module, and an audio output module. The second main control module is connected to the second power module, the second Bluetooth communication module, and the audio output module, respectively. The second main control module is configured as follows: Parse the received warning command to obtain the unique microphone identifier contained therein; Each microphone is assigned a broadcast number, which is used to distinguish different microphones during broadcasts; When only one microphone triggers the alarm, the audio output module is controlled to directly play a prompt voice containing the microphone number; When multiple microphones trigger the alarm simultaneously or sequentially, the received alarm commands are stored in a priority queue and sorted from low to high according to the current battery voltage of each microphone. If the voltages are the same, they are sorted according to the trigger time. The alarm commands are retrieved from the queue in a non-preemptive mode and the audio output module is controlled to play a prompt voice containing the corresponding microphone number. The second Bluetooth communication module is used to conduct bidirectional communication with the wireless microphone via the Bluetooth protocol. The bidirectional communication includes receiving the warning command sent by the wireless microphone and sending feedback information to the wireless microphone. The audio output module is used to play voice prompts and audio signals.

[0013] As a further improvement of the present invention, the first control module is further configured to: After the first Bluetooth communication module sends the warning command, a timer is started, and the system waits for the speaker to return a confirmation signal. If the confirmation signal is received before the timer expires, the transmission is confirmed to be successful; if the confirmation signal is not received after the timer expires, the first Bluetooth communication module is controlled to retransmit the warning command and reset the timer until the number of retransmissions reaches a preset threshold; if the confirmation signal is not received after the number of retransmissions reaches the preset threshold, a local backup prompt is activated. The first control module is also configured to: When the wireless microphone needs to send both audio data streams and warning commands simultaneously, a four-level priority arbitration mechanism is adopted: P0 level: Emergency warning command, triggered when the microphone battery voltage is less than or equal to the second preset threshold, immediately preempts bandwidth and suspends all other ongoing transmission tasks; P1 Level: First warning command, triggered when the microphone battery voltage is greater than the second preset threshold and less than or equal to the first preset threshold, and the warning command is inserted immediately after the current A2DP audio frame transmission is completed. P2 level: A2DP audio data stream transmission, continuous, can be interrupted by P0 or P1 level tasks. P3 level: Background tasks, including power monitoring and status polling, triggered periodically, and executed only when the Bluetooth link is idle; The power detection module is configured as follows: Dynamically adjust the ADC sampling frequency and Bluetooth operating mode based on the current battery voltage range: First interval: When the battery voltage is greater than 3.0V, shallow monitoring mode is adopted, the ADC sampling frequency is 1 time / second, and Bluetooth is in low power sleep mode. Second interval: When the battery voltage is greater than 2.8V and less than or equal to 3.0V, a medium monitoring mode is adopted, the ADC sampling frequency is 2 times / second, and Bluetooth is in low power sleep mode; Third zone: When the battery voltage is greater than 2.6V and less than or equal to 2.8V, the altitude monitoring mode is adopted, the ADC sampling frequency is 10 times / second, and the Bluetooth connection remains active. Fourth zone: When the battery voltage is less than or equal to 2.6V, an emergency monitoring mode is adopted, the ADC continuously samples, and the Bluetooth connection remains active; The second main control module is also configured as follows: Different broadcast strategies are adopted according to the priority of the warning instructions: First priority: When the speaker receives the P0 level warning command, a forced broadcast strategy is adopted to broadcast it immediately and reduce the current music volume during the broadcast of the warning voice. Second priority: When the speaker receives the P1 level warning command, it adopts an intelligent waiting strategy to detect whether the volume of the audio signal currently played by the speaker is lower than the preset volume threshold. If so, it is determined to be a music interval and the warning is played immediately; otherwise, it waits until the volume is lower than the preset volume threshold before playing the warning. Third priority: When the speaker receives a delay request sent by the user via button or App, a temporary suppression strategy is adopted to delay the warning broadcast for a preset time, and then rebroadcast it after the delay ends.

[0014] As a further improvement of the present invention, the power detection module further includes an anti-false judgment processing unit: the anti-false judgment unit is configured to perform at least one of the following operations: Time slot avoidance: Staggering the ADC sampling time with the microphone's RF transmission time slot; Median filtering: The median value of multiple consecutive ADC sample values ​​is taken as the effective voltage value; Moving average: Performs a moving average filter on multiple consecutive ADC sample values; Hysteresis Comparison: A hysteresis comparison mechanism is adopted to make the voltage threshold for triggering the microphone warning different from the voltage threshold for clearing the warning, and the voltage threshold for clearing the warning is higher than the voltage threshold for triggering the warning. De-jitter delay: After the microphone voltage is first detected to be lower than the first preset threshold, wait for the preset delay time, and then sample again to confirm after the delay ends; Transmit power compensation: Dynamically compensate the sampled voltage value based on the microphone's current RF transmit power, or adjust the warning trigger threshold accordingly.

[0015] As a further improvement of the present invention, the wireless microphone also includes a Bluetooth audio chip, which integrates the first main control module and the first Bluetooth communication module, and has a built-in analog-to-digital converter interface for collecting battery voltage; the model of the Bluetooth audio chip is AC7066D.

[0016] The beneficial effects of this invention are: 1. Ordered announcement of multiple microphones to avoid conflicts: When multiple microphones are low on power at the same time or in succession, the speaker uses a priority queue and non-preemptive order to announce the low power of microphone X in order of battery voltage, thus solving the conflict problem of multiple microphones competing for the same speaker output channel. 2. Reliable and non-disruptive alerts: Alert commands are sent separately from the audio stream via Bluetooth control channel, with retransmission and ACK confirmation mechanisms to ensure delivery; at the same time, the broadcast is differentiated according to the urgency level (mandatory broadcast for emergency alerts, music interval for initial alert detection, and temporary delay by the user), which ensures that the alerts are delivered while avoiding spoiling the mood during the climax of the party; 3. Anti-false alarm and low power consumption: Software methods such as time slot avoidance, median filtering, and jitter reduction delay are used to suppress false alarms caused by instantaneous voltage drops. The sampling frequency and Bluetooth working status are dynamically adjusted to balance monitoring accuracy and power consumption and extend microphone battery life.

[0017] 4. Low cost and practical: It utilizes the chip's existing resources (ADC, Bluetooth protocol stack extension, etc.) to achieve low battery detection and warning without the need for additional hardware. It provides users with intuitive voice prompts before the microphone is completely powered off, avoiding sudden silence during singing. It is suitable for scenarios such as home karaoke and parties. Attached Figure Description

[0018] Figure 1 This is an overall flowchart of the method of the present invention; Figure 2 This is a block diagram illustrating the principle of the priority arbitration mechanism of this invention; Figure 3 This is a schematic diagram of the data flow for the transmission and parsing of early warning commands in this invention; Figure 4 This is a schematic diagram of the Bluetooth wireless microphone circuit of the present invention; Figure 5 This is the circuit schematic diagram of the Bluetooth speaker of the present invention. Detailed Implementation

[0019] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0020] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0021] like Figure 1 As shown, this invention discloses a low battery voice warning method for wireless microphones, comprising: Identification process: Each microphone has a unique Bluetooth MAC address (or custom ID) when it leaves the factory. This identifier is stored in the microphone's control module and is used to distinguish different microphones in warning commands. Detection steps: Each microphone monitors its own battery voltage in real time. When the battery voltage is greater than the second preset threshold (2.6V) and less than or equal to the first preset threshold (2.8V), a first warning command containing its unique identifier is generated; when the battery voltage is less than or equal to the second preset threshold (2.6V), a second warning command containing its unique identifier is generated; the first preset threshold is greater than the second preset threshold. Sending steps: The wireless microphone sends the warning command to the paired speaker via Bluetooth link; Receiving steps: The speaker receives the warning command from the connected microphone and parses it to obtain the microphone's identifier and voltage. At the same time, the speaker assigns a broadcast number to each microphone, which is used to distinguish different microphones during broadcast. Judgment steps: The audio-visual end determines the number of microphones that received the warning command within the preset time window. If the number of microphones is a single microphone, the speaker directly plays a prompt voice including the microphone number, "Microphone number X has low battery, please charge it". If the number of microphones is multiple microphones, the queue broadcast step is executed. Queue announcement steps: Store the warning instructions in the priority queue, and sort them from low to high according to the current battery voltage values of each microphone. The lower the voltage, the higher the priority. If the voltages are the same, sort them according to the trigger time sequence. The speaker adopts a non-preemptive mode, and sequentially retrieves the warning instructions from the queue and announces the prompt voice containing the corresponding microphone number, "Microphone No. X has low battery, please charge", where X is the microphone number.

[0022] As Figure 2 shown, the present invention further includes a priority arbitration step. When the microphone needs to send an audio data stream and a warning instruction simultaneously, a four-level priority arbitration mechanism is adopted: P0 level: Emergency warning instruction (the second warning instruction), triggered when the microphone battery voltage is less than or equal to the second preset threshold (≤2.6V), immediately preempts the bandwidth, and suspends all other ongoing transmission tasks; P1 level: First warning instruction (the first warning instruction), triggered when the microphone battery voltage is greater than the second preset threshold and less than or equal to the first preset threshold (2.6V < Vbat ≤ 2.8V), and inserts the warning instruction immediately after waiting for the current A2DP audio frame transmission to complete; P2 level: A2DP audio data stream transmission, which continues and can be interrupted by P0 level or P1 level tasks; The P2 level task is the A2DP audio transmission with normal priority, which continues when there are no P0 / P1 tasks and can be interrupted by higher priority tasks. After being interrupted, the microphone will resume audio transmission after the warning instruction is sent. ]

[0023] P3 level: The P3 level task is the background operation with the lowest priority (such as power monitoring, status polling), which is triggered according to a preset period and is only executed when there are no higher priority tasks (P0 to P2) occupying the Bluetooth link. After execution, the link is released.

[0024] The present invention further includes an exception handling step: After the microphone sends a warning instruction, it automatically starts a timer and waits for the ACK confirmation signal returned by the speaker; If the ACK is received before the timer times out, it is confirmed that the transmission is successful; If the ACK is still not received when the timer times out, the warning instruction is retransmitted and the timer is reset until the number of retransmissions reaches the preset threshold N; If the ACK is still not received after retransmitting N times, the microphone starts a local standby prompt, and the local standby prompt includes fast flashing of the indicator light, etc.

[0025] The present invention further includes a dynamic sampling step. The microphone dynamically adjusts the ADC sampling frequency and Bluetooth working mode according to the current battery voltage range: The first range: When the battery voltage is greater than 3.0V, the shallow monitoring mode is adopted, the ADC sampling frequency is 1 time per second, the Bluetooth is in the low-power sleep state, the Bluetooth state is deep sleep (wakeable), and the power consumption < 100μA; Second range: When the battery voltage (Vbat) is greater than 2.8V and less than or equal to 3.0V, a medium monitoring mode is adopted, the ADC sampling frequency is 2 times / second, Bluetooth is in low power sleep mode, Bluetooth is in shallow sleep mode, and the power consumption is 200μA. Third zone: When the battery voltage is greater than 2.6V and less than or equal to 2.8V, the altitude monitoring mode is adopted, the ADC sampling frequency is 10 times / second, the Bluetooth connection remains active, and the power consumption is 1mA. Fourth range: When the battery voltage is less than or equal to 2.6V, an emergency monitoring mode is adopted, the ADC continuously samples, the Bluetooth connection remains active, and the power consumption is 5mA.

[0026] This invention also includes a broadcast timing management step, whereby the speaker adopts different broadcast strategies based on the priority of the warning command: First priority (highest): When the speaker receives a P0 level warning command, a forced broadcast strategy is adopted to broadcast it immediately and briefly reduce the current music volume during the broadcast of the warning voice. Second priority (medium): When the speaker receives a P1 level warning command, it adopts an intelligent waiting strategy to detect whether the volume of the audio signal currently played by the speaker is lower than the preset volume threshold. If so, it is determined to be a music interval and the warning is played immediately; otherwise, it waits until the volume is lower than the preset volume threshold before playing the warning. Third priority (low): When the speaker receives a delay request sent by the user via button or App, a temporary suppression strategy is adopted to delay the warning broadcast for a preset time (such as 30 seconds), and the broadcast will be restarted after the delay ends.

[0027] To avoid false alarms caused by a drop in battery voltage due to the instantaneous high current generated when the microphone transmits audio, this invention employs a variety of anti-false alarm processing methods.

[0028] Regarding the sampling timing, the second main control module can stagger the ADC sampling time with the microphone's RF transmission time slot (time slot avoidance) to avoid interference from the peak transmission current on the sampled value.

[0029] In terms of sample value processing, median filtering or moving average filtering can be used for multiple consecutive ADC sample values ​​to smooth the voltage curve and remove instantaneous spikes.

[0030] To prevent repeated triggering caused by voltage oscillations near the threshold, a hysteresis comparison mechanism can be used to make the voltage threshold for warning triggering different from the voltage threshold for warning clearing, and the clearing threshold higher than the triggering threshold.

[0031] Meanwhile, after the voltage is first detected to be below the preset threshold, a de-jittering delay can be performed (such as re-sampling after 20ms) to confirm that the voltage is indeed below the threshold and not a momentary fluctuation.

[0032] In addition, the sampling voltage value can be dynamically compensated based on the microphone's current RF transmission power, or the warning trigger threshold (transmission power compensation) can be adjusted accordingly to improve the accuracy of warnings in high-power transmission scenarios.

[0033] Those skilled in the art should understand that the above-mentioned anti-misjudgment measures can be used alone or in any combination, and the specific parameters (such as the number of consecutive samplings, the dejittering time, the hysteresis offset, etc.) can be adjusted according to actual needs without affecting the core inventive concept of this invention.

[0034] In this invention, the speaker assigns a broadcast number (e.g., 1, 2, 3) to each microphone. This number is used to distinguish different microphones during voice broadcasting. The assignment rule can be one of the following methods: The microphones are automatically assigned numbers based on the order in which they establish Bluetooth connections with the speakers: the first connected microphone is number 1, the second is number 2, and so on. Alternatively, the microphones can be sorted by their Bluetooth MAC addresses from smallest to largest, and assigned numbers 1, 2, 3, and so on. Alternatively, users can customize the numbering via the speaker's app or buttons.

[0035] Those skilled in the art should understand that the above allocation rules are merely examples, and any method that can map a microphone's unique identifier to a user-identifiable number may be used.

[0036] This invention also discloses a low-battery voice warning system for a wireless microphone, comprising: at least one wireless microphone and one speaker, such as... Figure 4 As shown, the wireless microphone includes: a pickup module, a first power module, a power detection module, a first main control module, and a first Bluetooth communication module. The first main control module is connected to the pickup module, the first power module, the power detection module, and the first Bluetooth communication module. Sound pickup module: used to collect the user's voice; First power module: Used to provide power to the wireless microphone; Power detection module: used to collect the voltage of the first power supply module in real time; First main control module: used to generate an early warning command containing the unique identifier of the microphone when the voltage is lower than a preset threshold; First Bluetooth communication module: used for two-way communication with the speaker via Bluetooth protocol. Two-way communication includes sending warning commands to the speaker and receiving feedback information returned by the speaker. like Figure 5 As shown, the speaker includes a second main control module, a second Bluetooth communication module, and an audio output module. The second main control module is connected to the second power module, the second Bluetooth communication module, and the audio output module, respectively.

[0037] The second main control module is configured to: Analyze the received warning instruction and obtain the unique identifier of the microphone contained therein; Assign a broadcast number to each microphone, and the broadcast number is used to distinguish different microphones during broadcasting; When only one microphone triggers a warning, control the audio output module to directly broadcast the prompt voice containing the microphone number; When multiple microphones trigger warnings simultaneously or successively, store the received warning instructions in a priority queue, sort them from low to high according to the current battery voltage value of each microphone, and sort them in chronological order of trigger time when the voltages are the same, and adopt a non-preemptive mode to sequentially retrieve the warning instructions from the queue, and control the audio output module to broadcast the prompt voice containing the corresponding microphone number; The second Bluetooth communication module: is used to perform two-way communication with the wireless microphone through the Bluetooth protocol, and the two-way communication includes receiving the warning instruction sent by the wireless microphone and sending feedback information to the wireless microphone; The audio output module: is used to play voice prompts and audio signals.

[0038] The first main control module is also configured to: Start a timer after the first Bluetooth communication module sends the warning instruction and wait for the confirmation signal returned by the speaker; If the confirmation signal is received before the timer expires, it is confirmed that the transmission is successful; if the confirmation signal is not received after the timer expires, control the first Bluetooth communication module to retransmit the warning instruction and reset the timer until the number of retransmissions reaches the preset threshold; if the confirmation signal is not received after the number of retransmissions reaches the preset threshold, start the local standby prompt; The first main control module is also configured to: When the microphone needs to send audio data streams and warning instructions simultaneously, adopt a four-level priority arbitration mechanism: P0 level: Emergency warning instruction, triggered when the microphone battery voltage is less than or equal to the second preset threshold (≤2.6V), immediately preempt the bandwidth and suspend all other ongoing transmission tasks; P1 level: First warning instruction, triggered when the microphone battery voltage is greater than the second preset threshold and less than or equal to the first preset threshold (2.6V<Vbat≤2.8V), wait for the current A2DP audio frame transmission to complete and then immediately insert the warning instruction; ​​

[0039] P3 level: P3 level tasks are the lowest priority background operations (such as battery monitoring and status polling), which are triggered according to a preset cycle and are only executed when no higher priority tasks (P0~P2) occupy the Bluetooth link. After execution, the link is released.

[0040] The power detection module is configured as follows: Dynamically adjust the ADC sampling frequency and Bluetooth operating mode based on the current battery voltage range: First interval: When the battery voltage is greater than 3.0V, shallow monitoring mode is adopted, the ADC sampling frequency is 1 time / second, and Bluetooth is in low power sleep mode. Second interval: When the battery voltage is greater than 2.8V and less than or equal to 3.0V, a medium monitoring mode is adopted, the ADC sampling frequency is 2 times / second, and Bluetooth is in low power sleep mode; Third zone: When the battery voltage is greater than 2.6V and less than or equal to 2.8V, the altitude monitoring mode is adopted, the ADC sampling frequency is 10 times / second, and the Bluetooth connection remains active. Fourth zone: When the battery voltage is less than or equal to 2.6V, an emergency monitoring mode is adopted, the ADC continuously samples, and the Bluetooth connection remains active; The second main control module is also configured as follows: Different broadcast strategies are adopted according to the priority of the warning instructions: First priority: When the speaker receives a P0 level warning command, a forced broadcast strategy is adopted to broadcast it immediately and reduce the current music volume during the broadcast of the warning voice. Second priority: When the speaker receives a P1 level warning command, it adopts an intelligent waiting strategy to detect whether the volume of the audio signal currently played by the speaker is lower than the preset volume threshold. If so, it is determined to be a music interval and the warning is played immediately; otherwise, it waits until the volume is lower than the preset volume threshold before playing the warning. Third priority: When the speaker receives a delay request sent by the user via button or App, a temporary suppression strategy is adopted to delay the warning broadcast for a preset time, and then rebroadcast it after the delay ends.

[0041] The power detection module also includes an anti-false alarm processing unit, which is configured to perform at least one of the following operations: Time slot avoidance: Staggering the ADC sampling time with the microphone's RF transmission time slot; Median filtering: The median value of multiple consecutive ADC sample values ​​is taken as the effective voltage value; Moving average: Performs a moving average filter on multiple consecutive ADC sample values; Hysteresis Comparison: A hysteresis comparison mechanism is adopted to make the voltage threshold for triggering the microphone warning different from the voltage threshold for clearing the warning, and the voltage threshold for clearing the warning is higher than the voltage threshold for triggering the warning. De-jitter delay: After the microphone voltage is first detected to be lower than the first preset threshold, wait for the preset delay time, and then sample again to confirm after the delay ends; Transmit power compensation: Dynamically compensate the sampled voltage value based on the microphone's current RF transmit power, or adjust the warning trigger threshold accordingly.

[0042] The first power module includes a rechargeable battery.

[0043] The speaker unit integrates a Bluetooth 5.4 module as a secondary Bluetooth communication module, pairing with a wireless microphone that uses the JL AC7066D Bluetooth audio chip. The AC7066D chip's ADC pin is connected to the sampling point of the rechargeable battery's positive terminal via a resistor divider. The chip's built-in 32-bit DSP processor reads the ADC conversion result at a preset cycle and converts it into the battery voltage value. This chip supports Bluetooth audio protocols such as A2DP and HFP.

[0044] The AC7066D chip has a built-in ADC interface for real-time battery voltage acquisition. When the battery voltage is detected to be lower than a first preset threshold (e.g., 2.8V), the microphone control chip determines that the battery is in a low-battery state and then sends a custom low-battery warning command, such as the string "BAT_LOW_1", to the paired speaker through the chip's Bluetooth communication interface.

[0045] To ensure the real-time nature and reliability of the warning command, it is transmitted using the AT command channel in the HFP (Hands-Free Profile) configuration file supported by the chip. The HFP command channel is independent and separate from the A2DP audio stream channel that transmits the user's vocals. Therefore, even if the A2DP channel is under high audio transmission load, the warning command can still be sent immediately through the HFP command channel, unaffected by audio quality fluctuations or bandwidth usage, thus ensuring that the low battery warning is delivered to the speaker in a timely manner.

[0046] Speaker's response to the first low battery warning After the speaker receives a custom low-battery command (e.g., "BAT_LOW_1") from the microphone via the second Bluetooth communication module, the second main control module parses the command and identifies a low-battery event corresponding to a first preset threshold (2.8V). Subsequently, the second main control module reads a pre-stored MP3 audio file, "Microphone #X is low on battery, please charge," from the SPI Flash memory and transmits this audio data to the audio amplifier module, which then plays the voice prompt through the speaker. The audio output module includes the audio amplifier module and the speaker.

[0047] Triggering and broadcasting of emergency low battery warning When the microphone detects that the battery voltage continues to drop below a second preset threshold (e.g., 2.6V), it generates and sends another custom low-battery command, such as "BAT_LOW_2". Upon receiving this command, the speaker recognizes it as an emergency warning. The second main control module reads the corresponding MP3 audio file "Microphone battery is about to run out, please replace it as soon as possible" from the SPI Flash and outputs it to the speaker through the audio amplifier, issuing a more urgent reminder to the user.

[0048] As a further preferred embodiment of the present invention, in order to reduce the amount of data transmitted wirelessly and reduce the power consumption of the microphone, no voice content is stored inside the microphone. When the battery voltage is detected to be lower than a first preset threshold (e.g., 2.8V), the microphone sends only a short instruction code (e.g., 0x11) as a low battery warning instruction; when the voltage is lower than a second preset threshold (e.g., 2.6V), another instruction code (e.g., 0x12) is sent.

[0049] The speaker has pre-stored audio files (such as MP3 format) that correspond one-to-one with each command code. After the speaker receives the command code, the second main control module finds and reads the corresponding audio file according to the mapping relationship (for example, 0x11 corresponds to "microphone battery is low, please charge it in time", and 0x12 corresponds to "microphone battery is about to run out, please replace it as soon as possible"), and then outputs it to the speaker through the audio amplifier.

[0050] As a further preferred embodiment of the invention, when broadcasting voice prompts, the speaker can utilize the multi-band EQ configuration feature supported by the AC7066D chip to temporarily adjust the equalizer parameters, enhancing the clarity of the human voice frequency band and making the warning voice stand out more against the background music. After the broadcast is completed, the EQ parameters are restored to their original settings.

[0051] like Figure 3 As shown, the encapsulation and transmission of warning commands are a specific implementation method: When the microphone chip (AC7066D) detects that the battery voltage is ≤ 2.8V, its DSP encapsulates the warning information into a custom AT command string. This command uses a vendor-defined format allowed by the HFP (Hands-Free Profile) specification, for example: AT+VBATLOW=mic_id,voltage, where mic_id is the microphone's unique identifier (such as a Bluetooth MAC address or a custom device ID), and voltage is the current battery voltage value (in mV). As an example, if the microphone ID is 1 and the voltage is 2800mV, the command string is: AT+VBATLOW=1,2800. The microphone sends this custom AT command using the command channel (independent of the A2DP audio stream channel) established in the AC7066D chip's HFP connection. Because the command channel is separate from the audio channel, the warning command can be sent instantly even under high audio transmission load, unaffected by audio quality.

[0052] Bluetooth protocol stack callbacks on the speaker side for receiving and handling unrecognized commands: After the speaker's Bluetooth baseband receives the radio frequency signal, the data packet is transmitted upwards through the HCI layer, L2CAP layer, and RFCOMM layer in sequence, and finally delivered to the AT command parser in the HFP Profile.

[0053] The standard AT command parser matches the received string against the command list defined by the HFP specification (such as +CIEV, +VGS, etc.). Since AT+VBATLOW=1,2800 is not in the standard command list, the parser cannot recognize it. According to the HFP protocol, for unrecognized commands, the protocol stack does not discard them directly, but instead triggers an "unrecognized command" callback function.

[0054] In this embodiment, the callback function is HFP_UNRECOGNISE_AT_CMD_IND. Through this callback, the protocol stack reports the original, unmodified command string (e.g., "AT+VBATLOW=1,2800") to the speaker's application layer program.

[0055] Application-layer custom command parser: A custom command parser is pre-built in the speaker's application layer. This parser registers a list of command prefixes to be monitored, including "AT+VBATLOW". When the application layer receives a string from the callback function, it matches it against the command prefixes in sequence. Upon successful matching of "AT+VBATLOW", the parser further parses the string, extracting the microphone identifier (mic_id=1) and voltage value (voltage=2800). Subsequently, the parser passes the extracted parameters to the low battery warning service module.

[0056] Triggering the broadcast process: The warning module determines whether to broadcast the message "Microphone 1 has low battery, please charge" based on the microphone identifier (microphone 1) and voltage value (2.8V). The speaker then executes the corresponding broadcast process, including waiting for a music break and performing a ducking operation.

[0057] Through the above mechanism, even if the microphone sends a custom AT command, the speaker can accurately identify and trigger the warning broadcast, thus realizing the reliable transmission and parsing of the warning command.

[0058] The warning command is encapsulated in a custom AT command format and sent through the command channel of the Bluetooth HFP protocol. The speaker reports the custom AT command to the application layer through the unrecognized command callback mechanism of the protocol stack, and the parameters are extracted by the custom command parser.

[0059] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for providing a low battery voice warning for a wireless microphone, characterized in that, include: Identification steps: Each microphone is uniquely identified by its Bluetooth MAC address or a custom device ID; Detection steps: Each microphone monitors its own battery voltage in real time. When the battery voltage is greater than a second preset threshold and less than or equal to a first preset threshold, a first warning instruction containing its unique identifier is generated; when the battery voltage is less than or equal to a second preset threshold, a second warning instruction containing its unique identifier is generated; the first preset threshold is greater than the second preset threshold. Sending steps: The microphone sends the warning command to the paired speaker via Bluetooth link; Receiving steps: The speaker receives the warning command from the connected microphone, parses and obtains the microphone's identifier and voltage, and assigns a broadcast number to each microphone. The broadcast number is used to distinguish different microphones during broadcast. Judgment steps: The speaker determines the number of microphones that received the warning command within the preset time window. If the number of microphones is a single microphone, the speaker directly plays a prompt voice including the microphone number. If the number of microphones is multiple microphones, the queue broadcast step is executed. Queue broadcasting steps: Store the warning instructions in a priority queue and sort them from low to high according to the current battery voltage value of each microphone. If the voltage is the same, sort them according to the trigger time. The speaker adopts a non-preemptive mode, and takes out the warning instructions from the queue in turn, and broadcasts the prompt voice containing the corresponding microphone number.

2. The low battery voice warning method according to claim 1, characterized in that, It also includes a priority arbitration step, employing a four-level priority arbitration mechanism when the microphone needs to send both audio data streams and warning commands simultaneously: P0 level: Emergency warning command, triggered when the microphone battery voltage is less than or equal to the second preset threshold, immediately preempts bandwidth and suspends all other ongoing transmission tasks; P1 Level: First warning command, triggered when the microphone battery voltage is greater than the second preset threshold and less than or equal to the first preset threshold, and the warning command is inserted immediately after the current A2DP audio frame transmission is completed. P2 level: A2DP audio data stream transmission, continuous, can be interrupted by P0 or P1 level tasks. P3 level: Background tasks, including power monitoring and status polling, triggered periodically, and executed only when the Bluetooth link is idle.

3. The low battery voice warning method according to claim 1, characterized in that, It also includes exception handling steps: After the microphone sends a warning command, it automatically starts a timer to wait for an ACK confirmation signal from the speaker; if an ACK is received before the timer expires, the transmission is confirmed to be successful. If no ACK is received after the timer expires, the warning instruction is retransmitted and the timer is reset until the number of retransmissions reaches a preset threshold N; if no ACK is received after N retransmissions, the microphone activates a local backup prompt.

4. The low battery voice warning method according to claim 1, characterized in that, It also includes a dynamic sampling step, in which the microphone dynamically adjusts the ADC sampling frequency and Bluetooth operating mode according to the current battery voltage range: First interval: When the battery voltage is greater than 3.0V, shallow monitoring mode is adopted, the ADC sampling frequency is 1 time / second, and Bluetooth is in low power sleep mode. Second interval: When the battery voltage is greater than 2.8V and less than or equal to 3.0V, a medium monitoring mode is adopted, the ADC sampling frequency is 2 times / second, and Bluetooth is in low power sleep mode; Third zone: When the battery voltage is greater than 2.6V and less than or equal to 2.8V, the altitude monitoring mode is adopted, the ADC sampling frequency is 10 times / second, and the Bluetooth connection remains active. Fourth zone: When the battery voltage is less than or equal to 2.6V, an emergency monitoring mode is adopted, the ADC continuously samples, and the Bluetooth connection remains active.

5. The low battery voice warning method according to claim 2, characterized in that, It also includes a broadcast timing management step, in which the speaker adopts different broadcast strategies based on the priority of the warning command: First priority: When the speaker receives the P0 level warning command, a forced broadcast strategy is adopted to broadcast it immediately and reduce the current music volume during the broadcast of the warning voice. Second priority: When the speaker receives the P1 level warning command, it adopts an intelligent waiting strategy to detect whether the volume of the audio signal currently played by the speaker is lower than the preset volume threshold. If so, it is determined to be a music interval and the warning is played immediately; otherwise, it waits until the volume is lower than the preset volume threshold before playing the warning. Third priority: When the speaker receives a delay request sent by the user via button or App, a temporary suppression strategy is adopted to delay the warning broadcast for a preset time, and then rebroadcast it after the delay ends.

6. The low battery voice warning method according to claim 2, characterized in that, The detection step further includes anti-false positive processing, which includes at least one of the following: Time slot avoidance: Staggering the ADC sampling time with the microphone's RF transmission time slot; Median filtering: The median value of multiple consecutive ADC sample values ​​is taken as the effective voltage value; Moving average: Performs a moving average filter on multiple consecutive ADC sample values; Hysteresis Comparison: A hysteresis comparison mechanism is adopted to make the voltage threshold for triggering the microphone warning different from the voltage threshold for clearing the warning, and the voltage threshold for clearing the warning is higher than the voltage threshold for triggering the warning. De-jitter delay: After the microphone voltage is first detected to be lower than the first preset threshold, wait for the preset delay time, and then sample again to confirm after the delay ends; Transmit power compensation: Dynamically compensate the sampled voltage value based on the microphone's current RF transmit power, or adjust the warning trigger threshold accordingly.

7. A low battery voice warning system for a wireless microphone, characterized in that, include: At least one wireless microphone and one speaker are provided. The wireless microphone includes: a pickup module, a first power module, a power detection module, a first main control module, and a first Bluetooth communication module. The first main control module is connected to the pickup module, the first power module, the power detection module, and the first Bluetooth communication module, respectively. The sound pickup module is used to collect the user's voice. The first power module is used to provide power to the wireless microphone. The power detection module is used to collect the voltage of the first power module in real time. The first main control module is used to generate a warning command containing the unique identifier of the microphone when the voltage is lower than a preset threshold. The first Bluetooth communication module is used to communicate bidirectionally with the speaker via the Bluetooth protocol. The bidirectional communication includes sending the warning command to the speaker and receiving feedback information returned by the speaker. The speaker includes a second main control module, a second Bluetooth communication module, and an audio output module. The second main control module is connected to the second power module, the second Bluetooth communication module, and the audio output module, respectively. The second main control module is configured as follows: Parse the received warning command to obtain the unique microphone identifier contained therein; Each microphone is assigned a broadcast number, which is used to distinguish different microphones during broadcasts; When only one microphone triggers the alarm, the audio output module is controlled to directly play a prompt voice containing the microphone number; When multiple microphones trigger the alarm simultaneously or sequentially, the received alarm commands are stored in a priority queue and sorted from low to high according to the current battery voltage of each microphone. If the voltages are the same, they are sorted according to the trigger time. The alarm commands are retrieved from the queue in a non-preemptive mode and the audio output module is controlled to play a prompt voice containing the corresponding microphone number. The second Bluetooth communication module is used to conduct bidirectional communication with the wireless microphone via the Bluetooth protocol. The bidirectional communication includes receiving the warning command sent by the wireless microphone and sending feedback information to the wireless microphone. The audio output module is used to play voice prompts and audio signals.

8. The low battery voice warning system according to claim 7, characterized in that, The first control module is also configured to: After the first Bluetooth communication module sends the warning command, a timer is started, and the system waits for the speaker to return a confirmation signal. If the confirmation signal is received before the timer expires, the transmission is confirmed to be successful; if the confirmation signal is not received after the timer expires, the first Bluetooth communication module is controlled to retransmit the warning command and reset the timer until the number of retransmissions reaches a preset threshold; if the confirmation signal is not received after the number of retransmissions reaches the preset threshold, a local backup prompt is activated. The first control module is also configured to: When the wireless microphone needs to send both audio data streams and warning commands simultaneously, a four-level priority arbitration mechanism is adopted: P0 level: Emergency warning command, triggered when the microphone battery voltage is less than or equal to the second preset threshold, immediately preempts bandwidth and suspends all other ongoing transmission tasks; P1 Level: First warning command, triggered when the microphone battery voltage is greater than the second preset threshold and less than or equal to the first preset threshold, and the warning command is inserted immediately after the current A2DP audio frame transmission is completed. P2 level: A2DP audio data stream transmission, continuous, can be interrupted by P0 or P1 level tasks. P3 level: Background tasks, including power monitoring and status polling, triggered periodically, and executed only when the Bluetooth link is idle; The power detection module is configured as follows: Dynamically adjust the ADC sampling frequency and Bluetooth operating mode based on the current battery voltage range: First interval: When the battery voltage is greater than 3.0V, shallow monitoring mode is adopted, the ADC sampling frequency is 1 time / second, and Bluetooth is in low power sleep mode. Second interval: When the battery voltage is greater than 2.8V and less than or equal to 3.0V, a medium monitoring mode is adopted, the ADC sampling frequency is 2 times / second, and Bluetooth is in low power sleep mode; Third zone: When the battery voltage is greater than 2.6V and less than or equal to 2.8V, the altitude monitoring mode is adopted, the ADC sampling frequency is 10 times / second, and the Bluetooth connection remains active. Fourth zone: When the battery voltage is less than or equal to 2.6V, an emergency monitoring mode is adopted, the ADC continuously samples, and the Bluetooth connection remains active; The second main control module is also configured as follows: Different broadcast strategies are adopted according to the priority of the warning instructions: First priority: When the speaker receives the P0 level warning command, a forced broadcast strategy is adopted to broadcast it immediately and reduce the current music volume during the broadcast of the warning voice. Second priority: When the speaker receives the P1 level warning command, it adopts an intelligent waiting strategy to detect whether the volume of the audio signal currently played by the speaker is lower than the preset volume threshold. If so, it is determined to be a music interval and the warning is played immediately; otherwise, it waits until the volume is lower than the preset volume threshold before playing the warning. Third priority: When the speaker receives a delay request sent by the user via button or App, a temporary suppression strategy is adopted to delay the warning broadcast for a preset time, and then rebroadcast it after the delay ends.

9. The low battery voice warning system according to claim 7, characterized in that, The power detection module further includes an anti-false alarm processing unit: the anti-false alarm unit is configured to perform at least one of the following operations: Time slot avoidance: Staggering the ADC sampling time with the microphone's RF transmission time slot; Median filtering: The median value of multiple consecutive ADC sample values ​​is taken as the effective voltage value; Moving average: Performs a moving average filter on multiple consecutive ADC sample values; Hysteresis Comparison: A hysteresis comparison mechanism is adopted to make the voltage threshold for triggering the microphone warning different from the voltage threshold for clearing the warning, and the voltage threshold for clearing the warning is higher than the voltage threshold for triggering the warning. De-jitter delay: After the microphone voltage is first detected to be lower than the first preset threshold, wait for the preset delay time, and then sample again to confirm after the delay ends; Transmit power compensation: Dynamically compensate the sampled voltage value based on the microphone's current RF transmit power, or adjust the warning trigger threshold accordingly.

10. The low battery voice warning system according to claim 7, characterized in that, The wireless microphone also includes a Bluetooth audio chip, which integrates the first main control module and the first Bluetooth communication module, and has a built-in analog-to-digital converter interface for collecting battery voltage; the model of the Bluetooth audio chip is AC7066D.

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