An audio wireless transmission synchronous playing system

Abstract

The application discloses an audio wireless transmission synchronous playing system and relates to the technical field of audio synchronization. The system comprises an acoustic diagnosis control subsystem and a synchronous correction subsystem. The acoustic diagnosis control subsystem is used for collecting current environmental sound signals through a microphone built in an audio, separating high-frequency components and low-frequency components from the current environmental sound signals, determining phase offset probability density of the high-frequency components and spatial energy distribution probability density of the low-frequency components, determining a conflict value of the high-frequency components and the low-frequency components according to KL divergence of the phase offset probability density and the spatial energy distribution probability density, and executing a multi-physical field collaborative diagnosis method to obtain a diagnosis result if the conflict value is greater than a first preset conflict threshold. The synchronous correction subsystem is used for adjusting audio output of the audio in response to the diagnosis result. The application realizes improvement of wireless transmission synchronization capability of the audio.

Description

Technical Field

[0001] This invention relates to the technical field of audio synchronization, and more particularly to a wireless audio transmission and synchronized playback system. Background Technology

[0002] In multi-device synchronous playback scenarios of wireless speaker systems, audio-visual asynchrony and sound quality distortion (such as sound delay or interruption) are core issues that have long plagued user experience. The root causes of such problems are usually complex and diverse and difficult to distinguish precisely, but can be mainly summarized into two categories: environmental dynamic interference factors (such as changes in the sound wave reflection path caused by the movement of people or changes in the position of furniture) and internal hardware failure factors of the devices (such as timing disorders caused by clock circuit temperature drift or crystal oscillator frequency deviation).

[0003] Traditional solutions to overcome transmission delay and jitter often employ the strategy of expanding the audio data buffer. However, this strategy is merely a passive masking mechanism. Not only does it fail to eradicate the problem, it also introduces significant fixed delays, exacerbating the overall sluggishness of the system's response. This creates an irreconcilable contradiction in the audio-visual desynchronization problem: increasing the buffer sacrifices real-time performance (increased delay), while reducing the buffer faces a higher risk of distortion (loss of synchronization).

[0004] Therefore, improving the wireless transmission synchronization capability of audio equipment has become a pressing technical challenge. Summary of the Invention

[0005] The technical problem solved by this invention is that the synchronization capability of wireless transmission of audio equipment needs to be improved.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a wireless audio transmission and synchronous playback system, comprising an acoustic diagnostic control subsystem and a synchronization correction subsystem; the acoustic diagnostic control subsystem is used for:

[0007] The speaker uses its built-in microphone to capture ambient sound signals.

[0008] Separate the high-frequency and low-frequency components from the current ambient sound signal;

[0009] Determine the phase shift probability density of the high-frequency component and the spatial energy distribution probability density of the low-frequency component;

[0010] The conflict value between the high-frequency component and the low-frequency component is determined based on the KL divergence of the phase offset probability density and the spatial energy distribution probability density.

[0011] If the conflict value is greater than the first preset conflict threshold, then the multi-physics collaborative diagnosis method is executed to obtain the diagnosis result;

[0012] The synchronization correction subsystem is used to adjust the audio output of the speaker in response to the diagnostic results.

[0013] Preferably, the multi-physics collaborative diagnostic method executed by the acoustic diagnostic control subsystem includes:

[0014] The rate of change of the high-frequency component and the rate of change of the low-frequency component are determined based on the phase offset probability density and the spatial energy distribution probability density, respectively.

[0015] If the rate of change of the low-frequency component is greater than the rate of change of the high-frequency component, and the conflict value is greater than or equal to the first preset conflict threshold, and the conflict value is less than the second preset conflict threshold, then the diagnostic result is marked as environmental interference.

[0016] If the rate of change of the low-frequency component is less than the rate of change of the high-frequency component, or if the conflict value is greater than the second preset conflict threshold, then the electromagnetic feature analysis method is executed.

[0017] Wherein, the first preset conflict threshold is less than the second preset conflict threshold.

[0018] Preferably, the electromagnetic feature analysis method executed by the acoustic diagnostic control subsystem includes:

[0019] Listen to the electromagnetic radiation signal of the radio frequency baseband clock of the speaker;

[0020] The amplification of the odd harmonic intensity of the radio frequency baseband clock and the spectrum of the electromagnetic radiation signal are determined based on the electromagnetic radiation signal.

[0021] If an abnormal increase in the intensity of the odd harmonics is detected, the diagnostic result is marked as a clock circuit malfunction, and a temperature detection method is performed on the clock circuit of the audio device.

[0022] If abnormal broadening of the spectrum is detected, the diagnostic result is marked as power amplifier distortion, and a temperature detection method is performed on the power amplifier circuit of the speaker.

[0023] Preferably, the clock circuit and power amplifier circuit of the audio system are provided with a sealed micro-cavity, and the sealed micro-cavity contains a piezoelectric ceramic sheet; the temperature detection method executed by the acoustic diagnostic control subsystem includes:

[0024] The piezoelectric ceramic sheet emits and receives ultrasonic pulses of a fixed frequency.

[0025] Determine the flight time of the ultrasonic pulse from transmission to reception;

[0026] The internal temperature of the sealed micro-acoustic cavity is determined based on the flight time and the cavity size of the sealed micro-acoustic cavity.

[0027] If the internal temperature of the sealed micro-acoustic cavity of the clock circuit is greater than the preset temperature threshold, the diagnostic result will be marked as a thermally induced fault.

[0028] If the rate of temperature rise inside the sealed micro-cavity of the power amplifier circuit is greater than the preset rate of temperature rise, the diagnostic result will be marked as a thermally induced fault.

[0029] Preferably, the multi-physics collaborative diagnostic method executed by the acoustic diagnostic control subsystem further includes:

[0030] Vibration signals in a preset frequency band are collected by a piezoelectric ceramic sheet attached to the circuit board connector of the speaker.

[0031] If the acoustic diagnostic control subsystem marks the diagnostic result as a thermally induced fault, then it determines whether the vibration signal is abnormal.

[0032] If the vibration signal is abnormal, the diagnostic result will be marked as a loose connector.

[0033] Preferably, the synchronization correction subsystem is used for:

[0034] If the diagnostic result is marked as environmental interference, then the low-frequency component is compensated;

[0035] If the diagnostic result is marked as a clock circuit abnormality, the clock compensation amount is determined according to the phase offset probability density, and the clock source timing of the RF baseband clock is adjusted according to the clock compensation amount.

[0036] If the diagnostic result is marked as power amplifier distortion, the spectral envelope of the electromagnetic radiation signal is extracted, a pre-distortion signal with the opposite distortion characteristics is generated based on the spectral envelope, and the pre-distortion signal is injected into the input stage of the power amplifier of the audio system.

[0037] If the diagnostic result is marked as a thermally induced fault, the bias voltage of the power amplifier is reduced to a preset voltage level.

[0038] Preferably, separating the high-frequency component and the low-frequency component from the current ambient sound signal includes:

[0039] High-frequency and low-frequency components are separated from the current ambient sound signal using a preset high-pass filter and a preset low-pass filter.

[0040] Determining the phase shift probability density of the high-frequency component and the spatial energy distribution probability density of the low-frequency component includes:

[0041] Extract the zero-crossing time sequence of the high-frequency components;

[0042] The phase shift distribution histogram of the zero-crossing time series is generated by a preset kernel density estimation algorithm to obtain the phase shift probability density;

[0043] Determine the spatial energy distribution probability density of the low-frequency component.

[0044] Preferably, determining the spatial energy distribution probability density of the low-frequency component includes:

[0045] Obtain the kurtosis value from the phase offset distribution histogram;

[0046] Obtain a spatial grid distribution map of the sound field space where the speaker is located;

[0047] The sound pressure value of each grid in the spatial grid distribution map is determined by a preset beamforming algorithm;

[0048] The energy distribution variance is determined based on the sound pressure value of each grid in the spatial grid distribution map, and the spatial energy distribution probability density is obtained.

[0049] The step of determining the conflict value between the high-frequency component and the low-frequency component based on the KL divergence of the phase shift probability density and the spatial energy distribution probability density includes:

[0050] Determine the KL divergence of the phase shift probability density and the spatial energy distribution probability density;

[0051] The conflict value between the high-frequency component and the low-frequency component is determined based on the kurtosis value in the phase offset distribution histogram and the KL divergence.

[0052] Preferably, the synchronization correction subsystem is used for:

[0053] If the diagnostic result is marked as environmental interference, the low-frequency component is divided into a first low-frequency sub-component and a second low-frequency sub-component. The first low-frequency sub-component is located in a first band range, and the second low-frequency sub-component is located in a second band range. The first band range is higher than the second band range.

[0054] The audio amplitude of the speaker's output audio is identified by the speaker's locator;

[0055] If the audio amplitude is within the first volume range, then the first low-frequency sub-component is enhanced;

[0056] If the audio amplitude is within the second volume range, then the first low-frequency sub-component is attenuated and the second low-frequency sub-component is amplified, wherein the first volume range is lower than the second volume range.

[0057] Preferably, if the diagnostic result is marked as a clock circuit abnormality, determining the clock compensation amount based on the phase offset probability density and adjusting the clock source timing of the RF baseband clock based on the clock compensation amount includes:

[0058] If the diagnostic result is marked as a clock circuit malfunction, then a preset acoustic wave phase reference value is obtained;

[0059] Determine the phase deviation between the phase offset probability density and the preset acoustic phase reference value;

[0060] The clock compensation amount is determined based on the phase deviation.

[0061] Adjust the clock source timing of the RF baseband clock according to the clock compensation amount.

[0062] The beneficial effects of this invention are as follows: By determining the phase shift probability density of the high-frequency component and the spatial energy distribution probability density of the low-frequency component, the phase shift probability density characterizes the high-frequency sound wave phase shift directly caused by the clock deviation of the audio equipment, and the spatial energy distribution probability density characterizes the distortion of the low-frequency propagation path caused by abrupt changes in the sound field environment. The conflict value between the high-frequency and low-frequency components is determined based on the KL divergence of the phase shift probability density and the spatial energy distribution probability density. This conflict value reflects the degree of deviation between the changing trends of the phase shift probability density and the spatial energy distribution probability density. A high degree of deviation indicates equipment failure or abrupt changes in the sound field environment. Furthermore, if the deviation is dominated by low frequencies, it indicates abrupt changes in the sound field environment; if the deviation is dominated by high frequencies, it indicates equipment failure. This allows for adjustments to the audio system based on the cause of the conflict, thereby improving the wireless transmission synchronization capability of the audio system. Attached Figure Description

[0063] Figure 1 This is a basic flowchart of a wireless audio transmission and synchronous playback system provided in one embodiment of the present invention. Detailed Implementation

[0064] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0065] When users experience sound delays or distortion, audio systems struggle to determine whether the issue stems from changes in the physical environment (such as furniture movement affecting the sound field) or from device malfunctions (such as clock chip drift). Current technologies lack effective means to accurately identify the source of the fault at the device level. Whether relying on network-level timestamp calibration, master-slave device signal strength monitoring, or simple environmental acoustic averaging analysis, it's difficult to reliably distinguish whether a sudden change in the environmental sound field triggers sound wave propagation distortion, or whether a hardware malfunction in the device's timing mechanism causes a disruption in signal generation and playback. This lack of diagnostic capability prevents the system from implementing targeted and efficient corrective measures, forcing it to rely on general, often costly, compensation mechanisms (such as expanding the audio data buffer), which not only fail to address the problem but also introduce additional latency.

[0066] The inventors of this application discovered in their actual research that the high-frequency phase change (time dimension) and low-frequency sound field distribution (spatial dimension) of an acoustic system are essentially two naturally existing independent sensors. Their different response modes to environmental interference and equipment failure reveal a weak correlation between the high-frequency phase shift probability distribution P_t and the low-frequency sound field density P_s under normal conditions. When the audio equipment malfunctions, P_t changes drastically while P_s remains stable (an anomaly in the time dimension); under environmental interference, P_s changes drastically while P_t remains relatively stable (an anomaly in the spatial dimension). Analysis of the sound wave data collected by the audio system itself reveals that high-frequency sound waves (>5kHz) and low-frequency sound waves (<200Hz) exhibit quantifiable inverse changes under fault conditions, essentially stemming from the physical sensitivity differences of sound waves in the time and spatial dimensions. Specifically, the time-domain sensitivity of high-frequency sound waves means that device clock deviations will directly cause phase shifts in high-frequency sound waves, which manifests as sharp peaks in the probability density distribution of waveform periodic changes (denoted as PDF_t); the spatial sensitivity of low-frequency sound waves means that abrupt changes in the sound field environment (such as furniture displacement) will distort the low-frequency propagation path, which manifests as diffusion of the probability density of sound energy spatial distribution (denoted as PDF_s).

[0067] When the trends of the two types of data show a strong divergence (e.g., PDF_t fluctuates wildly while PDF_s remains stable), the source of the fault can be identified. By simultaneously monitoring the characteristics of these two types of data, the source of the anomaly can be located.

[0068] Specifically, please refer to Figure 1 This illustration shows an embodiment of the present invention, which provides a wireless audio transmission and synchronous playback system, the system including an acoustic diagnostic control subsystem and a synchronization correction subsystem.

[0069] Specifically, the speaker includes a microphone, a wireless audio receiver, a digital signal processor (DSP), a power amplifier, and a speaker. The DSP incorporates algorithms to perform multi-physics collaborative diagnostic methods, or these methods are performed via an ARM chip. Preferably, the clock circuit and power amplifier circuit of the speaker have sealed microcavities on their surfaces. Each sealed microcavity contains a piezoelectric ceramic sheet. Sealed microcavities (<1cm³ in size) are attached to or near the surfaces of the clock circuit and power amplifier circuit to transfer heat into them. The temperature inside the sealed microcavities reflects the temperature of the clock circuit or power amplifier circuit.

[0070] The acoustic diagnostic control subsystem is used to: acquire the current ambient sound signal through the microphone built into the speaker; separate the high-frequency component and the low-frequency component from the current ambient sound signal; determine the phase shift probability density of the high-frequency component and the spatial energy distribution probability density of the low-frequency component; determine the conflict value of the high-frequency component and the low-frequency component based on the KL divergence of the phase shift probability density and the spatial energy distribution probability density; and if the conflict value is greater than a first preset conflict threshold, execute the multi-physics field collaborative diagnostic method to obtain the diagnostic result.

[0071] Preferably, separating high-frequency and low-frequency components from the current ambient sound signal includes: separating high-frequency and low-frequency components from the current ambient sound signal using a preset high-pass filter and a preset low-pass filter; determining the phase shift probability density of the high-frequency component and the spatial energy distribution probability density of the low-frequency component, including: extracting the zero-crossing time sequence of the high-frequency component; generating a phase shift distribution histogram of the zero-crossing time sequence using a preset kernel density estimation algorithm to obtain the phase shift probability density; obtaining the kurtosis value in the phase shift distribution histogram; obtaining a spatial grid distribution map of the sound field space where the speaker is located; determining the sound pressure value of each grid in the spatial grid distribution map using a preset beamforming algorithm; determining the energy distribution variance based on the sound pressure value of each grid in the spatial grid distribution map to obtain the spatial energy distribution probability density; and determining the conflict value between the high-frequency and low-frequency components based on the KL divergence of the phase shift probability density and the spatial energy distribution probability density, including: determining the KL divergence of the phase shift probability density and the spatial energy distribution probability density; and determining the conflict value between the high-frequency and low-frequency components based on the kurtosis value and the KL divergence in the phase shift distribution histogram.

[0072] The synchronization system's algorithm configuration is as follows: the current ambient sound signal is separated into high-frequency components (>5kHz) and low-frequency components (<200Hz); the temporal characteristic change rate of the high-frequency components (e.g., phase offset PDF_t) is calculated; the spatial characteristic distribution of the low-frequency components (e.g., acoustic energy space PDF_s) is calculated; a conflict value δ (0≤δ≤1) is generated based on the dynamic difference between the temporal characteristic change rate and the spatial characteristic distribution; when the conflict value δ exceeds a preset warning threshold (e.g., δ>0.2), a primary acoustic anomaly event is identified, triggering the synchronization system to troubleshoot the fault.

[0073] Specifically, the original sound signal is acquired using the built-in microphone of the speaker at a sampling rate of 1ms; a 5kHz high-pass filter and a 200Hz low-pass filter are used to separate the high-frequency and low-frequency components; the phase shift probability density PDF_t of the high-frequency component is calculated every 10ms, and the zero-crossing time sequence {t1, t2,...,t} of the high-frequency signal within the current 10ms is extracted. n A phase shift distribution histogram is generated based on kernel density estimation, and its kurtosis value is denoted as K_t. The spatial energy distribution PDF_s of the low-frequency component is calculated every 50ms. A 0.5m × 0.5m grid is established in the sound field space (the sound field space is determined by scanning the user's residence through a configured mobile APP and saved to the cloud; when the speaker is connected to the mobile phone, the APP transmits the data corresponding to the sound field space to the speaker device). The sound pressure value of each grid is calculated using a beamforming algorithm to generate the energy distribution variance σ_s². According to the formula δ = D kl (PDF_t ||PDF_s) + |K_t - 2| / 10 calculates the conflict value (D kl (where δ is the KL divergence); if δ > 0.2, activate the multiphysics collaborative diagnostic method.

[0074] D kl The physical meaning of (PDF_t || PDF_s) is to measure the "abnormal contradiction value" between high-frequency sound waves (time domain behavior) and low-frequency sound waves (spatial domain behavior). Its working principle is that when environmental interference is dominant (such as movement), the changing trends of high and low frequency sound waves are basically synchronized (small deviation, low value). When equipment failure is dominant (such as clock drift), high-frequency sound waves fluctuate violently while low-frequency sound waves remain relatively stable (large deviation, high value). The physical meaning of |K_t - 2| / 10 is to detect whether high-frequency sound waves exhibit sudden anomalies. Its working principle is that K_t describes the sharpness of sudden changes in the high-frequency sound wave waveform (called "kurtosis"). Ideally, the sound wave kurtosis ≈ 3 (smooth fluctuation). When the clock circuit fails, the electrical signal suddenly drifts, causing spikes in the sound wave waveform, leading to a significant decrease in K_t (close to 2). Dividing by 10 is a normalization operation, making the value range between 0 and 1.

[0075] Certain environmental disturbances (such as suddenly closing a window) can cause D kl A brief spike occurs (misjudged as an audio equipment malfunction), but at this time, the high-frequency sound wave will not exhibit a sustained waveform spike (K_t remains approximately 3, causing the second part to suppress the δ value). A clock circuit malfunction can cause a divergence between high and low frequency behavior (D). kl Increasing the value of D will inevitably lead to high-frequency waveform distortion (|K_t - 2| increases), therefore, D kl The superposition of the two parts (PDF_t|| PDF_s) and |K_t - 2| / 10 significantly improves the detection confidence.

[0076] δ is a value between 0 and 1. The larger δ is, the more intense the contradiction between "time" and "space", and the more likely it is a device clock problem (rather than environmental interference). If δ < 0.3, it means that environmental interference is more important (large spatial fingerprint changes, relatively stable temporal fingerprint); if δ ≥ 0.3, it means that the device's own clock failure is more important (large temporal fingerprint changes, relatively stable spatial fingerprint).

[0077] Therefore, in one alternative approach, diagnosis can be directly based on the magnitude of the conflict value δ. For example, if 0.2 < δ < 0.3, it is determined to be environmental interference (dominated by PDF_s changes), and if δ ≥ 0.3, it is determined to be equipment failure (dominated by PDF_t changes). Furthermore, the diagnostic results are pushed to a mobile app.

[0078] Low-frequency sounds (<200Hz) have long wavelengths and strong diffraction capabilities (like ripples on water), easily bypassing obstacles and dispersing within a room based on sound wave diffraction laws. They are exceptionally sensitive to changes in room shape (spatial area). High-frequency sounds (>5kHz) have short wavelengths and strong directionality. As indicated by sound wave reflection laws, they are easily blocked or reflected by obstacles and are exceptionally sensitive to minute time differences in their propagation path. If the internal clock of an audio system is slightly off, these "short and sharp" high-frequency sound waves immediately undergo strong time waveform distortion / phase shift. Therefore, the characteristic changes of these two types of sound waves can be analyzed separately (low frequencies are analyzed by whether the spatial energy distribution is "diffuse," and high frequencies by whether the time waveform is "abrupt"). By quantifying the degree of difference in their changes (δ value), environmental interference (dominated by low-frequency changes) and equipment malfunctions (dominated by high-frequency changes) can be distinguished.

[0079] Furthermore, a multi-physics collaborative diagnostic method is used for specific diagnosis. The multi-physics collaborative diagnostic method executed by the acoustic diagnostic control subsystem includes: determining the rate of change of the high-frequency component and the rate of change of the low-frequency component based on the phase shift probability density and the spatial energy distribution probability density, respectively; if the rate of change of the low-frequency component is greater than the rate of change of the high-frequency component, and the conflict value is greater than or equal to a first preset conflict threshold and less than a second preset conflict threshold, then the diagnostic result is marked as environmental interference; if the rate of change of the low-frequency component is less than the rate of change of the high-frequency component, or the conflict value is greater than the second preset conflict threshold, then an electromagnetic feature analysis method is executed; wherein, the first preset conflict threshold is less than the second preset conflict threshold.

[0080] The electromagnetic characteristic analysis methods performed by the acoustic diagnostic control subsystem include: monitoring the electromagnetic radiation signal of the radio frequency baseband clock of the audio system; determining the increase in the odd harmonic intensity of the radio frequency baseband clock and the spectrum of the electromagnetic radiation signal based on the electromagnetic radiation signal; if an abnormal increase in the odd harmonic intensity is detected, the diagnostic result is marked as a clock circuit malfunction, and a temperature detection method is performed on the audio system's clock circuit; if an abnormal broadening of the spectrum is detected, the diagnostic result is marked as power amplifier distortion, and a temperature detection method is performed on the audio system's power amplifier circuit.

[0081] The temperature detection method executed by the acoustic diagnostic control subsystem includes: emitting and receiving ultrasonic pulses of a fixed frequency via a piezoelectric ceramic sheet; determining the flight time of the ultrasonic pulse from emission to reception; determining the internal temperature of the sealed micro-acoustic cavity based on the flight time and the cavity size of the sealed micro-acoustic cavity; if the internal temperature of the sealed micro-acoustic cavity of the clock circuit is greater than a preset temperature threshold, the diagnostic result is marked as a thermally induced fault; if the rate of temperature rise of the sealed micro-acoustic cavity of the power amplifier circuit is greater than a preset temperature rise rate, the diagnostic result is marked as a thermally induced fault.

[0082] The acoustic diagnostic control subsystem is also used to perform the following: collecting vibration signals in a preset frequency band through a piezoelectric ceramic plate attached to the connector of the speaker's circuit board; if the acoustic diagnostic control subsystem marks the diagnostic result as a thermally induced fault, it determines whether the vibration signal is abnormal; if the vibration signal is abnormal, it marks the diagnostic result as a loose connector.

[0083] The acoustic diagnostic control subsystem executes a multi-physics collaborative diagnostic method to automatically and accurately identify the root cause of sound asynchrony or distortion when there are abnormalities inside the audio equipment.

[0084] In electromagnetic fields, specifically, relying solely on sound signals is sometimes insufficient to pinpoint the exact circuit board or chip causing the problem—for example, whether it's a clock issue or a power supply issue. Electronic devices (such as clock chips and amplifier chips) actively radiate specific weak electromagnetic waves (a specific fundamental frequency plus harmonics) during operation. When internal circuitry malfunctions, for example, if the clock circuit is inaccurate or interfered with (such as by power supply ripple), the intensity of specific odd-order harmonics (such as the 3rd and 5th harmonics) in the radiated electromagnetic waves will abnormally increase. When an amplifier chip is unstable or distorted, its radiated electromagnetic wave spectrum will become "wider" and "more distorted." Therefore, the health status of internal circuitry can be inferred based on these electromagnetic waves emitted by the Wi-Fi or Bluetooth antennas already present inside the speaker.

[0085] In a temperature stress field, specifically, many internal faults (such as power amplifier overheating or loose connectors) are strongly correlated with temperature and material thermal deformation. Existing sensors (such as thermistors) are inexpensive but generally ineffective. However, in air (or other gases), the higher the temperature, the faster the sound travels (more vigorous molecular motion). Electronic devices are composed of different materials (metals, plastics, ceramics, silicon wafers), which expand to different degrees when heated (differences in their coefficients of thermal expansion). When the temperature changes rapidly, tiny pressure, friction, and even extremely faint "squeaking" sounds (structural noise) can occur at the contact points between these different materials.

[0086] Therefore, a very small, sealed air cavity (costing almost nothing, just a specially shaped gap) can be encapsulated in key heat-generating areas inside the speaker (such as near the clock chip or amplifier chip). Inside this small cavity, a miniature, inexpensive piezoelectric ceramic plate is installed. A synchronization system periodically (e.g., once per second) emits a fixed, very short sound wave signal (such as a 40kHz ultrasonic wave) into this cavity. The synchronization system precisely measures the time it takes for this sound wave to travel from one end of the cavity to the other (Time of Flight, ToF). Because the physical dimensions of the cavity are fixed and known—the cavity length and the frequency of the emitted sound wave are known—the actual time of sound wave travel depends primarily on the temperature of the air inside the cavity, as temperature changes the speed of sound.

[0087] According to the physical law formula: Speed ​​= Distance / Time, by measuring the flight time and knowing the fixed distance (cavity length), the actual speed of sound propagation within the cavity can be calculated. Then, based on the known relationship between the speed of sound and temperature, the average temperature within this small cavity can be accurately deduced. This method is cheaper, more interference-resistant (electromagnetism does not affect sound waves), and has a faster response time than ordinary temperature sensors, perfectly sensing the temperature of key heat-generating areas inside the speaker.

[0088] Based on this, the fault diagnosis process is as follows:

[0089] Analyze the dominance of low-frequency PDF_s and high-frequency PDF_t changes. If the low-frequency change is significantly dominant (e.g., ΔPDF_s>>ΔPDF_t), and the δ value is at the warning threshold but below the equipment fault threshold (0.2 ≤ δ<0.3), then the environmental interference response module (fast path) is directly activated. The electromagnetic / thermal characteristics of this path are not activated.

[0090] If high-frequency changes significantly dominate (e.g., ΔPDF_t >> ΔPDF_s) or the changes are comparable but δ ≥ 0.3, a "suspected equipment failure subprocess" is triggered, followed by electromagnetic verification: If odd harmonics are significantly enhanced, strong evidence supports clock / timing-related faults, triggering temperature checks to locate / rule overheating causes; if the spectrum is broadened / rough, but without specific odd harmonic spikes, it may point to the power amplifier or other non-clock distortion sources, initiating temperature and stress depth checks to locate power amplifier / thermal-related faults; if there are no significant electromagnetic anomalies, warning information is generated, high δ values ​​without electromagnetic anomalies should raise suspicion of intermittent strong interference or sensor faults.

[0091] During temperature checks, cavity ToF temperature measurement is used. If the clock area temperature is below the safety limit and the temperature change rate is stable, it confirms that the clock anomaly is not directly caused by temperature. The problem is more likely to originate from power supply noise, crystal oscillator aging, or electromagnetic crosstalk. This is classified as a "pure clock circuit fault" (not caused by heat) with high confidence, triggering clock calibration and repair. If the temperature is above the safety limit or the temperature change rate is abnormally high, it is considered that the clock anomaly is likely caused or aggravated by overheating. The problem may originate from poor heat dissipation, partial short circuit, or other heat-generating components. This is classified as a "thermal-induced clock fault" with high confidence, triggering clock calibration and thermal management responses (cooling / power reduction / user alarms), and entering stress checks. Overheating may be accompanied by thermal stress. Based on the gas sound velocity formula v = 331.3 × sqrt(1 + T / 273) and the cavity length L, the temperature T = (v × v) / (331.3²) - 273 can be deduced. If T > T_max (T_max = 85℃) or dT / dt > 5℃ / s, it is marked as a thermally induced fault.

[0092] During stress checks, if the temperature gradient in the high-temperature area is steep and accompanied by significant thermal stress sounds, a strong warning can be issued. This area has a serious risk of material fatigue / connection failure due to thermal stress (such as solder joint cracking or accelerated connector oxidation). This triggers a deep thermal management + user preventive maintenance alarm and indicates potential future functional deterioration. If the temperature is high but the thermal stress sounds are weak, it is more likely to be an instantaneous overload / temporary obstruction of heat dissipation rather than long-term stress damage. In this case, power amplifier compensation (such as linearization) and active cooling are triggered first.

[0093] Specifically, electromagnetic feature analysis reuses the wireless communication antenna (such as Wi-Fi / Bluetooth antenna) of the audio equipment to monitor the equipment's own electromagnetic radiation signal during the activation of the audio equipment fault triggering conditions; detects the intensity changes of odd harmonics of the clock fundamental frequency (such as the 3rd / 5th harmonics); quantifies the degree of spectral broadening (such as bandwidth variance); when an abnormal increase in the intensity of odd harmonics is detected, the temperature of the clock region is required to be located; when spectral broadening is detected and there are no abnormal odd harmonics, the temperature and stress signal of the power amplifier region are triggered to be located.

[0094] A sealed gas cavity (size <1cm³) is set up near the clock chip / power amplifier chip; a fixed frequency sound wave (e.g., 40kHz) is emitted and received through a piezoelectric ceramic sheet built into the cavity; the gas temperature inside the cavity is inferred based on the time to fire (ToF) of the sound wave and the known cavity size; the structural acoustic signal (frequency range 1k-5kHz) of the cavity area is collected synchronously; if the temperature is greater than the safety threshold when the clock is abnormal, it is marked as "thermal induced failure"; if the structural acoustic intensity is greater than the risk threshold when the power amplifier is abnormal, it is marked as "connection stress risk".

[0095] For pure clock faults, a clock fine-tuning signal is generated based on the high-frequency phase offset (step accuracy ±0.1ms); for thermally induced clock faults, fan control commands and user heat dissipation alarms are sent synchronously; for power amplifier distortion faults, a pre-distortion compensation signal is injected; and for connection stress risks, equipment maintenance early warning commands are generated.

[0096] The synchronous correction subsystem is used to adjust the audio output of the speaker in response to the diagnostic results.

[0097] Specifically, if the diagnostic result is marked as environmental interference, the low-frequency component is compensated; if the diagnostic result is marked as clock circuit abnormality, the clock compensation amount is determined according to the phase offset probability density, and the clock source timing of the RF baseband clock is adjusted according to the clock compensation amount; if the diagnostic result is marked as power amplifier distortion, the spectral envelope of the electromagnetic radiation signal is extracted, a pre-distortion signal with the opposite distortion characteristics is generated according to the spectral envelope, and the pre-distortion signal is injected into the input stage of the audio power amplifier; if the diagnostic result is marked as thermally induced fault, the bias voltage of the power amplifier is reduced to a preset voltage level.

[0098] If the diagnostic result is marked as environmental interference, the low-frequency component is divided into a first low-frequency sub-component and a second low-frequency sub-component. The first low-frequency sub-component is located in the first band range, and the second low-frequency sub-component is located in the second band range. The first band range is higher than the first band range. The audio amplitude of the speaker's output audio is identified by the speaker's locator. If the audio amplitude is within the first volume range, the first low-frequency sub-component is enhanced. If the audio amplitude is within the second volume range, the first low-frequency sub-component is attenuated, and the second low-frequency sub-component is enhanced. The first volume range is lower than the second audio range.

[0099] If the diagnostic result indicates a clock circuit malfunction, the clock compensation amount is determined based on the phase offset probability density, and the clock source timing of the RF baseband clock is adjusted based on the clock compensation amount. This includes: if the diagnostic result indicates a clock circuit malfunction, obtaining a preset acoustic phase reference value; determining the phase deviation between the phase offset probability density and the preset acoustic phase reference value; determining the clock compensation amount based on the phase deviation; and adjusting the clock source timing of the RF baseband clock based on the clock compensation amount.

[0100] If the fault is identified as a clock circuit fault, calculate the clock compensation Δτ = α ∫(K_t - 2)dt + β d(K_t) / dt (α=0.05, β=0.1), adjust the DSP clock source divider register via the I²C bus, and calibrate the step by ±0.1ms. If the fault is identified as power amplifier distortion, extract the electromagnetic signal spectrum envelope E(f), generate the predistortion filter coefficients H_comp(f) = 1 / E(f), and inject the inverse response signal of H_comp(f) into the DSP preamplifier. If the fault is identified as a thermally induced fault, reduce the power amplifier bias voltage by 20%. If there is a stress problem, broadcast maintenance instructions via Bluetooth.

[0101] Optionally, the compensation amount Δτ of the clock calibration module satisfies: Δτ = α·(∫(PDF_t - PDF_t0)dt) +β·d(PDF_t) / dt, where α and β are proportional-integral coefficients, and PDF_t0 is the reference phase distribution.

[0102] Preferably, bass is enhanced at low volumes and weakened at high volumes. Below 1 / 3 of the maximum volume, the proportion of the 50Hz low-frequency band is increased; between 1 / 3 and 2 / 3 of the volume, the 50Hz low-frequency band remains unchanged; above 2 / 3 of the maximum volume, the 50Hz band is attenuated, while the 100Hz band is boosted. This linear adjustment supplements the low-frequency components.

[0103] This application embodiment determines the phase shift probability density of the high-frequency component and the spatial energy distribution probability density of the low-frequency component. The phase shift probability density characterizes the phase shift of the high-frequency sound wave directly caused by the clock deviation of the audio equipment, and the spatial energy distribution probability density characterizes the distortion of the low-frequency propagation path caused by abrupt changes in the sound field environment. The conflict value between the high-frequency and low-frequency components is determined based on the KL divergence of the phase shift probability density and the spatial energy distribution probability density. The conflict value reflects the degree of deviation of the changing trends of the phase shift probability density and the spatial energy distribution probability density. If the degree of deviation is high, it indicates equipment failure or abrupt changes in the sound field environment. Furthermore, if the degree of deviation is dominated by low frequencies, it indicates abrupt changes in the sound field environment; if the degree of deviation is dominated by high frequencies, it indicates equipment failure. This allows for adjustments to the audio system based on the cause of the conflict, thereby improving the wireless transmission synchronization capability of the audio system.

[0104] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media containing computer-usable program code. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), Programmable Red-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0105] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A wireless audio transmission and synchronous playback system, characterized in that, It includes an acoustic diagnostic control subsystem and a synchronization correction subsystem; the acoustic diagnostic control subsystem is used for: The speaker uses its built-in microphone to capture ambient sound signals. High-frequency and low-frequency components are separated from the current ambient sound signal using a preset high-pass filter and a preset low-pass filter. Extract the zero-crossing time sequence of the high-frequency components; The phase shift distribution histogram of the zero-crossing time series is generated by a preset kernel density estimation algorithm to obtain the phase shift probability density; Determining the spatial energy distribution probability density of the low-frequency component specifically includes: Obtain the kurtosis value from the phase offset distribution histogram; Obtain a spatial grid distribution map of the sound field space where the speaker is located; The sound pressure value of each grid in the spatial grid distribution map is determined by a preset beamforming algorithm; The energy distribution variance is determined based on the sound pressure value of each grid in the spatial grid distribution map, and the spatial energy distribution probability density is obtained. Determine the KL divergence of the phase shift probability density and the spatial energy distribution probability density; The conflict value between the high-frequency component and the low-frequency component is determined based on the kurtosis value in the phase offset distribution histogram and the KL divergence. If the conflict value is greater than the first preset conflict threshold, then the multi-physics collaborative diagnosis method is executed to obtain the diagnosis result; The multi-physics collaborative diagnostic method executed by the acoustic diagnostic control subsystem includes: The rate of change of the high-frequency component and the rate of change of the low-frequency component are determined based on the phase offset probability density and the spatial energy distribution probability density, respectively. If the rate of change of the low-frequency component is greater than the rate of change of the high-frequency component, and the conflict value is greater than or equal to the first preset conflict threshold, and the conflict value is less than the second preset conflict threshold, then the diagnostic result is marked as environmental interference. If the rate of change of the low-frequency component is less than the rate of change of the high-frequency component, or if the conflict value is greater than the second preset conflict threshold, then the electromagnetic feature analysis method is executed. Wherein, the first preset conflict threshold is less than the second preset conflict threshold; The electromagnetic feature analysis method executed by the acoustic diagnostic control subsystem includes: Listen to the electromagnetic radiation signal of the radio frequency baseband clock of the speaker; The amplification of the odd harmonic intensity of the radio frequency baseband clock and the spectrum of the electromagnetic radiation signal are determined based on the electromagnetic radiation signal. If an abnormal increase in the intensity of the odd harmonics is detected, the diagnostic result is marked as a clock circuit malfunction, and a temperature detection method is performed on the clock circuit of the audio device. If abnormal broadening of the spectrum is detected, the diagnostic result is marked as power amplifier distortion, and a temperature detection method is performed on the power amplifier circuit of the speaker. The clock circuit and power amplifier circuit of the audio system are provided with sealed microcavities, and piezoelectric ceramic plates are built into the sealed microcavities; the temperature detection method executed by the acoustic diagnostic control subsystem includes: The piezoelectric ceramic sheet emits and receives ultrasonic pulses of a fixed frequency. Determine the flight time of the ultrasonic pulse from transmission to reception; The internal temperature of the sealed micro-acoustic cavity is determined based on the flight time and the cavity size of the sealed micro-acoustic cavity. If the internal temperature of the sealed micro-acoustic cavity of the clock circuit is greater than the preset temperature threshold, the diagnostic result will be marked as a thermally induced fault. If the rate of temperature rise inside the sealed micro-acoustic cavity of the power amplifier circuit is greater than the preset rate of temperature rise, the diagnostic result will be marked as a thermally induced fault. The multi-physics collaborative diagnostic method executed by the acoustic diagnostic control subsystem further includes: Vibration signals in a preset frequency band are collected by a piezoelectric ceramic sheet attached to the circuit board connector of the speaker. If the acoustic diagnostic control subsystem marks the diagnostic result as a thermally induced fault, then it determines whether the vibration signal is abnormal. If the vibration signal is abnormal, the diagnostic result will be marked as a loose connector; The synchronization correction subsystem is used to adjust the audio output of the speaker in response to the diagnostic results.

2. The system as described in claim 1, characterized in that, The synchronization correction subsystem is used for: If the diagnostic result is marked as environmental interference, then the low-frequency component is compensated; If the diagnostic result is marked as a clock circuit abnormality, the clock compensation amount is determined according to the phase offset probability density, and the clock source timing of the RF baseband clock is adjusted according to the clock compensation amount. If the diagnostic result is marked as power amplifier distortion, the spectral envelope of the electromagnetic radiation signal is extracted, a pre-distortion signal with the opposite distortion characteristics is generated based on the spectral envelope, and the pre-distortion signal is injected into the input stage of the power amplifier of the audio system. If the diagnostic result is marked as a thermally induced fault, the bias voltage of the power amplifier is reduced to a preset voltage level.

3. The system as described in claim 1, characterized in that, The synchronization correction subsystem is used for: If the diagnostic result is marked as environmental interference, the low-frequency component is divided into a first low-frequency sub-component and a second low-frequency sub-component. The first low-frequency sub-component is located in a first band range, and the second low-frequency sub-component is located in a second band range. The first band range is higher than the second band range. The audio amplitude of the speaker's output audio is identified by the speaker's locator; If the audio amplitude is within the first volume range, then the first low-frequency sub-component is enhanced; If the audio amplitude is within the second volume range, then the first low-frequency sub-component is attenuated and the second low-frequency sub-component is amplified, wherein the first volume range is lower than the second volume range.

4. The system as described in claim 2, characterized in that, If the diagnostic result is marked as a clock circuit abnormality, then the clock compensation amount is determined based on the phase offset probability density, and the clock source timing of the RF baseband clock is adjusted according to the clock compensation amount, including: If the diagnostic result is marked as a clock circuit malfunction, then a preset acoustic wave phase reference value is obtained; Determine the phase deviation between the phase offset probability density and the preset acoustic phase reference value; The clock compensation amount is determined based on the phase deviation. Adjust the clock source timing of the RF baseband clock according to the clock compensation amount.

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