A cross-channel ultrasonic alert system for active noise cancelling headphones

Abstract

This invention discloses a cross-channel ultrasonic alarm system for active noise-canceling headphones, characterized by comprising a data acquisition module, an input conversion module, a signal modulation module, and a transmission module. The data acquisition module collects control signals and transmits them to the input conversion module; the input conversion module receives the input information from the data acquisition module, converts it into alarm audio data, and transmits it to the signal modulation module; the signal modulation module modulates the alarm audio data into a specific PWM wave data stream using a PWM modulation component; and the transmission module transmits ultrasonic information based on the received PWM wave data stream. This invention achieves cross-channel information transmission at the physical layer through an ultrasonic modulation method, proposing a novel ultrasonic alarm system for active noise-canceling headphones. This reduces the risk of danger to active noise-canceling headphone users who cannot hear external sounds when noise-canceling mode is activated.

Description

Technical Field

[0001] This invention belongs to the field of cross-channel communication, specifically designing an open-loop ultrasonic alarm system for active noise-canceling headphones based on a microcontroller and frequency calculation algorithm. Background Technology

[0002] Currently, active noise cancellation technology is widely used in mid-to-high-end headphones. The mainstream noise cancellation technology is ANC (Active Noise Control). Its main principle is to collect ambient noise and generate an inverse signal with the same frequency and amplitude as the noise signal, but with a phase difference of 180 degrees. This signal is then played back and superimposed on the original signal to achieve phase cancellation and thus cancel the noise. However, most active noise-canceling headphones on the market choose to cancel all received mid-to-low frequency sounds. This indiscriminate noise cancellation will also eliminate important life alarm sounds within the noise cancellation frequency range, creating a significant safety hazard. Currently, many manufacturers have proposed corresponding solutions to this problem, such as adding automatic alarms in the headphones or alarms accessed via an app. However, these all rely on the mobile phone to automatically obtain surrounding safety information and actively issue alarms from the headphones. When the mobile app cannot obtain alarm information, the reliability of this type of alarm method is low. In response, this invention analyzes this shortcoming of active noise-canceling headphones and makes reasonable use of ultrasonic physical modules to realize a low-cost, highly scalable, and widely applicable alarm system. This alarm system can be emitted by a main body outside the headphones and mobile phone, filling a gap in the safety alarm system. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a cross-channel ultrasonic alarm system for active noise-canceling headphones, offering an alarm method that can be issued externally to users of active noise-canceling headphones.

[0004] The present invention solves its technical problem by adopting the following technical solution.

[0005] First, the principle of active noise-canceling headphones is to calculate the out-of-phase of the original noise using electronic circuitry, and output a sound wave with the same frequency and amplitude as the original noise but opposite phase, thus canceling out the original noise. To achieve this, the noise-canceling module of the active noise-canceling headphones must have a response frequency that corresponds to the frequency of the noise. When processing sound waves, regardless of the type of ANC technology used, or whether digital or analog circuitry is used, it can only process sound waves within a single frequency range. For ultrasound, the processing speed of the noise-canceling circuit cannot keep up with the frequency of the sound wave, resulting in significant noise.

[0006] A cross-channel ultrasonic alarm system for active noise-canceling headphones includes a data acquisition module, an input conversion module, a signal modulation module, and a transmission module.

[0007] The acquisition module includes an autonomous signal acquisition component, an environmental sensor, and a manual input signal component, used to collect control signals and transmit them to the input conversion module. The input conversion module includes a data selection component and a signal transmission component, used to receive the input information transmitted by the acquisition module, convert it into alarm audio data, and transmit it to the signal modulation module. The signal modulation module includes a PWM modulation component, which modulates the alarm audio data into a specific PWM wave data stream. The transmission module includes a signal generator, a power amplifier, and an ultrasonic generator, which transmits ultrasonic information based on the received PWM wave data stream. The modules are interconnected via circuitry to transmit data.

[0008] Furthermore, the acquisition module includes two data sources: autonomous signal acquisition and manual signal input. The autonomous signal acquisition method receives signals from environmental sensors (such as smoke sensors and earthquake sensors) in real time and determines whether alarm conditions are met through the autonomous signal acquisition component. This component is deployed in environmental monitoring systems across various application scenarios, such as smart home systems and fire safety systems. It collects environmental information provided by these systems, calculates and generates an output signal, and transmits it to the input conversion module. The manual signal input method provides an operation panel where users select the signal type. After receiving the signal, the manual signal input component transmits the input information to the input conversion module.

[0009] Furthermore, the input conversion module receives input information from the acquisition module. Then, the built-in data selection component selects the corresponding alarm audio data from the built-in audio list based on the input information. This alarm audio data is then transmitted to the signal modulation module via the signal transmission component. The built-in audio list maps input signals to alarm audio data one-to-one. The alarm audio data consists of multiple sets of duration (time) and frequency (freq).

[0010] Furthermore, the signal modulation module modulates the alarm audio data into a specific PWM waveform data stream via a PWM modulation component, enabling the transmitting module to generate a specific alarm mode. The PWM modulation component, by dispersing the effective electrical signal into a discrete form and changing the pulse time width according to the area equivalence rule, effectively obtains the waveform with the required amplitude and frequency to be synthesized. Ultimately, the audio data is converted into a PWM signal represented by high and low levels.

[0011] Furthermore, the transmitting module receives the modulated PWM wave sent by the signal modulation module via a signal generator, and generates a switching signal according to the wave signal. The power amplifier amplifies the power of the switching signal and forwards it to the ultrasonic generator. The ultrasonic generator then transmits ultrasonic information based on the received amplified switching signal.

[0012] Furthermore, the signal types include traffic alarms, fire alarms, earthquake alarms, air raid alarms, and weather alarms.

[0013] Furthermore, the acquisition module also includes a display panel for providing an operation panel for the user.

[0014] Furthermore, the specific implementation process of the PWM modulation component is as follows:

[0015] 1. First, input the duration (time) and frequency (freq), using time as the loop step number of the main loop and freq as the loop step number of the sub-loop;

[0016] 2. Assign freq to i and enter the inner loop;

[0017] 3. The ultrasonic transmitter starts working and lasts for 1 / freq second;

[0018] 4. The ultrasonic transmitter stops working, and i-1 is activated simultaneously;

[0019] 5. Check if i equals 0 (i.e., whether the small loop has ended). If it is not equal to 0, repeat steps 3 to 5; if it equals 0, jump to step 6;

[0020] 6. Check if time equals 0 (i.e., whether the small loop has ended). If it is not equal to 0, jump to step 2; if it equals 0, the transmitting module ends its work.

[0021] Furthermore, the cross-channel ultrasonic alarm system is installed on the vehicle. When installed on the vehicle body of the traffic system, it is located at the car horn. The system receives signals through the autonomous signal acquisition component in the acquisition module. After the sound sensor receives the horn sound, the autonomous signal acquisition component transmits the input signal to the input conversion module. The input conversion module maps the pre-set vehicle horn alarm audio data through the data selection component. The signal transmission component transmits the audio data to the signal modulation module. The signal modulation module uses the PWM modulation component to modulate the audio data into a specific PWM wave data stream. The PWM wave data is transmitted to the transmission module through a circuit link. The transmission module emits the required ultrasonic waves through the ultrasonic generator, causing the active noise-canceling headphones of this invention to generate vehicle horn alarm audio, thereby achieving the alarm purpose.

[0022] Furthermore, when the cross-channel ultrasonic alarm system is installed in a public place, the cross-channel ultrasonic alarm system program is installed in the staff's control room and connected to the public space broadcast alarm system. The transmitting module is installed in an open space conducive to sound wave transmission. The cross-channel ultrasonic alarm system receives signals through the manual input signal component in the acquisition module. When the public space broadcast alarm system has a control console, the cross-channel ultrasonic alarm system provides an operation panel for the user through a software API connection to the control console. When the public space broadcast alarm system does not have a control console, an operation panel is provided for the user through a separate display panel. The user manually selects the alarm signal type to be sent through the operation panel. After receiving the alarm signal type input, the manual input signal component transmits the input to the input conversion module. The input conversion module maps different alarm audio data corresponding to different alarm signal types in advance through the data selection component. The signal transmission component transmits the audio data to the signal modulation module. The signal modulation module uses the PWM modulation component to modulate the audio data into a specific PWM wave data stream and transmits the PWM wave data to the transmitting module through a circuit link. The transmitting module emits the required ultrasonic waves through the ultrasonic generator, so that the active noise-canceling headphones of this invention generate the alarm signal that the user wants to send, thereby achieving the alarm purpose.

[0023] The beneficial effects of this invention are:

[0024] This invention utilizes an ultrasonic modulation method to achieve cross-channel information transmission at the physical level, proposing a novel ultrasonic alarm system for active noise-canceling headphones. This reduces the risk of danger to active noise-canceling headphone users who cannot hear external sounds while in noise-canceling mode.

[0025] This invention uses a programmable ultrasonic module, combined with a PWM modulation component, to realize ultrasonic signal frequency modulation technology, thereby transforming the noise mentioned above into a specific alarm with conventional information, such as an air raid alarm, a fire alarm, or for transmitting specific information. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the cross-channel ultrasonic alarm system of the present invention;

[0027] Figure 2 This is a flowchart illustrating the system usage in an embodiment of the present invention.

[0028] Figure 3 This is a flowchart illustrating the operation of the launch module in an embodiment of the present invention. Detailed Implementation

[0029] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0030] like Figure 1 As shown, a cross-channel ultrasonic alarm system for active noise-canceling headphones includes a data acquisition module, an input conversion module, a signal modulation module, and a transmission module.

[0031] The acquisition module includes an autonomous signal acquisition component, an environmental sensor, and a manual input signal component, used to collect control signals and transmit them to the input conversion module. The input conversion module contains a data selection component and a signal transmission component, used to receive the input information from the acquisition module, convert it into alarm audio data, and then transmit it to the signal modulation module. The signal modulation module includes a PWM modulation component, which modulates the alarm audio data into a specific PWM wave data stream. The transmission module includes a signal generator, a power amplifier, and an ultrasonic generator, which transmits ultrasonic information based on the received PWM wave data stream. The modules are interconnected via circuitry to transmit data.

[0032] The data acquisition module includes two data sources: autonomous signal acquisition and manual signal input. Autonomous signal acquisition receives signals from environmental sensors (such as smoke sensors and earthquake sensors) in real time and determines whether alarm conditions are met through the autonomous signal acquisition component. This component is deployed in environmental monitoring systems across various application scenarios, such as smart home systems and fire safety systems. It collects environmental information provided by these systems, calculates and generates output signals, and transmits them to the input conversion module. Manual signal input provides an operation panel where administrators can manually select the signal type. The manual signal input component receives the signal and transmits it to the input conversion module. Signal types include traffic alarms, fire alarms, earthquake alarms, air raid sirens, weather alarms, and more.

[0033] In one embodiment, the acquisition module further includes a separate display panel for providing an operation panel for the user.

[0034] The input conversion module receives input information from the acquisition module. Then, the built-in data selection component selects the corresponding alarm audio data from the built-in audio list based on the input information. This alarm audio data is then transmitted to the signal modulation module via the signal transmission component. The built-in audio list maps input signals to alarm audio data one-to-one; for example, if the input signal is a fire alarm, the alarm audio data will be the corresponding fire alarm audio data. The alarm audio data consists of multiple sets of duration (time) and frequency (freq).

[0035] The signal modulation module modulates the alarm audio data into a specific PWM waveform data stream using a PWM modulation component, enabling the transmitting module to generate a specific alarm mode. PWM modulation methods are designed to address noise generation methods. This invention targets active noise-canceling headphones that only optimize for low-to-mid-frequency sound waves. Due to limitations such as hardware cost and algorithm design flaws, most headphone active noise-canceling modules neglect high-frequency noise processing. This results in the noise-canceling module failing to generate a response frequency corresponding to the high-frequency audio when receiving high-frequency sound waves. The inverse response audio generated by the noise-canceling module cannot be physically aligned with the original noise, passively resulting in amplitude superposition between the response audio and the original noise, forming a noise with higher loudness and greater impact than the original noise. This invention utilizes this noise phenomenon in conjunction with pulse width modulation to design a PWM modulation component. By dispersing the effective electrical signal into a discrete form and changing the pulse time width according to the area equivalence rule, the desired waveform with the required amplitude and frequency is equivalently obtained. Finally, the audio data is converted into a PWM signal represented by high and low levels.

[0036] The transmitting module receives the modulated PWM wave sent by the signal modulation module via a signal generator and generates a switching signal according to the wave signal. The power amplifier amplifies the power of the switching signal and forwards it to the ultrasonic generator. The ultrasonic generator then transmits ultrasonic information based on the received amplified switching signal.

[0037] Figure 2 This is a flowchart illustrating the system usage in an embodiment of the present invention.

[0038] The core of a cross-channel ultrasonic alarm system lies in its input conversion module and signal modulation module. By changing the duty cycle of the PWM (Power-On Microwave Oven), different frequencies of sound can be output. The alarm audio data received by the PWM modulation component includes the duration (time) and the sound frequency (freq), such as... Figure 3 As shown, the specific implementation process is as follows:

[0039] 1. First, input the duration (time) and frequency (freq), using time as the loop step number of the main loop and freq as the loop step number of the sub-loop;

[0040] 2. Assign freq to i and enter the inner loop;

[0041] 3. The ultrasonic transmitter starts working and lasts for 1 / freq second;

[0042] 4. The ultrasonic transmitter stops working, and i-1 is activated simultaneously;

[0043] 5. Check if i equals 0 (i.e., whether the small loop has ended). If it is not equal to 0, repeat steps 3 to 5; if it equals 0, jump to step 6;

[0044] 6. Check if time equals 0 (i.e., whether the small loop has ended). If it is not equal to 0, jump to step 2; if it equals 0, the transmitting module ends its work.

[0045] The `freq` variable is a counter used to indicate the number of high-to-low level transitions per second, i.e., the frequency. This is the simplest application. In addition, if you want to produce a continuously changing frequency sound like an air raid siren, you can define the interval duration using an array to manually simulate the changing PWM signal, thus achieving continuous pitch variation.

[0046] We conducted experimental evaluations on various active noise-canceling headphones, such as AirPods, Edifier headphones, and Huawei FreeBuds, verifying the feasibility of the system. For the vast majority of active noise-canceling headphones, this system provides good notification functionality, especially for over-ear active noise-canceling headphones.

[0047] This system has a wide range of applications in various places, such as in the transportation sector, as follows.

[0048] Suppose some pedestrians wear active noise-canceling headphones to make phone calls or listen to music. In this case, the sound of vehicle horns is attenuated by the noise-canceling headphones, and pedestrians may encounter danger because they cannot hear the alarm. Using this invention, the device can emit a preset ultrasonic signal simultaneously with detecting a horn sound. Upon receiving this signal, the pedestrian's headphones automatically generate an alarm sound modulated by the ultrasonic signal module, allowing the active noise-canceling headphones to convey a danger signal to the wearer. This method is inexpensive and easy to install on environmental facilities.

[0049] When the cross-channel ultrasonic alarm system is installed on the vehicle body of a traffic system, it is located at the car horn. The system receives signals through an autonomous signal acquisition component in the acquisition module. After the sound sensor receives the horn sound, the autonomous signal acquisition component transmits the input signal to the input conversion module. The input conversion module maps pre-set vehicle horn alarm audio data through a data selection component. The signal transmission component then transmits the audio data to the signal modulation module. The signal modulation module uses a PWM modulation component to modulate the audio data into a specific PWM wave data stream, which is then transmitted to the transmission module via a circuit link. The transmission module emits the required ultrasonic waves through an ultrasonic generator, causing the active noise-canceling headphones targeted by this invention to generate vehicle horn alarm audio, thereby achieving the alarm purpose.

[0050] Because the directional nature of the ultrasonic module causes the alarm sound to be at different volumes in the two earpieces, this characteristic can be used by pedestrians to determine the direction of oncoming traffic, as vehicles often approach from the direction of higher volume in the earpiece. Pedestrians can quickly determine that the oncoming vehicle is coming from the left using this system. Simultaneously, due to the Doppler effect, the wavelength or frequency changes with the relative motion between the observer and the sound source, similar to a siren. When we use the ultrasonic module to generate a uniformly spaced pulse alarm sound, the wavelength and frequency of the audio signal generated in the active noise-canceling earpieces will change with the distance between the car and the earpiece wearer. In this case, it can help the earpiece wearer use the Doppler effect to determine whether the vehicle is approaching or leaving, thus mitigating traffic risks from another perspective.

[0051] Installing this device can not only provide vehicle alarm information, but also provide pedestrians with multi-dimensional information such as vehicle distance and direction.

[0052] When the device is installed near static reference objects such as streetlights and zebra crossings in the environment, it can also send the same alarm information. Although it can provide fewer information dimensions compared to installing it on a vehicle, its advantages are that the number of installations required is low, the cost is low, and it has strong scalability.

[0053] This system also has many more extended functions. Examples are as follows.

[0054] In fire warning systems, for example, when headphone wearers are in public spaces such as shopping malls, the active noise-canceling headphones can easily block out ambient sounds, causing them to ignore environmental noise. This is especially true when a shopping mall is large and has low foot traffic, as malls often use loudspeakers to broadcast warnings to evacuate people. If these warnings are blocked by the active noise-canceling headphones, and mobile apps cannot provide such information to warn of emergencies, the headphone wearer will be in grave danger. In such cases, adding an ultrasonic alarm system to the mall's broadcasting system allows the active noise-canceling headphones to emit a significant alarm, effectively alerting the wearer to the danger and preventing them from being caught in a fire. Similar scenarios exist for other types of disaster risks.

[0055] When a cross-channel ultrasonic alarm system is installed in a public space, the system program should be installed in the staff's control room and connected to the public space broadcast alarm system. The transmitting module should be installed in an open space conducive to sound wave transmission, such as next to the broadcasting device. The cross-channel ultrasonic alarm system receives signals through the manual input signal component in the acquisition module. When the public space broadcast alarm system has a control console, the cross-channel ultrasonic alarm system provides an operation panel for users by connecting to the control console via a software API. When the public space broadcast alarm system does not have a control console, an operation panel is provided for users through a separate display panel. Users manually select the alarm signal type to be sent through the operation panel. After receiving the alarm signal type input, the manual input signal component transmits the input to the input conversion module. The input conversion module maps different alarm audio data corresponding to different alarm signal types in advance through the data selection component. The signal transmission component transmits the audio data to the signal modulation module. The signal modulation module uses the PWM modulation component to modulate the audio data into a specific PWM wave data stream and transmits the PWM wave data to the transmitting module through a circuit link. The transmitting module emits the required ultrasonic waves through the ultrasonic generator, causing the active noise-canceling headphones of this invention to generate the alarm signal desired by the user, thereby achieving the alarm purpose.

[0056] This system design overcomes the shortcomings of current mainstream alarm information, which is easily filtered by active noise-canceling headphones. At the same time, it does not rely excessively on the technology of the headphones and the app themselves. It can be directly installed by the alarm unit or used as an auxiliary device in traffic systems and environmental equipment. It provides a way for the outside world to send alarms directly to users of noise-canceling headphones, thus improving the current alarm system.

[0057] 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. Those skilled in the art can make various substitutions or modifications to these described embodiments without departing from the inventive concept, and all such substitutions or modifications should be considered within the scope of protection of the present invention.

[0058] The parts of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A cross-channel ultrasonic alert system for active noise reducing headphones, characterized in that, It includes a data acquisition module, an input conversion module, a signal modulation module, and a transmission module; The acquisition module includes an autonomous signal acquisition component, an environmental sensor, and a manual input signal component, used to collect control signals and transmit them to the input conversion module. The input conversion module includes a data selection component and a signal transmission component, used to receive the input information transmitted by the acquisition module, convert it into alarm audio data, and transmit it to the signal modulation module. The signal modulation module includes a PWM modulation component, which modulates the alarm audio data into a set PWM wave data stream. The transmission module includes a signal generator, a power amplifier, and an ultrasonic generator, which transmits ultrasonic information based on the received PWM wave data stream. The modules are connected by circuitry to transmit data. The signal modulation module modulates the alarm audio data into a set PWM wave data stream through the PWM modulation component, enabling the transmitting module to generate the set alarm mode. The PWM modulation component, by dispersing the effective electrical signal into a discrete form and changing the pulse time width according to the area equivalence law, equivalently obtains the waveform with the required amplitude and frequency to be synthesized. Finally, the audio data is converted into a PWM signal represented by high and low levels.

2. A cross-channel ultrasonic alert system for active noise cancelling headphones according to claim 1, wherein, The acquisition module includes two data sources: autonomous signal acquisition and manual signal input. The autonomous signal acquisition method receives signals from environmental sensors in real time and uses the autonomous signal acquisition component to determine if alarm conditions are met. This component is deployed in environmental monitoring systems across various application scenarios. It collects environmental information provided by the monitoring system, calculates and generates an output signal, and transmits it to the input conversion module. The manual signal input method provides an operation panel where users can select the signal type. After receiving the signal, the manual signal input component transmits the input information to the input conversion module.

3. A cross-channel ultrasonic alarm system for active noise-canceling headphones according to claim 2, characterized in that, The input conversion module receives input information from the acquisition module. Then, the built-in data selection component selects alarm audio data corresponding to the input information from the built-in audio list, and transmits the alarm audio data to the signal modulation module through the signal transmission component. The built-in audio list maps input signals to alarm audio data; the alarm audio data consists of multiple sets of duration (time) and sound frequency (freq).

4. A cross-channel ultrasonic alert system for active noise cancelling headphones according to claim 3, wherein, The transmitting module receives the modulated PWM wave sent by the signal modulation module through the signal generator, and generates a switching signal according to the modulated PWM wave signal; the power amplifier amplifies the power of the switching signal and forwards it to the ultrasonic generator; the ultrasonic generator sends ultrasonic information according to the received amplified switching signal.

5. A cross-channel ultrasonic alert system for active noise cancelling headphones according to claim 2, wherein, The signal types mentioned include traffic alarms, fire alarms, earthquake alarms, air raid alarms, and weather alarms.

6. A cross-channel ultrasonic alarm system for active noise-canceling headphones according to claim 1 or 2, characterized in that, The acquisition module also includes a display panel for providing an operation panel for the user.

7. A cross-channel ultrasonic alarm system for active noise-canceling headphones according to claim 3, characterized in that, The specific implementation process of the PWM modulation component is as follows:

1. First, input the duration (time) and frequency (freq), using time as the loop step number of the main loop and freq as the loop step number of the sub-loop; 2. Assign freq to i and enter the inner loop; 3. The ultrasonic transmitter starts working and lasts for 1 / freq second; 4. The ultrasonic transmitter stops working, and i-1 is activated simultaneously; 5. Check if i equals 0; if not, repeat steps 3 to 5; if equal to 0, jump to step 6.

6. Check if time equals 0; If the value is not equal to 0, proceed to step 2; if the value is equal to 0, the transmitting module will cease operation.

8. A cross-channel ultrasonic alarm system for active noise-canceling headphones according to any one of claims 1-4, characterized in that, The cross-channel ultrasonic alarm system is installed on the vehicle. When the cross-channel ultrasonic alarm system is installed on the vehicle body of the traffic system, it is located at the car horn. The system receives signals through the autonomous signal acquisition component in the acquisition module. After the sound sensor receives the horn sound, the autonomous signal acquisition component transmits the input signal to the input conversion module. The input conversion module maps pre-set vehicle horn alarm audio data through the data selection component, and the signal transmission component transmits the audio data to the signal modulation module. The signal modulation module uses a PWM modulation component to modulate the audio data into a set PWM wave data stream. The PWM wave data is then transmitted to the transmitting module via a circuit link. The transmitting module emits the required ultrasonic waves through an ultrasonic generator, causing the targeted active noise-canceling headphones to generate a vehicle horn alarm audio, thereby achieving the alarm purpose.

9. A cross-channel ultrasonic alarm system for active noise-canceling headphones according to any one of claims 1-4, characterized in that, When the cross-channel ultrasonic alarm system is installed in a public place, the cross-channel ultrasonic alarm system program is installed in the staff's control room and connected to the public space broadcast alarm system. The transmitting module is installed in an open space that facilitates sound wave transmission. The cross-channel ultrasonic alarm system receives signals through the manual input signal component in the acquisition module. When the public space broadcast alarm system has a control console, the cross-channel ultrasonic alarm system connects to the control console through a software API to provide users with an operation panel; when the public space broadcast alarm system does not have a control console, it provides users with an operation panel through a separate display panel. Users can manually select the type of alarm signal to be sent through the operation panel. After the manual input signal component receives the alarm signal type input, it will pass the input to the input conversion module. The input conversion module maps different alarm audio data corresponding to different alarm signal types in advance through the data selection component, and the signal transmission component transmits the audio data to the signal modulation module. The signal modulation module uses a PWM modulation component to modulate the audio data into a set PWM wave data stream. The PWM wave data is then transmitted to the transmitting module via a circuit link. The transmitting module emits the required ultrasonic waves through an ultrasonic generator, causing the targeted active noise-canceling headphones to generate the alarm signal that the user wants to send, thereby achieving the alarm purpose.

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