Method and apparatus for sending or decoding acoustic wave signal

Abstract

The present application relates to the field of wireless communications, and in particular to a method and apparatus for sending or decoding an acoustic wave signal. In acoustic wave communication, the relative movement of a sending end and a receiving end may generate a strong Doppler effect, which causes severe interference to the acoustic wave communication. In the present application, a sending end sends a probe signal when sending a communication signal, and the sending frequency of the probe signal is information that is known to a receiving end. The receiving end can estimate a frequency shift on the basis of the sending frequency and a receiving frequency of the probe signal. Since the communication signal and the probe signal are sent at the same time or at a relatively short interval, and the impacts of the Doppler effect on the communication signal and the probe signal are almost the same, the frequency shift can be used to correct a receiving frequency of the communication signal, so as to reduce the interference with the acoustic wave communication caused by the Doppler effect.

Description

Methods and apparatus for transmitting or decoding acoustic signals

[0001] This application claims priority to Chinese patent application filed on August 26, 2024, with application number 202411181311.2 and entitled "Method and apparatus for transmitting or decoding acoustic signals", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of wireless communication, specifically to a method and apparatus for transmitting acoustic signals, and a method and apparatus for decoding acoustic signals. Background Technology

[0003] Acoustic communication is a wireless communication technology that uses sound waves as a carrier to transmit information. For example, the transmitting end encodes and modulates the information, transmits it through sound waves, and the receiving end demodulates and decodes the received sound waves to obtain the information.

[0004] The Doppler effect is the phenomenon that when there is relative motion between the wave source and the observer, the frequency of the wave received by the observer is different from the frequency of the wave emitted by the wave source.

[0005] Because the speed of sound waves is much slower than the speed of electromagnetic waves, if there is relative motion between the transmitting and receiving ends, the Doppler effect caused by this relative motion on sound waves is much stronger than the Doppler effect caused by relative motion on electromagnetic waves. A strong Doppler effect can cause serious interference to sound wave communication, and how to reduce this interference is a problem that needs to be solved. Summary of the Invention

[0006] Embodiments of this application provide a method, apparatus, computer-readable storage medium, and computer program product for transmitting or decoding acoustic signals, which can reduce the interference of the Doppler effect on acoustic communication.

[0007] In a first aspect, embodiments of this application provide a method for transmitting an acoustic signal. The subject executing this method may be a transmitting end, which may be an electronic device or a chip applied to an electronic device. The method includes: determining a first frequency; determining a second frequency, the second frequency being a preset transmission frequency; transmitting a first acoustic signal according to the first frequency; and transmitting a second acoustic signal according to the second frequency, the second acoustic signal being used to correct the receiving frequency of the first acoustic signal.

[0008] Since the second frequency is a preset transmission frequency, the receiving end can determine the transmission frequency of the second acoustic signal. Therefore, after receiving the second acoustic signal, the receiving end can determine the Doppler frequency shift of the second acoustic signal, i.e., the first frequency shift, based on the receiving and transmission frequencies. Typically, the transmission interval between the first and second acoustic signals is not too long (e.g., the difference between the transmission times of the first and second acoustic signals is less than or equal to a time threshold). The Doppler effects of the first and second acoustic signals are also similar. Therefore, the first frequency shift can be used to correct the receiving frequency of the first acoustic signal, thereby reducing the interference of the Doppler effect on acoustic communication.

[0009] In an optional implementation of the first aspect, determining the second frequency includes: determining the second frequency from a preset frequency set based on the first frequency, wherein the degree of crosstalk between the second frequency and the first frequency satisfies communication requirements.

[0010] There may be crosstalk between the second frequency and the first frequency. The transmitter can select a frequency with a satisfactory level of crosstalk from a preset frequency set, such as the second frequency, based on the currently used communication frequency (e.g., the first frequency), thus flexibly adapting to different communication scenarios.

[0011] In an alternative embodiment of the first aspect, the second acoustic signal is transmitted simultaneously with the first acoustic signal.

[0012] Since the relative motion rates of the transmitting and receiving ends may differ at different times, the Doppler frequency shift may also differ at different times. In this embodiment, the second acoustic signal is transmitted simultaneously with the first acoustic signal, which can reduce the difference in the Doppler frequency shift between the two acoustic signals, thereby improving the correction accuracy of the received frequency of the first acoustic signal.

[0013] In an alternative implementation of the first aspect, the second acoustic signal carries preset information.

[0014] Other acoustic signals may exist in the area where the transmitter and receiver are located. Preset information can help the receiver correctly identify the second acoustic signal, thereby improving the accuracy of the correction of the receiving frequency of the first acoustic signal.

[0015] In an optional embodiment of the first aspect, the method further includes: determining a third frequency, the third frequency being a preset transmission frequency; and transmitting a third acoustic signal according to the third frequency, the third acoustic signal being used to correct the reception frequency of the first acoustic signal.

[0016] In some cases, the second acoustic signal may be interfered with by other acoustic signals or obstructions, leading to a large error in the Doppler frequency shift calculated based on the second acoustic signal. In this embodiment, the transmitting end sends multiple acoustic signals to correct the receiving frequency of the first acoustic signal, and the receiving end uses these multiple acoustic signals to calculate the Doppler frequency shift, which can reduce the calculation error of the Doppler frequency shift.

[0017] In an optional embodiment of the first aspect, the method further includes: determining a fourth frequency; determining a fifth frequency, the fifth frequency being a preset transmission frequency; transmitting a fourth acoustic signal according to the fourth frequency; and transmitting a fifth acoustic signal according to the fifth frequency, the fifth acoustic signal being used to correct the receiving frequency of the fourth acoustic signal.

[0018] In some cases, acoustic signals may be interfered with by other acoustic signals or obstructions, leading to a deterioration in the communication quality of individual acoustic signals. In this embodiment, the transmitting end sends multiple acoustic signals, so even if some acoustic signals are interfered with, the receiving end can still use the undisturbed acoustic signals for communication, thereby improving the reliability of acoustic communication.

[0019] In an optional embodiment of the first aspect, the difference between the fifth frequency and the fourth frequency is less than the difference between the second frequency and the fourth frequency, and / or the difference between the fifth frequency and the first frequency is greater than the difference between the second frequency and the first frequency.

[0020] The Doppler frequency shift of sound wave signals varies in different frequency bands. Using sound wave signals with similar frequency bands to correct the receiving frequency can improve the accuracy of the receiving frequency correction.

[0021] In an optional implementation of the first aspect, there is a preset association between the fifth frequency and the frequency band where the fourth frequency is located, and / or, there is a preset association between the second frequency and the frequency band where the first frequency is located.

[0022] Frequency bands with close Doppler shifts and / or low crosstalk can be determined based on prior experimental results or a priori knowledge. For example, if the Doppler shift of the fifth frequency is close to that of the fourth frequency, the correlation between the frequency band containing the fifth frequency and the frequency band containing the fourth frequency can be pre-defined. If the crosstalk between the second frequency and the first frequency is low, the correlation between the frequency band containing the second frequency and the frequency band containing the first frequency can be defined. In this way, the transmitting end and / or receiving end can determine the fifth frequency and the second frequency without performing complex calculations, thereby reducing the computational resource overhead of correcting the receiving frequency.

[0023] In an optional implementation of the first aspect, the method further includes: when the first acoustic signal fails to be received, outputting first information, the first information prompting the user to keep the transmitting end and receiving end of the first acoustic signal relatively stationary, and / or, the first information prompting the user to keep the transmitting end and receiving end of the first acoustic signal unobstructed.

[0024] Based on the first piece of information, the success rate of acoustic communication between the sending and receiving ends can be improved.

[0025] In an optional implementation of the first aspect, the method further includes: receiving second information indicating that the first acoustic signal was successfully received; and storing the first frequency based on the second information.

[0026] After successfully decoding the first acoustic signal, the receiving end can send the reception result back to the sending end via the second information. Upon receiving the second information, the sending end stores the first frequency, which can then be used directly to communicate with the receiving end without attempting other frequencies, thus improving the efficiency of subsequent acoustic communication.

[0027] In an optional embodiment of the first aspect, the method further includes: receiving third information, the third information indicating a receiving end of the first acoustic signal; and storing information of the receiving end based on the third information.

[0028] In some scenarios, the transmitter may communicate with multiple receivers via sound waves. After successfully decoding the first sound wave signal, the receiver of the first sound wave signal can send third information indicating itself to the transmitter, thereby enabling the transmitter to determine the receiver corresponding to the first frequency.

[0029] In an optional implementation of the first aspect, the method further includes: sending device information of the receiving end and a first frequency to the server.

[0030] In this embodiment, when other devices need to communicate with the receiver via sound waves, the other devices can query the server for the sound wave communication frequency used by the receiver based on the receiver's device information, such as the first frequency. The first frequency is a verified frequency that can be used directly, and other devices do not need to try other frequencies, thereby improving the efficiency of sound wave communication.

[0031] Secondly, embodiments of this application provide a method for decoding acoustic signals. The executing entity of this method can be a receiving end, which can be an electronic device or a chip applied to an electronic device. The method includes: receiving a first acoustic signal; receiving a second acoustic signal according to a second frequency, wherein the second frequency is a preset transmission frequency; determining a receiving frequency of the second acoustic signal; determining a first frequency shift according to the receiving frequency of the second acoustic signal and the second frequency; and decoding the first acoustic signal according to the first frequency shift.

[0032] Since the second frequency is a preset transmission frequency, the receiving end can determine the transmission frequency of the second acoustic signal. Therefore, after receiving the second acoustic signal, the receiving end can determine the Doppler frequency shift, i.e., the first frequency shift, based on the receiving and transmission frequencies of the second acoustic signal. Typically, the transmission interval between the first and second acoustic signals is not too long (e.g., the difference between the transmission times of the first and second acoustic signals is less than or equal to a time threshold). The Doppler effects of the first and second acoustic signals are also similar. Therefore, the first frequency shift can be used to correct the receiving frequency of the first acoustic signal, thereby reducing the interference of the Doppler effect on acoustic communication.

[0033] In an alternative embodiment of the second aspect, the second acoustic signal is received simultaneously with the first acoustic signal.

[0034] Since the relative motion rates of the transmitting and receiving ends may differ at different times, the Doppler frequency shift may also differ at different times. In this embodiment, the second acoustic signal is transmitted simultaneously with the first acoustic signal, which can reduce the difference in the Doppler frequency shift between the two acoustic signals, thereby improving the correction accuracy of the received frequency of the first acoustic signal.

[0035] In an alternative implementation of the second aspect, the second acoustic signal carries preset information.

[0036] Other acoustic signals may exist in the area where the transmitter and receiver are located. Preset information can help the receiver correctly identify the second acoustic signal, thereby improving the accuracy of the correction of the receiving frequency of the first acoustic signal.

[0037] In an optional embodiment of the second aspect, the method further includes: receiving a third acoustic signal according to a third frequency, the third frequency being a preset transmission frequency; determining a receiving frequency of the third acoustic signal; determining a second frequency shift according to the receiving frequency of the third acoustic signal and the third frequency; and decoding a first acoustic signal according to a first frequency shift, including: decoding the first acoustic signal according to the first frequency shift and the second frequency shift.

[0038] In some cases, the second acoustic signal may be interfered with by other acoustic signals or obstructions, leading to a large error in the Doppler frequency shift calculated based on the second acoustic signal. In this embodiment, the transmitting end sends multiple acoustic signals to correct the receiving frequency of the first acoustic signal, and the receiving end uses these multiple acoustic signals to calculate the Doppler frequency shift, which can reduce the calculation error of the Doppler frequency shift.

[0039] In an optional embodiment of the second aspect, the method further includes: receiving a fourth acoustic signal; receiving the fifth acoustic signal according to a fifth frequency, wherein the fifth frequency is a preset transmission frequency; determining the receiving frequency of the fifth acoustic signal; determining a third frequency shift according to the receiving frequency of the fifth acoustic signal and the fifth frequency; and decoding the fourth acoustic signal according to the third frequency shift.

[0040] In some cases, acoustic signals may be interfered with by other acoustic signals or obstructions, leading to a deterioration in the communication quality of individual acoustic signals. In this embodiment, the transmitting end sends multiple acoustic signals, so even if some acoustic signals are interfered with, the receiving end can still use the undisturbed acoustic signals for communication, thereby improving the reliability of acoustic communication.

[0041] In an optional implementation of the second aspect, the method further includes: when the first acoustic signal fails to be received, outputting fourth information, the fourth information prompting the user to keep the transmitting end and receiving end of the first acoustic signal relatively stationary, and / or, the fourth information prompting the user to keep the transmitting end and receiving end of the first acoustic signal unobstructed.

[0042] Based on the fourth piece of information, the success rate of acoustic communication between the transmitter and receiver can be improved.

[0043] In an optional implementation of the second aspect, the method further includes: when the first acoustic signal is successfully received, sending second information, the second information indicating that the first acoustic signal has been successfully received.

[0044] After successfully decoding the first acoustic signal, the receiving end can send the reception result back to the sending end via the second information. Upon receiving the second information, the sending end stores the first frequency, which can then be used directly to communicate with the receiving end without attempting other frequencies, thus improving the efficiency of subsequent acoustic communication.

[0045] In an alternative implementation of the second aspect, the method further includes: sending third information, the third information indicating the receiving end of the first acoustic signal.

[0046] In some scenarios, the transmitter may communicate with multiple receivers via sound waves. After successfully decoding the first sound wave signal, the receiver of the first sound wave signal can send third information indicating itself to the transmitter, thereby enabling the transmitter to determine the receiver corresponding to the first frequency.

[0047] In an optional implementation of the second aspect, the method further includes: obtaining a first frequency from the transmitting end of the first acoustic signal; and sending device information of the receiving end and the first frequency to the server.

[0048] In this embodiment, when other devices need to communicate with the receiver via sound waves, the other devices can query the server for the sound wave communication frequency used by the receiver based on the receiver's device information, such as the first frequency. The first frequency is a verified frequency that can be used directly, and other devices do not need to try other frequencies, thereby improving the efficiency of sound wave communication.

[0049] Thirdly, embodiments of this application provide an apparatus for transmitting acoustic signals. The apparatus may include a processing unit and a transmitting unit for performing any of the methods described in the first aspect and its optional embodiments.

[0050] Fourthly, embodiments of this application provide an apparatus for decoding acoustic signals. The apparatus may include a processing unit and a receiving unit for performing any of the methods described in the second aspect and its optional embodiments.

[0051] Fifthly, embodiments of this application provide an apparatus for transmitting acoustic signals. This apparatus may be an electronic device or a chip applied to an electronic device. The apparatus may include a processor for executing any of the methods described in the first aspect and its optional embodiments.

[0052] Optionally, when the device is an electronic device, the processor is, for example, a central processor unit (CPU), an application-specific integrated circuit (ASIC), or a field-programmable gate array (FPGA); when the device is a chip, the processor is, for example, a core, which may include at least one execution unit, such as an arithmetic and logic unit (ALU).

[0053] Optionally, the device may also include a transceiver. When the device is an electronic device, the transceiver may be a transceiver circuit, a speaker, etc.; when the device is a chip, the transceiver may be an input / output interface, pins, circuits, etc.

[0054] Optionally, the device may further include a memory for storing computer programs or instructions, which the processor executes to cause the device to perform any of the methods described in the first aspect and its optional embodiments. When the device is an electronic device, the memory may be a read-only memory, random access memory, etc.; when the device is a chip, the memory may be a register, cache, etc.

[0055] Sixthly, embodiments of this application provide an apparatus for decoding acoustic signals. This apparatus may be an electronic device or a chip applied to an electronic device. The apparatus may include a processor for executing any of the methods described in the second aspect and its optional embodiments.

[0056] Optionally, when the device is an electronic device, the processor is, for example, a CPU, an ASIC, or an FPGA; when the device is a chip, the processor is, for example, a core, which may include at least one execution unit, such as an ALU.

[0057] Optionally, the device may also include a transceiver. When the device is an electronic device, the transceiver may be a transceiver circuit, a microphone, etc.; when the device is a chip, the transceiver may be an input / output interface, pins, circuits, etc.

[0058] Optionally, the device may further include a memory for storing computer programs or instructions, which the processor executes to cause the device to perform any of the methods described in the second aspect and its optional embodiments. When the device is an electronic device, the memory may be a read-only memory, random access memory, etc.; when the device is a chip, the memory may be a register, cache, etc.

[0059] In a seventh aspect, embodiments of this application provide a communication system comprising: the means for transmitting acoustic signals as described in the third aspect, and the means for decoding acoustic signals as described in the fourth aspect; or, the means for transmitting acoustic signals as described in the fifth aspect, and the means for decoding acoustic signals as described in the sixth aspect.

[0060] Eighthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed on a device, causes the device to perform: any of the methods in the first aspect and its optional embodiments, or any of the methods in the second aspect and its optional embodiments.

[0061] Ninthly, embodiments of this application provide a computer program product comprising: computer program code or computer program instructions, which, when executed by a device, cause the device to perform: any method of the first aspect and its optional embodiments, or any method of the second aspect and its optional embodiments. Attached Figure Description

[0062] Figure 1 is a schematic diagram of an acoustic communication system provided in an embodiment of this application;

[0063] Figure 2 is a schematic diagram of another acoustic communication system provided in an embodiment of this application;

[0064] Figure 3 is a schematic diagram of an acoustic communication principle provided by an embodiment of this application;

[0065] Figure 4 is a schematic diagram of an acoustic communication method provided in an embodiment of this application;

[0066] Figures 5 to 8 are schematic diagrams of several methods for triggering the sending end 110 to execute S410 according to embodiments of this application.

[0067] Figure 9 is a schematic diagram of a first acoustic signal and a second acoustic signal provided in an embodiment of this application;

[0068] Figure 10 is a schematic diagram of an interface when the receiver 120 receives the first acoustic signal according to an embodiment of this application;

[0069] Figure 11 is another schematic diagram of the interface when the receiver 120 receives the first acoustic signal according to an embodiment of this application;

[0070] Figure 12 is a schematic diagram of a method for correcting the receiving frequency of a first acoustic signal using multiple acoustic signals, provided in an embodiment of this application.

[0071] Figure 13 is a schematic diagram of a third acoustic signal provided in an embodiment of this application;

[0072] Figure 14 is a schematic diagram of a communication method using multiple acoustic signals provided in an embodiment of this application;

[0073] Figure 15 is a schematic diagram of the fourth and fifth acoustic signals provided in an embodiment of this application;

[0074] Figure 16 is a schematic diagram of an interface for the first information provided in an embodiment of this application;

[0075] Figure 17 is a schematic diagram of an interface for the fourth information provided in an embodiment of this application;

[0076] Figure 18 is a schematic diagram of a feedback method in an acoustic wave communication method provided in an embodiment of this application;

[0077] Figure 19 is a schematic diagram of an application scenario of the acoustic communication method provided in the embodiments of this application;

[0078] Figure 20 is a schematic diagram of another application scenario of the acoustic communication method provided in the embodiments of this application;

[0079] Figure 21 is a schematic diagram of another application scenario of the acoustic communication method provided in the embodiments of this application;

[0080] Figure 22 is a schematic diagram of an acoustic communication device provided in an embodiment of this application;

[0081] Figure 23 is a schematic diagram of another acoustic communication device provided in an embodiment of this application. Detailed Implementation

[0082] To facilitate understanding of the technical solution of this application, a brief introduction to some terms and concepts involved in this application will be given first. It should be noted that the descriptions of these terms and concepts are illustrative rather than limiting.

[0083] Sound waves are the form of sound propagation. Sound waves originate from a transmitting end and propagate outwards through a medium. The frequency of a sound wave refers to the number of vibrations of a particle in a wave train per unit time, and can be described in Hertz (Hz). Based on different frequencies, sound waves can be classified into the following categories:

[0084] Sound waves with frequencies below 20 Hz are called infrasound; sound waves with frequencies between 20 Hz and 20 kHz are called audible sound; and sound waves with frequencies above 20 kHz are called ultrasound.

[0085] Ultrasound is a sound wave with a frequency higher than the upper limit of human hearing, with most commonly used ultrasound frequencies above 20 kHz. It is used in a variety of ways for communication, including sonar, medical imaging, and even security systems. In communication, ultrasound is used for various purposes such as distance measurement, object detection, and data transmission. In data transmission, ultrasound can act as a carrier wave to wirelessly transmit information over short distances. This technology is commonly used in wireless payment systems, mobile messaging, and location-based services. The extensive applications of ultrasound technology in modern communication systems make it an important and versatile tool in modern communication technology. In summary, ultrasound is a versatile technology with wide-ranging applications in communication.

[0086] Figure 1 is a schematic diagram of an acoustic communication system provided in an embodiment of this application.

[0087] The acoustic communication system 100 includes a transmitter 110 and a receiver 120. The transmitter 110 and receiver 120 can be mobile phones, foldable electronic devices, tablets, desktop computers, laptops, handheld computers, notebook computers, ultra-mobile personal computers (UMPCs), netbooks, cellular phones, personal digital assistants (PDAs), augmented reality (AR) devices, virtual reality (VR) devices, artificial intelligence (AI) devices, wearable devices, in-vehicle devices, smart home devices, or smart city devices. The embodiments of this application do not impose any special limitations on the specific types of the transmitter 110 and receiver 120.

[0088] Transmitter 110 is a device with sound wave transmission capability, capable of sending sound wave signals to receiver 120. For example, transmitter 110 may include a processor, an audio module, and a speaker. The processor outputs digital audio signals, the audio module converts the digital audio signals into analog audio signals, and the speaker converts the analog audio signals into sound wave signals for transmission.

[0089] The processor, audio module, and speaker of the transmitter 110 can be integrated or separate.

[0090] For example, the processor, audio module, and speaker of the transmitter 110 are integrated, and the processor, audio module, and speaker can transmit signals through an internal interface.

[0091] For example, the audio module of the transmitter 110 is integrated with the speaker. The processor transmits digital audio signals to the audio module via wireless connection such as Bluetooth, or the processor transmits digital audio signals to the audio module via wired connection such as a universal serial bus (USB) interface.

[0092] For example, the processor of the transmitter 110 is integrated with the audio module. The audio module transmits analog audio signals to the speaker via wireless connection such as Bluetooth, or via wired connection such as USB interface.

[0093] Receiver 120 is a device with sound wave receiving capability, capable of receiving sound wave signals from transmitter 110. For example, receiver 120 may include a processor, an audio module, and a microphone. The microphone is used to receive the sound wave signal and convert it into an analog audio signal, the audio module is used to convert the analog audio signal into a digital audio signal, and the processor processes the digital audio signal.

[0094] The processor, audio module, and microphone of the receiver 120 can be integrated or separate.

[0095] For example, the processor, audio module, and microphone of receiver 120 are integrated, and the processor, audio module, and microphone can transmit signals through an internal interface.

[0096] For example, the audio module of the receiver 120 is integrated with the microphone. The audio module transmits digital audio signals to the processor via wireless connection such as Bluetooth, or via wired connection such as USB interface.

[0097] For example, the processor of receiver 120 is integrated with the audio module. The microphone transmits analog audio signals to the audio module via wireless connection such as Bluetooth, or the microphone transmits analog audio signals to the audio module via wired connection such as USB interface.

[0098] The transmitter 110 and receiver 120 may also have other functions, such as Bluetooth, Wi-Fi and Star Flash. The embodiments of this application do not limit the other functions of the transmitter 110 and receiver 120.

[0099] The acoustic communication system 100 shown in Figure 1 includes one transmitter and one receiver. Optionally, the acoustic communication system 100 may also include more transmitters and receivers. For example, the acoustic communication system 100 may also include one transmitter and two receivers, or two transmitters and one receiver, or two transmitters and two receivers. The embodiments of this application do not limit the number of transmitters and receivers in the acoustic communication system 100.

[0100] Figure 2 is a schematic diagram of another acoustic communication system provided in an embodiment of this application.

[0101] The acoustic communication system 200 includes a transmitter 110, a receiver 120, a server 130, and a router 140. The transmitter 110 and receiver 120 in Figure 2 are the same as those in Figure 1, and will not be described again.

[0102] Server 130 can be a home server, such as a home storage device. Server 130 can also be a commercial server, such as a tower server, blade server, or rack server. Furthermore, server 130 can also be a virtual server, such as a virtual machine (VM) or a container (Docker). The embodiments of this application do not limit the specific type of server 130.

[0103] The transmitter 110 and receiver 120 can communicate with the server 130 via the Wi-Fi network provided by the router 140, wherein the router 140 and the server 130 can be connected via optical fiber. The dashed arrows in Figure 2 indicate the communication links.

[0104] Sender 110 can send data to server 130, which can store the data locally and send it to receiver 120 when receiver 120 requests it. Receiver 120 can also send data to server 130, which can store the data locally and send it to sender 110 when receiver 110 requests it.

[0105] The following describes an acoustic communication principle provided by an embodiment of this application.

[0106] As shown in Figure 3, A is a bit stream obtained after encoding, mapping and other operations of source information (such as pictures, text or videos). The transmitter 110 performs serial-to-parallel conversion on A to obtain N bit streams. Then, the multiple bit streams are modulated onto N carriers (f_1 to f_N) to generate N modulation symbols. The N modulation symbols are spliced ​​to generate signal S(t), and then the transmitter 110 transmits S(t).

[0107] Due to factors such as noise that may exist in the channel, the signal received by receiver 120 is S'(t). After filtering and other processing of S'(t), receiver 120 uses Fast Fourier Transform (FFT) to decode it, obtaining N frequency estimates, i.e., f_1 ^ ~f_N ^ Subsequently, the receiver 120 uses these N frequency estimates to demodulate the filtered S'(t). The demodulated signal is then converted from parallel to serial to obtain bit stream A. The receiver 120 can perform inverse mapping, decoding, and other operations on bit stream A to obtain the aforementioned source information.

[0108] The acoustic communication principle shown in Figure 3 is an example and not a limitation; other acoustic communication methods are also applicable to the embodiments of this application.

[0109] When the transmitter 110 and receiver 120 are relatively stationary, the frequency estimate determined based on S'(t) is not significantly different from the carrier frequency, and the receiver 120 can correctly decode the source information. However, if there is relative motion between the transmitter 110 and receiver 120, S'(t) is affected by the Doppler effect, and the frequency estimate determined based on S'(t) differs significantly from the carrier frequency, making it impossible to decode the source information based on the frequency estimate.

[0110] The following describes an acoustic communication method provided by an embodiment of this application.

[0111] Figure 4 is a schematic diagram of an acoustic communication method 400 provided in an embodiment of this application. The method 400 can be executed by an electronic device or a chip applied to an electronic device. The following description uses a transmitting end 110 and a receiving end 120 as examples.

[0112] As shown in Figure 4, method 400 includes:

[0113] S410, transmitter 110 determines the first frequency.

[0114] The first frequency is the carrier frequency used by the transmitter 110 and receiver 120 for acoustic communication. The first frequency can be an ultrasonic frequency, a subsonic ultrasonic frequency (e.g., a frequency in the 16kHz to 20kHz band), or a frequency in other frequency bands supported by the transmitter 110 and receiver 120. This application does not limit the specific value of the first frequency.

[0115] The transmitter 110 can execute S410 according to the user's instructions. Figures 5 to 8 are schematic diagrams of several methods for triggering the transmitter 110 to execute S410 according to embodiments of this application.

[0116] As shown in Figure 5, when a user clicks the "Screen Casting" icon on the interface of the transmitter 110, the transmitter 110 enters the screen casting settings page shown in Figure 6. Optionally, the user can also use a remote control or other device to click the "Screen Casting" icon on the interface of the transmitter 110.

[0117] The transmitter 110 displays the interface shown in Figure 6 based on user triggers. On this interface, the user can select the connection method and connection target. The "Connection Method" option indicates which method the transmitter 110 uses to establish a connection, and the "Connection Target" option indicates which devices the transmitter 110 connects to. Within the sub-options of the "Connection Target" option, the "Local Devices" option represents devices that have established a connection with the transmitter 110, and the transmitter 110 stores relevant information about these devices. The "All Devices" option includes devices that have established a connection with the transmitter 110 as well as devices that have not established a connection with the transmitter 110.

[0118] As an optional example, if the user selects "sound wave connection" and "all devices" in Figure 6, the transmitter 110 will determine to establish a connection with all devices (devices with locally stored device information and devices without locally stored device information) via sound waves. Furthermore, the transmitter 110 can randomly select a frequency from a preset frequency set as the first frequency. This preset frequency set contains frequencies applicable to a variety of devices, thereby improving the connection success rate.

[0119] As another optional example, if the user selects "acoustic connection" and "local device" in Figure 7, then the transmitter 110 determines to establish a connection with the local device (the device whose device information is stored locally) via acoustic waves. Furthermore, the transmitter 110 can determine a first frequency based on the locally stored device information. For example, the transmitter 110 can query the server 130 for the acoustic communication frequency used by the receiver 120 based on the locally stored device model of the receiver 120. In this way, the transmitter 110 does not need to reselect the frequency, thereby improving the connection speed.

[0120] In the scenario shown in Figure 6, the user can click "Start Connection". Subsequently, the transmitter 110 will execute subsequent steps based on the user's settings and send an acoustic signal, as shown in Figure 8.

[0121] S420, the transmitter 110 determines the second frequency, which is a preset transmission frequency.

[0122] "Preset transmission frequency" refers to the transmission frequency known to both the transmitter 110 and the receiver 120. The second frequency can be configured by the manufacturer, defined by the communication protocol, or determined through negotiation between the transmitter 110 and the receiver 120.

[0123] As an alternative example, the manufacturer or communication protocol defines a preset set of frequencies, which includes at least one frequency for acoustic communication, and the transmitter 110 can determine a frequency from the preset set of frequencies as a second frequency.

[0124] There may be crosstalk between the second frequency and the first frequency. The transmitting end can select a frequency (e.g., the second frequency) from a preset frequency set whose crosstalk level meets the requirements of acoustic communication based on the currently used communication frequency (e.g., the first frequency), so that the second frequency will not cause serious crosstalk to the first frequency, thus flexibly adapting to different communication scenarios.

[0125] For example, if the first frequency is 20000Hz, and the preset frequency set includes two frequencies, namely 19800Hz and 19990Hz, 19990Hz is too close to 20000Hz and may cause serious crosstalk with 20000Hz. In this case, the transmitter 110 can choose 19800Hz as the second frequency.

[0126] After determining the first frequency and the second frequency, the transmitter 110 can perform the following steps.

[0127] S430, the transmitter 110 transmits a first acoustic signal according to a first frequency.

[0128] S440, the transmitter 110 transmits a second acoustic signal according to the second frequency.

[0129] The transmitter 110 can transmit the first acoustic signal and the second acoustic signal based on the method shown in FIG3, or it can transmit the first acoustic signal and the second acoustic signal based on other methods. The embodiments of this application do not limit the specific manner in which the transmitter 110 transmits the first acoustic signal and the second acoustic signal.

[0130] Optionally, the transmitting end 110 may execute S430 and S440 simultaneously, or may not execute S430 and S440 simultaneously. The embodiments of this application do not limit the transmission order of the first acoustic signal and the second acoustic signal.

[0131] For example, the transmitter 110 can modulate the first sound wave signal and the second sound wave signal respectively, and send the first sound wave signal after a certain number of milliseconds after sending the second sound wave signal, or send the second sound wave signal after a certain number of milliseconds after sending the first sound wave signal, or send the first sound wave signal and the second sound wave signal simultaneously.

[0132] Since the relative motion rates of the transmitter 110 and receiver 120 may differ at different times, the Doppler frequency shift may also differ at different times. If the second acoustic signal is transmitted simultaneously with the first acoustic signal, the difference in the Doppler frequency shift between the two acoustic signals can be reduced, thereby improving the accuracy of the correction of the received frequency of the first acoustic signal.

[0133] Optionally, the second acoustic signal carries preset information.

[0134] "Preset information" refers to information known to both the sender 110 and the receiver 120. It can be configured by the manufacturer or determined through negotiation between the sender 110 and the receiver 120. For example, "preset information" can be an identifier of the sender 110 or an identifier that the sender 110 and the receiver 120 negotiated and determined in previous communications.

[0135] Since there may be other acoustic signals in the area where the transmitter 110 and receiver 120 are located, the preset information can help the receiver 120 correctly identify the second acoustic signal, thereby improving the accuracy of the correction of the receiving frequency of the first acoustic signal.

[0136] Figure 9 is a schematic diagram of a first acoustic signal and a second acoustic signal provided in an embodiment of this application. In Figure 9, the horizontal axis represents time in seconds, and the vertical axis represents frequency in Hz.

[0137] For receiver 120, the transmission frequency (i.e., the second frequency) of the second acoustic signal is known, and receiver 120 can receive the second acoustic signal in a frequency band near the second frequency. The transmission frequency (i.e., the first frequency) of the first acoustic signal is determined by transmitter 110 from a preset frequency set or locally stored information. Therefore, the first frequency is a frequency supported by receiver 120, and receiver 120 can receive the first acoustic signal in a frequency band including the first frequency. Optionally, the first acoustic signal may also include a spike to identify the first acoustic signal.

[0138] It should be noted that, in Figure 9, the second acoustic signal is used not only to correct the receiving frequency of one acoustic signal, but optionally, the second acoustic signal can also be used to correct the receiving frequency of multiple acoustic signals. The embodiments of this application do not limit the number of such multiple acoustic signals.

[0139] Since there may be relative movement between the receiver 120 and the transmitter 110, the receiver 120 can execute S450 after receiving the second acoustic signal.

[0140] S450, receiver 120 determines the receiving frequency of the second acoustic signal.

[0141] When the receiver 120 receives the second acoustic signal while moving closer to the transmitter 110, the receiving frequency of the second acoustic signal is greater than the second frequency; when the receiver 120 receives the second acoustic signal while moving away from the transmitter 110, the receiving frequency of the second acoustic signal is less than the second frequency; when the receiver 120 receives the second acoustic signal while stationary relative to the transmitter 110, the receiving frequency of the second acoustic signal is equal to the second frequency.

[0142] S460, the receiver 120 determines the first frequency shift based on the receiving frequency and the second frequency of the second acoustic signal.

[0143] The second frequency is denoted as k_i, and the receiving frequency of the second acoustic signal determined by the receiver 120 is denoted as (k_i). ^ Then (k_i) can be used. ^ The difference between k_i and k_i is used as the first frequency shift.

[0144] For example, if the second frequency is 19800Hz, and the receiving frequency of the second sound wave signal is 19810Hz, then the first frequency shift is 10Hz; if the receiving frequency of the second sound wave signal is 19790Hz, then the first frequency shift is -10Hz; if the receiving frequency of the second sound wave signal is 19800Hz, then the first frequency shift is 0Hz.

[0145] After determining the first frequency shift, receiver 120 can execute S470.

[0146] S470, receiver 120 decodes the first acoustic signal according to the first frequency shift.

[0147] The first frequency shift is the frequency shift caused by the Doppler effect on the second sound wave signal. Decoding the first sound wave signal based on the first frequency shift involves using the second sound wave signal to correct the receiving frequency of the first sound wave signal, and then decoding the first sound wave signal based on the corrected receiving frequency.

[0148] --

[0149] The receiving frequency of the first acoustic signal is denoted as (f_i). ^ Using the first frequency shift correction (f_i) ^ The result obtained is (f_i), which is the corrected frequency of the first sound wave signal and can be used to decode the first sound wave signal.

[0150] For example, if the frequency of the first acoustic signal received by the receiver 120 is 20010Hz, that is, the receiving frequency of the first acoustic signal is 20010Hz, and the first frequency shift is 10Hz, then the receiver 120 can correct the receiving frequency of the first acoustic signal to 20000Hz based on 10Hz, and then decode the first acoustic signal based on 20000Hz; if the first frequency shift is -10Hz, then the receiver 120 can correct the receiving frequency of the first acoustic signal to 20020Hz based on -10Hz, and then decode the first acoustic signal based on 20020Hz.

[0151] Optionally, if the transmitter 110 and receiver 120 are used in a screen mirroring scenario, when the receiver 120 receives the first acoustic signal, it can display the interface shown in Figure 10 and indicate to the user that a screen mirroring connection is currently being established with the transmitter 110 through the content within the dashed box. If the first acoustic signal is successfully decoded, the receiver 120 can obtain the screen mirroring verification information carried by the first acoustic signal and establish a Wi-Fi direct connection with the transmitter 110 based on this verification information. If the Wi-Fi direct connection is successfully established, the receiver 120 can display the interface shown in Figure 11 and indicate to the user that a screen mirroring operation can be performed through the content within the dashed box.

[0152] In summary, the second frequency is a preset transmission frequency. The receiver 120 can determine the transmission frequency of the second acoustic signal. Thus, after receiving the second acoustic signal, the receiver 120 can determine the Doppler frequency shift of the second acoustic signal, i.e., the first frequency shift, based on the receiving and transmission frequencies. Typically, the transmission interval between the first and second acoustic signals is not too long (e.g., the difference between the transmission times of the first and second acoustic signals is less than or equal to a time threshold). The Doppler effects of the first and second acoustic signals are also similar. Therefore, the first frequency shift can be used to correct the receiving frequency of the first acoustic signal, thereby reducing the interference of the Doppler effect on acoustic communication.

[0153] In some cases, the second acoustic signal may be interfered with by other acoustic signals or obstructions, resulting in a large error in the Doppler frequency shift calculated based on the second acoustic signal. The transmitter 110 and receiver 120 can use multiple acoustic signals to correct the receiving frequency of the first acoustic signal.

[0154] Optionally, as shown in Figure 12, method 400 further includes:

[0155] S481, Transmitter 110 determines the third frequency, which is a preset transmission frequency.

[0156] S482, the transmitter 110 transmits a third acoustic signal according to a third frequency, and the third acoustic signal is used to correct the receiving frequency of the first acoustic signal.

[0157] Accordingly, receiver 120 receives the third acoustic signal according to the third frequency.

[0158] S483, receiver 120 determines the receiving frequency of the third acoustic signal.

[0159] S484, receiver 120 determines the second frequency shift based on the receiving frequency of the third acoustic signal and the third frequency.

[0160] S485, receiver 120 decodes the first acoustic signal based on the first frequency shift and the second frequency shift.

[0161] Similar to the second acoustic signal, the transmitter 110 can determine a third frequency from a preset frequency set based on the first frequency, wherein the crosstalk between the third frequency and the first frequency meets the communication requirements. The third acoustic signal can be transmitted simultaneously with the first acoustic signal or separately. The third acoustic signal can also carry preset information to help the receiver 120 correctly identify the third acoustic signal, thereby improving the accuracy of the receiving frequency correction of the first acoustic signal. The specific characteristics of the third acoustic signal can be referred to the relevant description of the second acoustic signal, and will not be repeated here.

[0162] In some cases, the second acoustic signal may be interfered with by other acoustic signals or obstructions, resulting in a large error in the Doppler frequency shift calculated based on the second acoustic signal. In this embodiment, the transmitting end 110 transmits multiple acoustic signals to correct the receiving frequency of the first acoustic signal, and the receiving end 120 uses these multiple acoustic signals to calculate the Doppler frequency shift, which can reduce the calculation error of the Doppler frequency shift.

[0163] The following example, with reference to Figure 13, illustrates the decoding of the first sound wave signal based on the third and second sound wave signals.

[0164] In Figure 13, the horizontal axis represents time in seconds, and the vertical axis represents frequency in Hz. As shown in Figure 13, the transmission frequency (i.e., the third frequency) of the third sound wave signal is 22560Hz, and the receiving frequency of the third sound wave signal determined by the receiver 120 is 22572Hz. Therefore, the receiver 120 can determine the second frequency shift to be 12Hz, and take the average of the first and second frequency shifts. If the first frequency shift is 10Hz, the receiver 120 can determine the final frequency shift to be 11Hz. If the receiving frequency of the first sound wave signal is 20010Hz, the receiver 120 can correct the receiving frequency of the first sound wave signal to 19999Hz based on 11Hz, and then decode the first sound wave signal based on 19999Hz.

[0165] The receiver 120 can also process the first frequency shift and the second frequency shift based on other methods, such as obtaining the final frequency shift based on the weights of the first frequency shift and the second frequency shift. The embodiments of this application do not limit the specific way in which the receiver 120 processes the first frequency shift and the second frequency shift.

[0166] In the example described above, the first acoustic signal is used to transmit data, and the second and third acoustic signals are used to correct the receiving frequency of the first acoustic signal. The acoustic signal used to transmit data can be called a communication signal, and the acoustic signal used to correct the receiving frequency of the communication signal can be called a probe signal.

[0167] In some cases, acoustic signals may be interfered with by other acoustic signals or obstructions, leading to a deterioration in the communication quality of individual acoustic signals. In such situations, the transmitter 110 transmits multiple acoustic signals for communication. This way, even if some acoustic signals are interfered with, the receiver 120 can still communicate using the uninterrupted acoustic signals, thereby improving the reliability of acoustic communication.

[0168] Optionally, as shown in Figure 14, method 400 further includes:

[0169] S491, Transmitter 110 determines the fourth frequency.

[0170] The fourth frequency is the carrier frequency used by the transmitter 110 and receiver 120 for acoustic communication. The fourth frequency can be an ultrasonic frequency, a subsonic ultrasonic frequency (e.g., a frequency in the 16kHz to 20kHz band), or a frequency in other frequency bands supported by the transmitter 110 and receiver 120. This application does not limit the specific value of the fourth frequency.

[0171] The sending end 110 can trigger the execution of S491 based on the process shown in Figures 5 to 7.

[0172] S492, Transmitter 110 determines the fifth frequency, which is the preset transmission frequency.

[0173] Crosstalk may exist between the fifth frequency and other frequencies. The transmitter can select a frequency (e.g., the fifth frequency) from a preset frequency set that meets the requirements of acoustic communication based on the currently used communication frequency (e.g., the first frequency and the fourth frequency). This ensures that the fifth frequency will not cause serious crosstalk to the communication frequency, thus allowing for flexible adaptation to different communication scenarios.

[0174] S493, Transmitter 110 transmits a fourth acoustic signal according to the fourth frequency.

[0175] The fourth acoustic signal can be transmitted simultaneously with the first acoustic signal, or it can be transmitted separately. Optionally, the fourth acoustic signal can carry the same information as the first acoustic signal to improve the success rate of acoustic communication.

[0176] S494, Transmitter 110 transmits a fifth acoustic signal according to a fifth frequency. The fifth acoustic signal is used to correct the receiving frequency of the fourth acoustic signal.

[0177] Accordingly, receiver 120 can perform the following actions: receive the fourth acoustic signal; receive the fifth acoustic signal according to the fifth frequency.

[0178] The transmitter 110 can transmit the fourth and fifth acoustic signals based on the method shown in FIG3, or it can transmit the fourth and fifth acoustic signals based on other methods. The embodiments of this application do not limit the specific manner in which the transmitter 110 transmits the fourth and fifth acoustic signals.

[0179] Optionally, the transmitting end 110 may execute S493 and S494 simultaneously or not simultaneously. The embodiments of this application do not limit the transmission order of the fourth and fifth acoustic signals.

[0180] For example, the transmitter 110 can modulate the fourth sound wave signal and the fifth sound wave signal respectively, and send the first sound wave signal after a certain number of milliseconds after sending the fourth sound wave signal, or send the fourth sound wave signal after a certain number of milliseconds after sending the fifth sound wave signal, or send the fourth sound wave signal and the fifth sound wave signal simultaneously.

[0181] Since the relative motion rates of the transmitter 110 and receiver 120 may differ at different times, the Doppler frequency shift may also differ at different times. If the fourth and fifth acoustic signals are transmitted simultaneously, the difference in the Doppler frequency shift between the two acoustic signals can be reduced, thereby improving the accuracy of the received frequency correction of the fourth acoustic signal.

[0182] Optionally, the fifth acoustic signal carries preset information.

[0183] "Preset information" refers to information known to both the sender 110 and the receiver 120. It can be configured by the manufacturer or determined through negotiation between the sender 110 and the receiver 120. For example, "preset information" can be an identifier of the sender 110 or an identifier that the sender 110 and the receiver 120 negotiated and determined in previous communications.

[0184] Since there may be other acoustic signals in the area where the transmitter 110 and receiver 120 are located, the preset information can help the receiver 120 correctly identify the fifth acoustic signal, thereby improving the accuracy of the correction of the receiving frequency of the fourth acoustic signal.

[0185] Figure 15 is a schematic diagram of the fourth and fifth acoustic signals provided in an embodiment of this application. In Figure 15, the horizontal axis represents time in seconds, and the vertical axis represents frequency in Hz.

[0186] For receiver 120, the transmission frequencies of the second acoustic signal (i.e., the second frequency) and the fifth acoustic signal (i.e., the fifth frequency) are known. Receiver 120 can receive the second acoustic signal in a frequency band near the second frequency and the fifth acoustic signal in a frequency band near the fifth frequency. The transmission frequencies of the first acoustic signal (i.e., the first frequency) and the fourth acoustic signal (i.e., the fourth frequency) are determined by transmitter 110 from a preset frequency set or locally stored information. Therefore, the first frequency and the fourth frequency are frequencies supported by receiver 120. Receiver 120 can receive the first acoustic signal in a frequency band including the first frequency and the fourth acoustic signal in a frequency band including the fourth frequency. Optionally, the first acoustic signal and the fourth acoustic signal each include a spike to identify the first acoustic signal and the fourth acoustic signal.

[0187] Optionally, the difference between the fifth frequency and the fourth frequency is less than the difference between the second frequency and the fourth frequency, and / or the difference between the fifth frequency and the first frequency is greater than the difference between the second frequency and the first frequency.

[0188] The Doppler frequency shift of sound wave signals varies in different frequency bands. Using sound wave signals with similar frequency bands to correct the receiving frequency can improve the accuracy of the receiving frequency correction.

[0189] For example, the first frequency is 20000Hz, the second frequency is 19800Hz, the fourth frequency is 22000Hz, and the fifth frequency is 22560Hz. Here, the first and fourth frequencies are the frequencies of the communication signals, and the second and fifth frequencies are the frequencies of the probe signals. Since the difference between the fifth and fourth frequencies is smaller than the difference between the second and fourth frequencies, and the difference between the fifth and first frequencies is greater than the difference between the second and first frequencies, the transmitting end 110 can simultaneously transmit the first and second acoustic signals, as well as the fourth and fifth acoustic signals. The receiving end 120 can calculate the receiving frequencies of the various communication signals and probe signals received, and use the probe signals to correct the receiving frequencies of communication signals with similar receiving frequencies.

[0190] Optionally, there is a preset association between the fifth frequency and the frequency band where the fourth frequency is located, and / or, there is a preset association between the second frequency and the frequency band where the first frequency is located.

[0191] The frequency bands with close Doppler shift and / or low crosstalk can be determined based on preliminary experimental results or a priori knowledge. For example, if the Doppler shift of the fifth frequency is close to that of the fourth frequency, the correlation between the frequency band where the fifth frequency is located and the frequency band where the fourth frequency is located can be predetermined. If the crosstalk between the second frequency and the first frequency is low, the correlation between the frequency band where the second frequency is located and the frequency band where the first frequency is located can be predetermined.

[0192] For example, the second frequency is 19800Hz and the fifth frequency is 22560Hz. The second frequency can be preset to correct the receiving frequency of communication signals in the 20000-21000Hz band, and the fifth frequency can be preset to correct the receiving frequency of communication signals in the 21000-22000Hz band. In this way, the transmitting end 110 and / or the receiving end 120 can determine the fifth frequency and the second frequency without performing complex calculations, thereby reducing the computational resource overhead of correcting the receiving frequency.

[0193] Since there may be relative movement between the receiver 120 and the transmitter 110, the receiver 120 can execute S495 after receiving the fifth acoustic signal.

[0194] S495, receiver 120 determines the receiving frequency of the fifth acoustic signal.

[0195] When the receiver 120 receives the fifth acoustic signal while moving closer to the transmitter 110, the receiving frequency of the fifth acoustic signal is greater than the fifth frequency; when the receiver 120 receives the fifth acoustic signal while moving away from the transmitter 110, the receiving frequency of the fifth acoustic signal is less than the fifth frequency; when the receiver 120 receives the fifth acoustic signal while stationary relative to the transmitter 110, the receiving frequency of the fifth acoustic signal is equal to the fifth frequency.

[0196] S496, receiver 120 determines the third frequency shift based on the receiving frequency of the fifth acoustic signal and the fifth frequency.

[0197] For example, if the fifth frequency is 22560Hz, and the receiving frequency of the fifth sound wave signal is 22570Hz, then the third frequency shift is 10Hz; if the receiving frequency of the fifth sound wave signal is 22550Hz, then the third frequency shift is -10Hz; if the receiving frequency of the fifth sound wave signal is 22560Hz, then the third frequency shift is 0Hz.

[0198] After determining the third frequency shift, receiver 120 can execute S497.

[0199] S497, receiver 120 decodes the fourth acoustic signal based on the third frequency shift.

[0200] For example, if the frequency of the fourth sound wave signal received by the receiver 120 is 22010Hz, that is, the receiving frequency of the fourth sound wave signal is 22010Hz, and the third frequency shift is 10Hz, then the receiver 120 can correct the receiving frequency of the fourth sound wave signal to 22000Hz based on 10Hz, and then decode the fourth sound wave signal based on 22000Hz; if the third frequency shift is -10Hz, then the receiver 120 can correct the receiving frequency of the fourth sound wave signal to 22020Hz based on -10Hz, and then decode the fourth sound wave signal based on 22020Hz.

[0201] In some cases, due to obstruction or relative movement, even if the receiving frequency is corrected by the probe signal, the communication signal cannot be decoded correctly. In such cases, the transmitter 110 and / or receiver 120 may prompt the user to keep the transmitter 110 and receiver 120 relatively stationary, and / or to keep the transmitter 110 and receiver 120 unobstructed.

[0202] For example, if the transmitter 110 does not receive feedback information about the first sound wave signal after transmitting the first sound wave signal for a period of time, or receives feedback information indicating that the decoding of the first sound wave signal has failed, then the transmitter 110 determines that the reception of the first sound wave signal has failed. The transmitter 110 may output a first message prompting the user to keep the transmitter 110 and the receiver 120 relatively stationary, and / or to keep there no obstruction between the transmitter 110 and the receiver 120.

[0203] The first information may be one or more of text, voice, and other forms of information. The embodiments of this application do not limit the specific form of the first information.

[0204] For example, as shown in Figure 16, when the transmitter 110 determines that the first acoustic signal reception has failed, it prompts the user to clear any obstructions between the transmitter 110 and the receiver 120 and to keep the transmitter 110 and the receiver 120 relatively still by displaying the text "Please ensure there are no obstructions between the devices and keep the devices relatively still." This text is an example of the first information. Optionally, the transmitter 110 can also prompt the user to clear any obstructions between the transmitter 110 and the receiver 120 and to keep the transmitter 110 and the receiver 120 relatively still by playing an audio message; this audio message is also an example of the first information. Optionally, the transmitter 110 can also display text and play audio simultaneously.

[0205] The first information shown in Figure 16 is an example and not a limitation. The first information may also be: other content that prompts the user to keep the sending end 110 and the receiving end 120 relatively stationary, and / or other content that prompts the user to keep the sending end 110 and the receiving end 120 unobstructed. The embodiments of this application do not limit the specific content of the first information.

[0206] After completing the corresponding processing based on the prompts in the first message, the user can click the "Retry" option to trigger the transmitter 110 to re-establish the connection with the receiver 120, thereby improving the success rate of acoustic communication between the transmitter 110 and the receiver 120.

[0207] In addition to the first information output by the transmitter 110, the receiver 120 can also output a fourth information, prompting the user to keep the transmitter 110 and receiver 120 relatively stationary, and / or to keep the transmitter 110 and receiver 120 unobstructed.

[0208] For example, if the receiver 120 fails to decode the first sound wave signal after receiving it, then the receiver 120 determines that the reception of the first sound wave signal has failed. The receiver 120 can output a fourth message, which prompts the user to keep the transmitter 110 and the receiver 120 relatively stationary, and / or to keep there is no obstruction between the transmitter 110 and the receiver 120.

[0209] The fourth information may be one or more of text, voice, and other forms of information. The embodiments of this application do not limit the specific form of the fourth information.

[0210] For example, as shown in Figure 17, when the receiver 120 determines that the first acoustic signal reception has failed, it displays the text "Please ensure there are no obstructions between the devices and keep them relatively still" to prompt the user to clear any obstructions between the transmitter 110 and the receiver 120, and to keep the transmitter 110 and the receiver 120 relatively still. This text is an example of the first information. Optionally, the receiver 120 can also play a voice prompt to prompt the user to clear any obstructions between the transmitter 110 and the receiver 120, and to keep the transmitter 110 and the receiver 120 relatively still; this voice prompt is also an example of the first information. Optionally, the receiver 120 can also display text and play voice simultaneously.

[0211] The fourth information shown in Figure 17 is an example and not a limitation. The fourth information may also be: other content that prompts the user to keep the transmitter 110 and receiver 120 relatively stationary, and / or other content that prompts the user to keep the transmitter 110 and receiver 120 unobstructed. The embodiments of this application do not limit the specific content of the fourth information.

[0212] After the user completes the corresponding processing based on the prompts in the fourth information, the sending end 110 is triggered to re-establish the connection with the receiving end 120, thereby improving the success rate of acoustic communication between the sending end 110 and the receiving end 120.

[0213] Optionally, after the receiver 120 correctly decodes the first acoustic signal, it can send the reception result back to the transmitter 110 via the second information.

[0214] As shown in Figure 18, method 400 further includes:

[0215] S4101, receiver 120 sends second information, indicating that the first acoustic signal was successfully received.

[0216] Accordingly, the sending end 110 receives the second information.

[0217] For example, the receiver 120 can write the receiving frequency of the first acoustic signal in field 1 and write a bit "1" in field 2 to indicate that the frequency indicated by field 1 has been successfully received. After receiving field 1 and field 2, the transmitter 110 determines that the first acoustic signal has been successfully received.

[0218] For example, receiver 120 can write the receiving frequency of the first acoustic signal in field 1 and write a bit "1" in field 2 to indicate that the frequency indicated by field 1 was successfully received; receiver 120 can also write the receiving frequency of the fourth acoustic signal in field 3 and write a bit "0" in field 4 to indicate that the frequency indicated by field 3 was not received. After receiving fields 1, 2, 3, and 4, transmitter 110 determines that the first acoustic signal was successfully received and that the fourth acoustic signal was not received.

[0219] The second information can be transmitted via sound waves or electromagnetic waves. The embodiments of this application do not limit the specific transmission method of the second information.

[0220] S4102, the transmitting end 110 stores the first frequency according to the second information.

[0221] After receiving the second information, the transmitter 110 stores the first frequency. Subsequently, it can directly use the first frequency to communicate with the receiver 120 without trying other frequencies, thus improving the efficiency of subsequent acoustic communication. Optionally, the transmitter 110 can also record information indicating that the receiver 120 cannot use the fourth frequency. If multiple acoustic signals are needed to communicate with the receiver 120 later, frequencies other than the fourth frequency can be tried to improve the success rate of acoustic communication.

[0222] Optionally, method 400 further includes:

[0223] S4103, receiver 120 sends third information to instruct the receiver of the first acoustic signal.

[0224] Accordingly, the sending end 110 receives the third information.

[0225] In some scenarios, the transmitter 110 may communicate with multiple receivers via sound waves. After successfully decoding the first sound wave signal, the receiver of the first sound wave signal can send the third information indicating itself to the transmitter, so that the transmitter can determine the receiver corresponding to the first frequency.

[0226] The third information may be the device model of the receiver 120, or other information that can identify the receiver 120. The embodiments of this application do not limit the specific content of the third information.

[0227] The third information can be transmitted via sound waves or electromagnetic waves. The embodiments of this application do not limit the specific transmission method of the third information.

[0228] The third information can be transmitted simultaneously with the second information, or it can be transmitted separately from the second information.

[0229] S4104, the transmitting end 110 stores the information of the receiving end 120 according to the third information.

[0230] The third piece of information can be the same as or different from the information received by the receiver.

[0231] For example, the third piece of information is the device model of the receiving end 120, and the sending end 110 can directly store the device model as information of the receiving end 120 locally.

[0232] For example, the third piece of information is the media access control (MAC) address of the receiving end 120. The sending end 110 can determine the device model of the receiving end 120 based on the MAC address and store the device model as information of the receiving end 120 locally.

[0233] Optionally, in method 400, after the transmitting end 110 determines that the first acoustic signal has been successfully received, it can send the device information of the receiving end 120 and the first frequency to the server 130.

[0234] Optionally, in method 400, after the receiving end 120 successfully receives the first acoustic signal, it can align the transmission frequency of the first acoustic signal with the transmitting end 110. For example, the receiving end 120 can obtain the first frequency from the transmitting end 110 through a Wi-Fi direct connection, and then send the device information of the receiving end 120 and the first frequency to the server 130.

[0235] When other devices need to communicate with receiver 120 via sound waves, they can query server 130 for the sound wave communication frequency used by receiver 120 based on the device information of receiver 120, such as the first frequency. The first frequency is a verified frequency that can be used directly, and other devices do not need to try other frequencies, thereby improving the efficiency of sound wave communication.

[0236] Below are some specific examples based on method 400, where television (TV) is an example of the transmitter 110 and mobile phone is an example of the receiver 120.

[0237] Since most smart devices currently support audio playback and acquisition frequencies up to 44100Hz, subsonic and certain frequency bands of ultrasound can be used to replace screen-sharing codes for communication between devices within the conference room. Furthermore, subsonic (around 20kHz) sound waves lack wall-penetrating properties. In a conference setting, devices outside the conference room cannot receive the ultrasonic verification signal played by the screen-sharing device inside and therefore cannot access the conference content. Thus, subsonic short-range communication offers greater security compared to traditional screen-sharing code input.

[0238] As shown in Figure 19, Example 1900 includes:

[0239] S1901, TV detects whether the mobile phone is a known device.

[0240] For example, as shown in Figure 7, after the user selects "Local Devices," the TV can display devices that have previously been cast to the TV. It should be noted that these devices may have undergone casting verification via acoustic connection or other methods. Therefore, after the user selects a mobile phone as the connection target, the TV also needs to detect whether the phone is a known device, that is, to determine whether the phone has previously communicated with the TV via acoustic waves.

[0241] If the TV cannot find the acoustic frequency band used by the mobile phone, the TV can execute S1902; if the TV finds the acoustic frequency band used by the mobile phone, the TV can execute S1903.

[0242] S1902, TV transmits multi-band communication signals and a single probe signal.

[0243] For example, if the mobile phone has never communicated with the TV via acoustic waves, the TV is unsure of the acoustic frequency bands supported by the mobile phone, or the TV cannot find the supported acoustic frequency bands, the TV can send multi-frequency communication signals to improve the success rate of acoustic communication. These multi-frequency bands could be, for example, 20–21 kHz and 21–22 kHz, and the frequency of the single probe signal could be, for example, 22560 Hz.

[0244] S1903, TV transmits communication signals in the target frequency band and a single probe signal.

[0245] For example, if a mobile phone has communicated with a TV using sound waves, the TV will store the sound wave frequency bands used by the phone, i.e., the target frequency band (one or more frequency bands). Alternatively, even if the mobile phone has not communicated with the TV using sound waves, the TV can query the server to find the sound wave frequency bands supported by the phone. In this case, the TV can directly send communication signals of the target frequency band, thereby improving the efficiency of sound wave communication.

[0246] S1904: After filtering the received audio signal, the mobile phone uses the FFT algorithm to decode the audio signal.

[0247] The mobile phone can first try to decode all received audio signals (including the aforementioned communication signals and probe signals). If the relative movement speed between the mobile phone and the TV is small, the audio signal is less affected by the Doppler effect, and the mobile phone may directly decode the information carried by the communication signal. Then, the mobile phone can perform subsequent screen casting connection steps based on the information carried by the communication signal, such as sending mobile phone information for screen casting verification to the TV.

[0248] If the relative speed of movement between the mobile phone and the TV is high, the audio signal will be greatly affected by the Doppler effect, and the mobile phone may not be able to decode the information carried by the communication signal. In this case, the mobile phone can first decode the probe signal and buffer the communication signal.

[0249] S1905, the mobile phone calculates the Doppler frequency shift based on the known frequency of the probe signal and the frequency of the decoded probe signal, corrects the receiving frequency of the communication signal based on the Doppler frequency shift, and decodes the communication signal based on the corrected receiving frequency.

[0250] For example, the probe signal mentioned above is probe signal A, and the transmission frequency f of probe signal A is... A1 This is information known to the mobile phone: the receiving frequency f of probe signal A. A2 This information is measured by the mobile phone, and the mobile phone can use it based on f A1 and f A2 Once the frequency shift A is obtained, the mobile phone can then correct the receiving frequency of each communication signal based on the frequency shift A.

[0251] If the communication signal is successfully decoded, subsequent screen mirroring connection steps are executed based on the information carried by the communication signal, such as sending mobile phone information for screen mirroring verification to the TV. If the communication signal still fails to decode, the mobile phone can prompt the user to keep the mobile phone and TV relatively stationary and to ensure that there are no obstructions between the mobile phone and TV.

[0252] After the communication signal is successfully decoded, the mobile phone can execute S1906.

[0253] S1906, the mobile phone records the target frequency band (the frequency band where the successfully decoded communication signal is located) and sends the target frequency band and the mobile phone's device information to the TV.

[0254] Mobile phones can send target frequency bands and device information to TVs via sound waves, or they can send target frequency bands and device information to TVs via other means.

[0255] S1907, TV stores target frequency band and mobile device information.

[0256] The TV stores the target frequency band and the phone's device information locally for future use in acoustic communication with the phone. The TV can also send the target frequency band and phone's device information to a server for use by other devices when communicating with the phone via acoustic waves.

[0257] S1908, TV determines whether the mobile phone information has passed verification.

[0258] For example, a TV can send a screen mirroring code to a mobile phone via a communication signal. The mobile phone then decodes the communication signal to obtain the screen mirroring code, which it then sends back to the TV as mobile phone information for verification. If the screen mirroring code received by the TV is the same as the one sent by the TV, the TV determines that the mobile phone information verification has passed and executes step S1910; if the screen mirroring code received by the TV is different from the one sent by the TV, the TV determines that the mobile phone information verification has failed and executes step S1909. The mobile phone can also send other information (such as mobile phone user information) to the TV for verification, so that the TV can determine whether the mobile phone user has permission to mirror the screen.

[0259] S1909, TV rejects mobile phone screen mirroring.

[0260] S1910, TV allows screen mirroring from mobile phones.

[0261] Table 1 shows the test results for Example 1900.

[0262] Table 1

[0263] Table 1 shows four test environments. "5 meters" refers to the initial vertical distance between the mobile phone and the TV screen being 5 meters. "90 degrees" refers to the angle between the normal of the mobile phone and the TV screen being 90 degrees. "45 degrees" refers to the angle between the normal of the mobile phone and the TV screen being 45 degrees. "From near to far" and "from far to near" refer to the direction of relative movement between the mobile phone and the TV.

[0264] Other conditions of the test environment include: a 6m*8m conference room, a single probe signal (22560Hz), and a waiting time of 2 seconds for each connection.

[0265] Without applying method 400, 100 connection tests were performed in four test environments, with 18, 9, 12, and 0 successful connections, respectively. During testing of Example 1900, 100 connection tests were performed in the same four test environments, with 24, 70, 91, and 77 successful connections, respectively.

[0266] As shown in Table 1, compared to the case where method 400 was not applied, the connection success rate of Example 1900 was significantly improved in all test environments.

[0267] As shown in Figure 20, Example 2000 includes:

[0268] S2001, TV detects whether the mobile phone is a known device.

[0269] For example, as shown in Figure 7, after the user selects "Local Devices," the TV can display devices that have previously been cast to the TV. It should be noted that these devices may have undergone casting verification via acoustic connection or other methods. Therefore, after the user selects a mobile phone as the connection target, the TV also needs to detect whether the phone is a known device, that is, to determine whether the phone has previously communicated with the TV via acoustic waves.

[0270] If the TV cannot find the acoustic frequency band used by the mobile phone, the TV can execute S2002; if the TV finds the acoustic frequency band used by the mobile phone, the TV can execute S2003.

[0271] S2002, TV transmits multi-band communication signals and two probe signals.

[0272] For example, if the mobile phone has never communicated with the TV using acoustic waves, the TV is unsure of the acoustic frequency bands supported by the mobile phone, or the TV cannot find any supported acoustic frequency bands, the TV can send multi-frequency communication signals to improve the success rate of acoustic communication. These multi-frequency bands could be, for example, 20–21 kHz and 21–22 kHz, and the frequencies of the two probe signals could be, for example, 19800 Hz and 22560 Hz.

[0273] S2003, TV transmits communication signals for the target frequency band and two probe signals.

[0274] For example, if a mobile phone has communicated with a TV using sound waves, the TV will store the sound wave frequency bands used by the phone, i.e., the target frequency band (one or more frequency bands). Alternatively, even if the mobile phone has not communicated with the TV using sound waves, the TV can query the server to find the sound wave frequency bands supported by the phone. In this case, the TV can directly send communication signals of the target frequency band, thereby improving the efficiency of sound wave communication.

[0275] S2004: After filtering the received audio signal, the mobile phone uses the FFT algorithm to decode the audio signal.

[0276] The mobile phone can first try to decode all received audio signals (including the aforementioned communication signals and probe signals). If the relative movement speed between the mobile phone and the TV is small, the audio signal is less affected by the Doppler effect, and the mobile phone may directly decode the information carried by the communication signal. Then, the mobile phone can perform subsequent screen casting connection steps based on the information carried by the communication signal, such as sending mobile phone information for screen casting verification to the TV.

[0277] If the relative speed of movement between the mobile phone and the TV is high, the audio signal will be greatly affected by the Doppler effect, and the mobile phone may not be able to decode the information carried by the communication signal. In this case, the mobile phone can first decode the probe signal and buffer the communication signal.

[0278] S2005: The mobile phone calculates two Doppler frequency shifts based on the frequencies of two known probe signals and the frequencies of two decoded probe signals. It then corrects the receiving frequency of the communication signal based on the two Doppler frequency shifts and decodes the communication signal based on the corrected receiving frequency.

[0279] For example, the two probe signals mentioned above are probe signal A and probe signal B, and the transmission frequency f of probe signal A is... A1 This is information known to the mobile phone: the receiving frequency f of probe signal A. A2 This information is measured by the mobile phone, and the mobile phone can use it based on f A1 and f A2 The frequency shift A is obtained; the transmission frequency f of the probe signal B is also obtained. B1 This is information known to the mobile phone: the receiving frequency f of probe signal B. B2 This information is measured by the mobile phone, and the mobile phone can use it based on f B1 and f B2 The frequency shift B is obtained; subsequently, the mobile phone can calculate the average value of frequency shift A and frequency shift B, and correct the receiving frequency of each communication signal based on this average value.

[0280] If the communication signal is successfully decoded, subsequent screen mirroring connection steps are executed based on the information carried by the communication signal, such as sending mobile phone information for screen mirroring verification to the TV. If the communication signal still fails to decode, the mobile phone can prompt the user to keep the mobile phone and TV relatively stationary and to ensure that there are no obstructions between the mobile phone and TV.

[0281] After the communication signal is successfully decoded, the mobile phone can execute S2006.

[0282] S2006, the mobile phone records the target frequency band (the frequency band where the successfully decoded communication signal is located) and sends the target frequency band and the mobile phone's device information to the TV.

[0283] Mobile phones can send target frequency bands and device information to TVs via sound waves, or they can send target frequency bands and device information to TVs via other means.

[0284] S2007, TV stores target frequency band and mobile phone device information.

[0285] The TV stores the target frequency band and the phone's device information locally for future use in acoustic communication with the phone. The TV can also send the target frequency band and phone's device information to a server for use by other devices when communicating with the phone via acoustic waves.

[0286] S2008, TV determines whether the mobile phone information has passed verification.

[0287] For example, a TV can send a screen mirroring code to a mobile phone via a communication signal. The mobile phone then decodes the communication signal to obtain the screen mirroring code, which is then sent back to the TV as mobile phone information for verification. If the screen mirroring code received by the TV is the same as the one sent by the TV, the TV determines that the mobile phone information verification has passed and executes S2010; if the screen mirroring code received by the TV is different from the one sent by the TV, the TV determines that the mobile phone information verification has failed and executes S2009. The mobile phone can also send other information (such as mobile phone user information) to the TV for verification, so that the TV can determine whether the mobile phone user has permission to mirror the screen.

[0288] S2009, TV rejects mobile phone screen mirroring.

[0289] S2010, TV allows screen mirroring from mobile phones.

[0290] As shown in Figure 21, Example 2100 includes:

[0291] S2101, TV detects whether the mobile phone is a known device.

[0292] For example, as shown in Figure 7, after the user selects "Local Devices," the TV can display devices that have previously been cast to the TV. It should be noted that these devices may have undergone casting verification via acoustic connection or other methods. Therefore, after the user selects a mobile phone as the connection target, the TV also needs to detect whether the phone is a known device, that is, to determine whether the phone has previously communicated with the TV via acoustic waves.

[0293] If the TV cannot find the acoustic frequency band used by the mobile phone, the TV can execute S2102; if the TV finds the acoustic frequency band used by the mobile phone, the TV can execute S2103.

[0294] S2102, TV transmits multi-band communication signals and two probe signals.

[0295] For example, if the mobile phone has never communicated with the TV using acoustic waves, the TV is unsure of the acoustic frequency bands supported by the mobile phone, or the TV cannot find any supported acoustic frequency bands, the TV can send multi-frequency communication signals to improve the success rate of acoustic communication. These multi-frequency bands could be, for example, 20–21 kHz and 21–22 kHz, and the frequencies of the two probe signals could be, for example, 19800 Hz and 22560 Hz.

[0296] S2103, TV transmits communication signals in the target frequency band and two probe signals.

[0297] For example, if a mobile phone has communicated with a TV using sound waves, the TV will store the sound wave frequency bands used by the phone, i.e., the target frequency band (one or more frequency bands). Alternatively, even if the mobile phone has not communicated with the TV using sound waves, the TV can query the server to find the sound wave frequency bands supported by the phone. In this case, the TV can directly send communication signals of the target frequency band, thereby improving the efficiency of sound wave communication.

[0298] S2104: After filtering the received audio signal, the mobile phone decodes the audio signal using the FFT algorithm.

[0299] The mobile phone can first try to decode all received audio signals (including the aforementioned communication signals and probe signals). If the relative movement speed between the mobile phone and the TV is small, the audio signal is less affected by the Doppler effect, and the mobile phone may directly decode the information carried by the communication signal. Then, the mobile phone can perform subsequent screen casting connection steps based on the information carried by the communication signal, such as sending mobile phone information for screen casting verification to the TV.

[0300] If the relative speed of movement between the mobile phone and the TV is high, the audio signal will be greatly affected by the Doppler effect, and the mobile phone may not be able to decode the information carried by the communication signal. In this case, the mobile phone can first decode the probe signal and buffer the communication signal.

[0301] S2105: The mobile phone calculates two Doppler frequency shifts based on the frequencies of two known probe signals and the frequencies of two decoded probe signals. It uses the Doppler frequency shift corresponding to 19800Hz to correct the receiving frequency of the communication signal in the range of 20-21kHz, and uses the Doppler frequency shift corresponding to 22560Hz to correct the receiving frequency of the communication signal in the range of 21-22kHz.

[0302] For example, the two probe signals mentioned above are probe signal A (19800Hz) and probe signal B (22560Hz), respectively. The transmission frequency f of probe signal A is... A1 This is information known to the mobile phone: the receiving frequency f of probe signal A. A2 This information is measured by the mobile phone, and the mobile phone can use it based on f A1 and f A2 The frequency shift A is obtained; the transmission frequency f of the probe signal B is also obtained. B1 This is information known to the mobile phone: the receiving frequency f of probe signal B. B2 This information is measured by the mobile phone, and the mobile phone can use it based on f B1 and f B2 Frequency shift B is obtained; subsequently, the mobile phone can use frequency shift A to correct the receiving frequency of the communication signal in the range of 20-21 kHz, and use frequency shift B to correct the receiving frequency of the communication signal in the range of 21-22 kHz.

[0303] If the communication signal is successfully decoded, subsequent screen mirroring connection steps are executed based on the information carried by the communication signal, such as sending mobile phone information for screen mirroring verification to the TV. If the communication signal still fails to decode, the mobile phone can prompt the user to keep the mobile phone and TV relatively stationary and to ensure that there are no obstructions between the mobile phone and TV.

[0304] After the communication signal is successfully decoded, the mobile phone can execute S2106.

[0305] S2106, the mobile phone records the target frequency band (the frequency band where the successfully decoded communication signal is located) and sends the target frequency band and the mobile phone's device information to the TV.

[0306] Mobile phones can send target frequency bands and device information to TVs via sound waves, or they can send target frequency bands and device information to TVs via other means.

[0307] S2107, TV stores target frequency band and mobile device information.

[0308] The TV stores the target frequency band and the phone's device information locally for future use in acoustic communication with the phone. The TV can also send the target frequency band and phone's device information to a server for use by other devices when communicating with the phone via acoustic waves.

[0309] S2108, TV determines whether the mobile phone information has passed verification.

[0310] For example, the TV can send a screen mirroring code to the mobile phone via a communication signal. The mobile phone then decodes the communication signal to obtain the screen mirroring code, which is then sent back to the TV as mobile phone information for verification. If the screen mirroring code received by the TV is the same as the one sent by the TV, the TV determines that the mobile phone information verification has passed and executes step S2110; if the screen mirroring code received by the TV is different from the one sent by the TV, the TV determines that the mobile phone information verification has failed and executes step S2109. The mobile phone can also send other information (such as mobile phone user information) to the TV for verification, so that the TV can determine whether the mobile phone user has permission to perform screen mirroring.

[0311] S2109, TV rejects mobile phone screen mirroring.

[0312] S2110, TV allows screen mirroring from mobile phones.

[0313] Table 2 shows the test results for Example 2100.

[0314] Table 2

[0315] Table 2 shows two test environments. "3 meters" refers to the initial vertical distance between the mobile phone and the TV screen being 3 meters. "90 degrees" refers to the angle between the normals of the mobile phone and the TV screen being 90 degrees. "From near to far" and "from far to near" refer to the directions of relative motion between the mobile phone and the TV.

[0316] Other conditions of the test environment included: a 4m*5m conference room, two probe signals (19800Hz and 22560Hz), and a waiting time of 2 seconds for each connection.

[0317] Without applying method 400, 100 connection tests were performed in two test environments, with 0 and 8 successful connections respectively. During the testing of Example 2100, 100 connection tests were performed in the same two test environments, with 15 and 35 successful connections respectively.

[0318] As shown in Table 2, compared to the case where method 400 was not applied, the connection success rate of Example 2100 was significantly improved in all test environments.

[0319] The foregoing has detailed the method examples provided by the embodiments of this application. It is understood that the corresponding apparatus, in order to achieve the above functions, includes hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, based on the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0320] Figures 22 and 23 are schematic diagrams of two devices provided in the embodiments of this application. These devices can be used to implement the functions of the transmitting end or the receiving end in the above method embodiments, and therefore also have the beneficial effects of the above method embodiments. In the embodiments of this application, these devices can be the transmitting end 110 or the receiving end 120, or they can be modules (e.g., chips) applied to the transmitting end 110 or the receiving end 120.

[0321] As shown in Figure 22, the device 2200 includes a processing unit 2210 and a transceiver unit 2220. Under the control of the processing unit 2210, the transceiver unit 2220 performs receiving and / or sending steps. When performing the sending step, the transceiver unit 2220 acts as a sending unit, and when performing the receiving step, it acts as a receiving unit. The device 2200 is used to implement the functions of the sending end or the receiving end in the above method embodiments.

[0322] When device 2200 is used to implement the function of transmitter 110 in the embodiment of the method described in FIG4, processing unit 2210 is used to: determine a first frequency; determine a second frequency, the second frequency being a preset transmission frequency; transceiver unit 2220 is used to: transmit a first acoustic signal according to the first frequency; transmit a second acoustic signal according to the second frequency, the second acoustic signal being used to correct the receiving frequency of the first acoustic signal.

[0323] Optionally, the processing unit 2210 is specifically used to: determine a second frequency from a preset frequency set according to a first frequency, wherein the degree of crosstalk between the second frequency and the first frequency meets the communication requirements.

[0324] Optionally, the second acoustic signal is sent simultaneously with the first acoustic signal.

[0325] Optionally, the second acoustic signal carries preset information.

[0326] Optionally, the processing unit 2210 is further configured to: determine a third frequency, wherein the third frequency is a preset transmission frequency; the transceiver unit 2220 is further configured to: transmit a third acoustic signal according to the third frequency, wherein the third acoustic signal is used to correct the reception frequency of the first acoustic signal.

[0327] Optionally, the processing unit 2210 is further configured to: determine a fourth frequency; determine a fifth frequency, wherein the fifth frequency is a preset transmission frequency; the transceiver unit 2220 is further configured to: transmit a fourth acoustic signal according to the fourth frequency; transmit a fifth acoustic signal according to the fifth frequency, wherein the fifth acoustic signal is used to correct the receiving frequency of the fourth acoustic signal.

[0328] Optionally, the difference between the fifth frequency and the fourth frequency is less than the difference between the second frequency and the fourth frequency, and / or the difference between the fifth frequency and the first frequency is greater than the difference between the second frequency and the first frequency.

[0329] Optionally, there is a preset association between the fifth frequency and the frequency band where the fourth frequency is located, and / or, there is a preset association between the second frequency and the frequency band where the first frequency is located.

[0330] Optionally, the transceiver unit 2220 is further configured to: when the first acoustic signal fails to be received, output first information, the first information prompting the user to keep the transmitting end and receiving end of the first acoustic signal relatively stationary, and / or, the first information prompting the user to keep the transmitting end and receiving end of the first acoustic signal unobstructed.

[0331] Optionally, the transceiver unit 2220 is further configured to: receive second information, the second information indicating that the first acoustic signal was successfully received; the processing unit 2210 is further configured to: store the first frequency according to the second information.

[0332] Optionally, the transceiver unit 2220 is further configured to: receive third information, the third information indicating the receiving end of the first acoustic signal; the processing unit 2210 is further configured to: store the information of the receiving end according to the third information.

[0333] Optionally, the transceiver unit 2220 is also used to: send the receiving end's device information and first frequency to the server.

[0334] When device 2200 is used to implement the function of receiver 120 in the embodiment of the method described in FIG4, transceiver unit 2220 is used to: receive a first acoustic signal; receive a second acoustic signal according to a second frequency, the second frequency being a preset transmission frequency; processing unit 2210 is used to: determine the receiving frequency of the second acoustic signal; determine a first frequency shift according to the receiving frequency of the second acoustic signal and the second frequency; and decode the first acoustic signal according to the first frequency shift.

[0335] Optionally, the second acoustic signal and the first acoustic signal are received simultaneously.

[0336] Optionally, the second acoustic signal carries preset information.

[0337] Optionally, the transceiver unit 2220 is further configured to: receive a third acoustic signal according to a third frequency, wherein the third frequency is a preset transmission frequency; the processing unit 2210 is further configured to: determine the receiving frequency of the third acoustic signal; and determine a second frequency shift according to the receiving frequency of the third acoustic signal and the third frequency; wherein the processing unit 2210 is specifically configured to: decode the first acoustic signal according to the first frequency shift and the second frequency shift.

[0338] Optionally, the transceiver unit 2220 is further configured to: receive a fourth acoustic signal; receive a fifth acoustic signal according to a fifth frequency, wherein the fifth frequency is a preset transmission frequency; the processing unit 2210 is further configured to: determine the receiving frequency of the fifth acoustic signal; determine a third frequency shift according to the receiving frequency of the fifth acoustic signal and the fifth frequency; and decode the fourth acoustic signal according to the third frequency shift.

[0339] Optionally, the transceiver unit 2220 is further configured to: when the first acoustic signal fails to be received, output a fourth message, the fourth message prompting the user to keep the transmitting end and receiving end of the first acoustic signal relatively stationary, and / or, the fourth message prompting the user to keep the transmitting end and receiving end of the first acoustic signal unobstructed.

[0340] Optionally, the transceiver unit 2220 is further configured to: when the first acoustic signal is successfully received, send a second message indicating that the first acoustic signal has been successfully received.

[0341] Optionally, the transceiver unit 2220 is also configured to: transmit third information, the third information indicating the receiving end of the first acoustic signal.

[0342] Optionally, the transceiver unit 2220 is further configured to: obtain a first frequency from the transmitting end of the first acoustic signal; and send the receiving end's device information and the first frequency to the server.

[0343] The processing unit 2210 can be implemented in hardware or software. When implemented in hardware, the processing unit 2210 can be a logic circuit, integrated circuit, etc. When implemented in software, the processing unit 2210 can be a general-purpose processor that reads software code stored in a storage unit. This storage unit can be integrated into the processing unit 2210 or located outside the processing unit 2210 and exist independently.

[0344] As shown in Figure 23, device 2300 includes a processor 2310 and an interface circuit 2320. The processor 2310 and the interface circuit 2320 are coupled to each other. It is understood that the interface circuit 2320 can be a transceiver or an input / output interface. Optionally, device 2300 may also include a memory 2330 for storing instructions executed by the processor 2310, or storing input data required by the processor 2310 to execute instructions, or storing data generated after the processor 2310 executes instructions.

[0345] When the device 2300 is used to implement the method shown in FIG4, the processor 2310 is used to implement the function of the processing unit 2210, and the interface circuit 2320 is used to implement the function of the transceiver unit 2220.

[0346] When device 2300 is a transmitting chip (i.e., a chip applied to the transmitting end), the transmitting chip implements the functions of the transmitting end in the above method embodiments. The transmitting chip receives information from the receiving end, which can be understood as the information being first received by other modules in the transmitting end (e.g., a microphone), and then sent to the transmitting chip by these modules. The transmitting chip sends information to the receiving end, which can be understood as the information being first sent to other modules in the transmitting end (e.g., a speaker), and then sent to the receiving end by these modules.

[0347] When device 2300 is a receiver chip (i.e., a chip applied to a receiver), the receiver chip implements the functions of the receiver in the above method embodiments. The receiver chip receives information from the transmitter, which can be understood as the information being first received by other modules in the receiver (e.g., a microphone), and then sent to the receiver chip by these modules. The receiver chip sends information to the transmitter, which can be understood as the information being first sent to other modules in the receiver (e.g., a speaker), and then sent to the transmitter by these modules.

[0348] In this application, entity A sends information to entity B, either directly or indirectly through other entities. Similarly, entity B receives information from entity A, either directly or indirectly through other entities. Entities A and B can be electronic devices or modules within electronic devices.

[0349] It is understood that the processor in the embodiments of this application can be a CPU, or other general-purpose processors, digital signal processors (DSPs), ASICs, FPGAs, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. A general-purpose processor can be a microprocessor or any conventional processor.

[0350] The method steps in the embodiments of this application can be implemented in hardware or in software instructions executable by a processor. The software instructions can consist of corresponding software modules, which can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disks, portable hard disks, compact disc read-only memory (CD-ROM), or any other form of storage medium well known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. The storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Alternatively, the ASIC can reside in a base station or terminal. The processor and storage medium can also exist as discrete components in the base station or terminal.

[0351] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this application are performed entirely or partially. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user equipment, or other programmable device. The computer program or instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center integrating one or more available media. The available medium can be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; it can also be an optical medium, such as a digital video optical disc; or it can be a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or non-volatile storage medium, or may include both types of storage media.

[0352] Finally, the following points should be noted regarding the embodiments of this application:

[0353] First, in the embodiments of this application, the terms "first," "second," and various numerical designations are merely for descriptive convenience and are not intended to limit the scope of the embodiments of this application. For example, "first frequency" and "second frequency" represent two frequencies, and there are no other limitations.

[0354] Second, in the embodiments of this application, "instruction" can include direct and indirect instructions, as well as explicit and implicit instructions. The information indicated by a certain piece of information is called the information to be instructed. In specific implementations, there are many ways to instruct the information to be instructed. For example, the information to be instructed can be directly instructed, such as the information to be instructed itself or its index. The information to be instructed can also be indirectly indicated by instructing other information, where there is a correlation between the other information and the information to be instructed. Alternatively, only a part of the information to be instructed can be indicated, while the other parts are known or pre-agreed upon. For example, the indication of the information to be indicated can be achieved by pre-agreed upon (e.g., by a protocol specifying the existence of a certain information element), thereby reducing the instruction overhead to some extent.

[0355] Third, "predefined" or "preconfigured" can be achieved by pre-saving the corresponding code, table, or other information indicative material in the device. This application does not limit the specific implementation method. "Saving" can refer to storing in one or more memories, which can be separate settings or integrated into the processor or communication device; the one or more memories can also be partially separate settings and partially integrated into the processor or device (e.g., the transmitting end or receiving end). The type of memory can be any form of storage medium, and this application does not limit this.

[0356] Fourth, "at least one" means one or more, while "more than" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, or A and B exist simultaneously. Here, A and B can be a single object or multiple objects. The character " / " generally indicates that the preceding and following related objects have an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, and c can mean: a, or, b, or, c, or, a and b, or, a and c, or, b and c, or, a, b, and c. Here, a, b, and c can each be a single object or multiple objects.

[0357] Fifth, in the embodiments of this application, descriptions such as "when," "in the case of," "if," and "if" all refer to the fact that the device (e.g., the sending end or the receiving end) will make corresponding processing under certain objective circumstances. They are not time limits, nor do they require the device to make a judgment action when implementing it, nor do they mean that there are other limitations.

[0358] Sixth, in the various embodiments of this application, unless otherwise specified or logically conflicting, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

Claims

1. A method for transmitting acoustic signals, characterized in that, include: Determine the first frequency; Determine a second frequency, which is a preset transmission frequency; A first acoustic signal is transmitted according to the first frequency; A second acoustic signal is transmitted according to the second frequency, and the second acoustic signal is used to correct the receiving frequency of the first acoustic signal.

2. The method according to claim 1, characterized in that, Determining the second frequency includes: The second frequency is determined from a preset frequency set based on the first frequency, wherein the degree of crosstalk between the second frequency and the first frequency meets the communication requirements.

3. The method according to claim 1 or 2, characterized in that, The second acoustic signal is sent simultaneously with the first acoustic signal.

4. The method according to any one of claims 1 to 3, characterized in that, The second acoustic signal carries preset information.

5. The method according to any one of claims 1 to 4, characterized in that, The method further includes: A third frequency is determined, wherein the third frequency is a preset transmission frequency; A third acoustic signal is transmitted according to the third frequency, and the third acoustic signal is used to correct the receiving frequency of the first acoustic signal.

6. The method according to any one of claims 1 to 5, characterized in that, The method further includes: Determine the fourth frequency; Determine the fifth frequency, which is a preset transmission frequency; A fourth acoustic signal is transmitted according to the fourth frequency; A fifth acoustic signal is transmitted according to the fifth frequency, and the fifth acoustic signal is used to correct the receiving frequency of the fourth acoustic signal.

7. The method according to claim 6, characterized in that, The difference between the fifth frequency and the fourth frequency is less than the difference between the second frequency and the fourth frequency, and / or the difference between the fifth frequency and the first frequency is greater than the difference between the second frequency and the first frequency.

8. The method according to claim 6, characterized in that, There is a preset association between the fifth frequency and the frequency band in which the fourth frequency is located, and / or, there is a preset association between the second frequency and the frequency band in which the first frequency is located.

9. The method according to any one of claims 1 to 8, characterized in that, The method further includes: When the first acoustic signal fails to be received, a first message is output, prompting the user to keep the transmitting and receiving ends of the first acoustic signal relatively stationary, and / or, prompting the user to keep the transmitting and receiving ends of the first acoustic signal unobstructed.

10. The method according to any one of claims 1 to 9, characterized in that, The method further includes: Receive the second information, which indicates that the first acoustic signal was successfully received; The first frequency is stored according to the second information.

11. The method according to claim 10, characterized in that, The method further includes: Receive third information, wherein the third information indicates the receiving end of the first acoustic signal; The device information of the receiving end is stored according to the third information.

12. The method according to claim 11, characterized in that, The method further includes: The device information of the receiving end and the first frequency are sent to the server.

13. A method for decoding acoustic signals, characterized in that, include: Receive the first acoustic signal; The second sound wave signal is received according to the second frequency, which is a preset transmission frequency; Determine the receiving frequency of the second acoustic signal; The first frequency shift is determined based on the receiving frequency of the second acoustic signal and the second frequency; The first acoustic signal is decoded based on the first frequency shift.

14. The method according to claim 13, characterized in that, The second acoustic signal is received simultaneously with the first acoustic signal.

15. The method according to claim 13 or 14, characterized in that, The second acoustic signal carries preset information.

16. The method according to any one of claims 13 to 15, characterized in that, The method further includes: A third acoustic signal is received according to a third frequency, wherein the third frequency is a preset transmission frequency; Determine the receiving frequency of the third acoustic signal; The second frequency shift is determined based on the receiving frequency of the third acoustic signal and the third frequency; Decoding the first acoustic signal based on the first frequency shift includes: The first acoustic signal is decoded based on the first frequency shift and the second frequency shift.

17. The method according to any one of claims 13 to 16, characterized in that, The method further includes: Receives the fourth acoustic signal; The fifth sound wave signal is received according to the fifth frequency, which is a preset transmission frequency; Determine the receiving frequency of the fifth acoustic signal; The third frequency shift is determined based on the receiving frequency of the fifth acoustic signal and the fifth frequency; The fourth acoustic signal is decoded based on the third frequency shift.

18. The method according to any one of claims 13 to 17, characterized in that, The method further includes: When the first acoustic signal fails to be received, a fourth message is output, which prompts the user to keep the transmitting and receiving ends of the first acoustic signal relatively stationary, and / or the fourth message prompts the user to keep the transmitting and receiving ends of the first acoustic signal unobstructed.

19. The method according to any one of claims 13 to 18, characterized in that, The method further includes: When the first acoustic signal is successfully received, a second message is sent, indicating that the first acoustic signal has been successfully received.

20. The method according to claim 19, characterized in that, The method further includes: Send a third message, which instructs the receiving end of the first acoustic signal.

21. The method according to claim 20, characterized in that, The method further includes: The first frequency is obtained from the transmitting end of the first acoustic signal; The device information of the receiving end and the first frequency are sent to the server.

22. A device for transmitting acoustic wave signals, characterized in that, include: A module for performing the method as described in any one of claims 1 to 12.

23. A device for decoding acoustic signals, characterized in that, include: A module for performing the method as described in any one of claims 13 to 21.

24. A device for transmitting acoustic wave signals, characterized in that, include: A processor for executing a computer program stored in a memory, causing the apparatus to perform the method as described in any one of claims 1 to 12; A communication interface, coupled to the processor, is used for inputting or outputting information.

25. A device for decoding acoustic signals, characterized in that, include: A processor for executing a computer program stored in a memory, causing the apparatus to perform the method as described in any one of claims 13 to 21; A communication interface, coupled to the processor, is used for inputting or outputting information.

26. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, causes the processor to perform the method of any one of claims 1 to 12, or causes the processor to perform the method of any one of claims 13 to 21.

27. A computer program product, characterized in that, When the computer program product is executed by a processor, the method of any one of claims 1 to 12 is performed, or the method of any one of claims 13 to 21 is performed.

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