Inter-device communication method and system based on chirp acoustic waves

Abstract

The application provides a method and system for inter-device communication based on linear frequency modulation sound waves, and relates to the technical field of wireless communication, aiming to solve the problems of low rate and vulnerability to interference existing in the prior art sound wave communication method. The method applied to a sending device comprises the following steps: combining bit data streams corresponding to transmission information into different symbols; encoding each symbol according to the correspondence between the symbol and a linear frequency modulation signal to obtain different target linear frequency modulation signal segments, the time length and bandwidth of each target linear frequency modulation signal segment being the same, and the starting frequencies being different; splicing all the target linear frequency modulation signal segments into a target linear frequency modulation sound wave signal; and sending the target linear frequency modulation sound wave signal, so that a receiving device receives the target linear frequency modulation sound wave signal and obtains the transmission information through linear frequency modulation decoding.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, and in particular to a method and system for inter-device communication based on linear frequency modulation acoustic waves. BACKGROUND

[0002] With the rapid development of Internet of Things technology, the interconnection between a large number of devices puts higher requirements on communication technology, and high-speed and reliable wireless data transmission needs to be realized. However, current wireless communication technologies (such as Wi-Fi, Bluetooth, Zigbee, etc.) face severe challenges in some application scenarios. For example, in complex indoor environments or industrial scenarios with strong electromagnetic interference, radio signals are easily affected by severe attenuation, interference and multipath effects, resulting in a decline in communication quality and even interruption.

[0003] As a communication method based on mechanical waves, acoustic wave communication has unique advantages in complex electromagnetic environments and indoor environments due to its characteristics of being unaffected by electromagnetic interference. However, traditional acoustic wave communication technology usually uses acoustic wave signals of fixed frequency as carriers to modulate information on a single frequency for transmission. This method is easily affected by signal attenuation and multipath effects in complex channel conditions, resulting in limited communication rate and distance, making it difficult to meet the demand for high-speed and reliable communication in Internet of Things applications.

[0004] Therefore, it is an urgent technical problem to develop a new type of acoustic wave communication method that can overcome the defects of traditional acoustic wave communication technology, improve communication rate and reliability, and be suitable for complex environments. SUMMARY

[0005] In view of the above problems, the embodiments of the present application provide a method and system for inter-device communication based on linear frequency modulation acoustic waves to overcome the above problems or at least partially solve the above problems.

[0006] In a first aspect of the embodiments of the present application, a method for inter-device communication based on linear frequency modulation acoustic waves is disclosed, applied to a sending device, and the method comprises:

[0007] combining bit data streams corresponding to transmission information into different symbols;

[0008] encoding each symbol according to the correspondence between the symbol and a linear frequency modulation signal to obtain different target linear frequency modulation signal segments, each target linear frequency modulation signal segment having the same time length and bandwidth and different starting frequencies;

[0009] splicing all target linear frequency modulation signal segments into a target linear frequency modulation acoustic wave signal;

[0010] The target linear frequency modulation sound wave signal is transmitted so that a receiving device receives the target linear frequency modulation sound wave signal and obtains the transmission information through linear frequency modulation decoding.

[0011] Optionally, the bit data stream corresponding to the transmission information is combined into different symbols, including:

[0012] The transmission information and the data length of the transmission information are encoded into a bit data stream.

[0013] Each target number of bits in the bit data stream is combined into a symbol to obtain different symbols.

[0014] Optionally, each symbol is encoded according to the correspondence between the symbol and the linear frequency modulation signal to obtain different target linear frequency modulation signal segments, including:

[0015] According to the correspondence between the symbol and the linear frequency modulation signal, the linear frequency modulation signal corresponding to each symbol is determined, and the linear frequency modulation signal is one of a first linear frequency modulation signal, a second linear frequency modulation signal, a third linear frequency modulation signal, and a fourth linear frequency modulation signal, wherein the first linear frequency modulation signal, the second linear frequency modulation signal, the third linear frequency modulation signal, and the fourth linear frequency modulation signal have the same time length and bandwidth and different starting frequencies.

[0016] The symbol is encoded using the starting frequency of the linear frequency modulation signal to obtain a target linear frequency modulation signal segment.

[0017] Optionally, the starting frequency of the first linear frequency modulation signal is a first target frequency, and the frequency of the first linear frequency modulation signal increases from the first target frequency to a second target frequency within the time length, and the second target frequency is equal to the first target frequency plus a bandwidth.

[0018] The starting frequency of the second linear frequency modulation signal is a third target frequency, and the frequency of the second linear frequency modulation signal increases from the third target frequency to the second target frequency within the time length, and from the first target frequency to the third target frequency, and the third target frequency is equal to the first target frequency plus 1 / 4 times the bandwidth.

[0019] The starting frequency of the third linear frequency modulation signal is a fourth target frequency, and the frequency of the third linear frequency modulation signal increases from the fourth target frequency to the second target frequency within the time length, and from the first target frequency to the fourth target frequency, and the fourth target frequency is equal to the first target frequency plus 1 / 2 times the bandwidth.

[0020] The starting frequency of the fourth chirp signal is a fifth target frequency, and the frequency of the fourth chirp signal increases from the fifth target frequency to the second target frequency in a time length, and then increases from the first target frequency to the fifth target frequency, and the fifth target frequency is equal to the first target frequency plus 3 / 4 of the bandwidth.

[0021] Optionally, splicing all the target chirp signal segments into a target chirp sound wave signal comprises:

[0022] Splicing the target chirp signal segments according to a target order to obtain an initial target chirp sound wave signal, wherein the target order is determined according to the positions of the symbols corresponding to the bits in the bit data stream;

[0023] Adding a preamble at the front end of the initial target chirp sound wave signal to obtain the target chirp sound wave signal, wherein the preamble is used for the receiving device to detect the arrival of the target chirp sound wave signal.

[0024] In a second aspect, the embodiment of the present application discloses a device-to-device communication method based on a chirp sound wave, applied to a receiving device, and the method comprises:

[0025] Receiving a target chirp sound wave signal, wherein the target chirp sound wave signal is obtained by linear frequency modulation encoding and transmitting the transmission information by a sending device;

[0026] Splitting the target chirp sound wave signal into a plurality of target chirp signal segments, wherein the time length and the bandwidth of each target chirp signal segment are the same, and the starting frequencies are different;

[0027] Decoding the plurality of target chirp signal segments by using a chirp reference signal to obtain the starting frequency of each target chirp signal segment, wherein the time length and the bandwidth of the chirp reference signal are the same as the time length and the bandwidth of the target chirp signal segment;

[0028] According to the starting frequency, a corresponding symbol is determined, and the transmission information is obtained according to the symbol.

[0029] Optionally, the target chirp sound wave signal comprises a preamble; and splitting the target chirp sound wave signal into a plurality of target chirp signal segments comprises:

[0030] According to the preamble, a starting time of a target chirp signal segment is determined;

[0031] According to the starting time and the time length of the target chirp signal segment, the target chirp sound wave signal is split to obtain a plurality of target chirp signal segments.

[0032] Optionally, the multiple target chirp signal segments are decoded by using a chirp reference signal to obtain a starting frequency of each target chirp signal segment, comprising:

[0033] Each target chirp signal segment is multiplied by the chirp reference signal to obtain an intermediate chirp signal segment;

[0034] The intermediate chirp signal segment is subjected to fast Fourier transform to obtain a frequency spectrum, and a frequency component in the frequency spectrum is determined according to a starting frequency of the chirp reference signal and a starting frequency of the target chirp signal segment;

[0035] A sixth target frequency corresponding to an amplitude peak is determined from the frequency spectrum, and the sixth target frequency satisfies a conversion relationship determined by the starting frequency of the target chirp signal segment and the starting frequency of the chirp reference signal;

[0036] According to the sixth target frequency and the conversion relationship, the starting frequency of the target chirp signal segment is calculated.

[0037] Optionally, the chirp reference signal comprises a fifth chirp signal and a sixth chirp signal, and frequencies of the fifth chirp signal and the sixth chirp signal decrease linearly over time;

[0038] The starting frequency of the fifth chirp signal is a seventh target frequency, and the seventh target frequency is equal to a target initial frequency plus 1 times a bandwidth;

[0039] The starting frequency of the sixth chirp signal is an eighth target frequency, and the eighth target frequency is equal to the target initial frequency plus 2 times the bandwidth.

[0040] A third aspect of the embodiments of the present application discloses a device-to-device communication system based on a chirp sound wave, comprising a sending device and a receiving device, the sending device is configured to perform the steps of the device-to-device communication method based on the chirp sound wave according to the first aspect of the embodiments of the present application, and the receiving device is configured to perform the steps of the device-to-device communication method based on the chirp sound wave according to the first aspect of the embodiments of the present application.

[0041] The embodiments of the present application have the following advantages:

[0042] In the embodiment of the present application, by combining the bit data stream corresponding to the transmission information into different symbols, and encoding each symbol according to the correspondence between the symbol and the linear frequency modulation signal, different target linear frequency modulation signal segments are obtained, each target linear frequency modulation signal segment has the same time length and bandwidth, and different starting frequencies; all target linear frequency modulation signal segments are spliced into a target linear frequency modulation acoustic wave signal, and the target linear frequency modulation acoustic wave signal is sent, so that the receiving device receives the target linear frequency modulation acoustic wave signal, and obtains the transmission information through linear frequency modulation decoding. In this way, the transmission information is linear frequency modulation encoded into a target linear frequency modulation acoustic wave signal for transmission in a wider frequency band, so as to improve the anti-interference ability and transmission stability of the signal, thereby ensuring the transmission rate and reliability of the transmission information. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the description of the embodiments of the present application will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0044] Figure 1 is a step flow chart of a device-to-device communication method based on linear frequency modulation acoustic wave provided by the embodiments of the present application;

[0045] Figure 2 is a schematic diagram of the relationship between the frequency and time of a linear frequency modulation signal provided by the embodiments of the present application;

[0046] Figure 3 is a step flow chart of another device-to-device communication method based on linear frequency modulation acoustic wave provided by the embodiments of the present application;

[0047] Figure 4 is a schematic diagram of target linear frequency modulation signal segment decoding provided by the embodiments of the present application;

[0048] Figure 5 is a structural schematic diagram of a device-to-device communication system based on linear frequency modulation acoustic wave provided by the embodiments of the present application. DETAILED DESCRIPTION

[0049] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0050] This application provides a device-to-device communication method based on linear frequency modulated (LFM) sound waves. This method is applied to a transmitting device, which can be a portable or mobile terminal such as a smartphone, tablet, or gaming device. (See also...) Figure 1 As shown, Figure 1 This is a flowchart illustrating the steps of a device-to-device communication method based on linear frequency modulated sound waves, as provided in an embodiment of this application. Figure 1 As shown, the device-to-device communication method based on linear frequency modulated sound waves may specifically include steps S110 to S140:

[0051] Step S110: Combine the bit data stream corresponding to the transmitted information into different symbols.

[0052] At the start of communication, the sending device combines the bit data stream corresponding to the transmitted information into different symbols. The transmitted information can be text or image information. Specific encoding algorithms can encode the transmitted information into a bit data stream suitable for data communication, and then combine the bits in the bit data stream into different symbols. Encoding algorithms can be UTF-8, ASCII, etc. UTF-8 is a variable-length encoding method for the Unicode character set, using 1 to 4 bytes to represent characters. ASCII is a computer encoding method based on the Latin alphabet used to map characters to numbers.

[0053] Each symbol represents multiple bits in a bit data stream. For example, every two bits in a bit data stream can be combined into a symbol, in which case each symbol represents two bits; or, for another example, four bits in a bit data stream can be combined into a symbol, in which case each symbol represents four bits.

[0054] Step S120: Encode each symbol according to the correspondence between the symbol and the linear frequency modulated signal to obtain different target linear frequency modulated signal segments. Each target linear frequency modulated signal segment has the same time length and bandwidth, but a different starting frequency.

[0055] The linear frequency modulation signal is a linear frequency modulation signal with a linear increase in frequency over time, and different types of characters correspond to different linear frequency modulation signals, that is, each symbol corresponds to a unique linear frequency modulation signal. The time length and bandwidth of the linear frequency modulation signal corresponding to each symbol are the same, but the starting frequency is different. For example, the time length of each linear frequency modulation signal is 10 milliseconds, and the bandwidth is 18 kHz-22 kHz.

[0056] The correspondence between the symbol and the linear frequency modulation signal is constructed in advance. When transmitting the transmission information, for each combined symbol, the linear frequency modulation signal corresponding to each symbol is determined according to the correspondence between the symbol and the linear frequency modulation signal, and then the symbol is encoded based on the linear frequency modulation signal to obtain the corresponding target linear frequency modulation signal segment. Since the starting frequency of each target linear frequency modulation signal segment is different, the subsequent receiving device can determine the corresponding symbol according to the starting frequency of the target linear frequency modulation signal segment.

[0057] Step S130: splice all target linear frequency modulation signal segments into a target linear frequency modulation sound wave signal.

[0058] Specifically, the target linear frequency modulation signal segments are spliced into a complete target linear frequency modulation sound wave signal according to the order of the target linear frequency modulation signal segments, thereby ensuring the integrity and continuity of subsequent data transmission. For example, there are 4 target linear frequency modulation signal segments, and the 4 target linear frequency modulation signal segments are spliced to obtain 1 complete target linear frequency modulation sound wave signal.

[0059] Step S140: send the target linear frequency modulation sound wave signal, so that the receiving device receives the target linear frequency modulation sound wave signal and obtains the transmission information through linear frequency modulation decoding.

[0060] The sending device can send the target linear frequency modulation sound wave signal through a sound wave emitting device (for example, a loudspeaker or other sound wave emitter). After sending the target linear frequency modulation sound wave signal, the receiving device can receive the target linear frequency modulation sound wave signal through a sound wave receiving device (for example, a microphone or other sound wave receiver).

[0061] The receiving device linear frequency modulation decodes the received target linear frequency modulation sound wave signal to determine the starting frequency of each target linear frequency modulation signal segment. Since the starting frequency of each target linear frequency modulation signal segment is different, the corresponding symbol is determined according to the starting frequency, and finally the transmission information is restored.

[0062] By using the wideband characteristic of the linear frequency modulation signal of the sound wave, the linear frequency modulation coded transmission information is transmitted on a wider frequency band as the target linear frequency modulation sound wave signal, so as to improve the anti-interference ability and transmission stability of the signal, thereby ensuring the transmission rate and reliability of the transmission information. Especially in a complex multipath environment, excellent anti-interference ability and stability are exhibited, meeting the needs of the wireless communication system for high rate, high reliability and low power consumption.

[0063] The method can be applied to a short-distance, connectionless mobile device communication scenario, that is, the method can be used for information transmission before device-to-device communication is established. For example, for Bluetooth transmission, scanning is required before connection is established. By using the scheme of the embodiments of the present application, information required for Bluetooth connection can be directly transmitted to a receiving device by the target linear frequency modulation sound wave signal without establishing a connection between devices.

[0064] In combination with the above embodiments, in an embodiment, the embodiments of the present application also provide a device-to-device communication method based on a linear frequency modulation sound wave, in which the step S110 of "combining bit data streams corresponding to the transmission information into different symbols" specifically includes the sub-step S110-1 to the step S110-2:

[0065] Step S110-1: encoding the transmission information and the data length of the transmission information into bit data streams.

[0066] Step S110-2: combining each target number of bits in the bit data stream into a symbol to obtain different symbols.

[0067] In the embodiments of the present application, in order to avoid data loss, the data length and the data content (transmission information) are both encoded into target linear frequency modulation signal segments for transmission. Specifically, the transmission information is encoded into an initial bit data stream, and then the bit corresponding to the data length is added to the initial bit data stream to obtain an encoded bit data stream, so as to be suitable for digital communication. The encoding of the transmission information and the data length of the transmission information into bit data streams is achieved by a specific encoding algorithm, for example, the UTF-8, ASCII, etc. algorithm.

[0068] Each target number of bits in the bit data stream is taken as a symbol, and according to the different target numbers, the corresponding symbol types are also different. The target number can be flexibly set according to actual conditions. For example, each 2-bit bit is combined into a symbol to form 4 different symbols, and for another example, each 4-bit bit is combined into a symbol to form 2 different symbols.

[0069] Thus, by encoding the data length and transmission information into a bit data stream, combining different symbols, and linear frequency modulation encoding different symbols into target linear frequency acoustic wave signals for transmission, the receiving device can determine the integrity of the received data based on the data length information, avoiding data loss.

[0070] In combination with the above embodiments, in an embodiment, the application also provides a linear frequency modulation acoustic wave-based inter-device communication method, in which the step S120 of "encoding each symbol according to the correspondence between the symbol and the linear frequency signal to obtain different target linear frequency signal segments" specifically includes sub-steps S120-1 to S120-2:

[0071] Step S120-1: determining the linear frequency signal corresponding to each symbol according to the correspondence between the symbol and the linear frequency signal, the linear frequency signal being one of a first linear frequency signal, a second linear frequency signal, a third linear frequency signal, and a fourth linear frequency signal, the first linear frequency signal, the second linear frequency signal, the third linear frequency signal, and the fourth linear frequency signal being linear frequency signals with the same time length and bandwidth and different starting frequencies.

[0072] Step S120-2: encoding the symbol using the starting frequency of the linear frequency signal to obtain a target linear frequency signal segment.

[0073] In the application, each 2-bit in the bit data stream is combined into a symbol, and there are 4 different symbols (for example, the 4 symbols can be represented as 0, 1, 2, and 3), each symbol corresponding to a different linear frequency signal, and there are 4 linear frequency signals, i.e., a first linear frequency signal, a second linear frequency signal, a third linear frequency signal, and a fourth linear frequency signal.

[0074] For each symbol, the linear frequency signal corresponding to the symbol is determined according to the correspondence between the symbol and the linear frequency signal, and the symbol is encoded using the starting frequency of the linear frequency signal to obtain a target linear frequency signal segment.

[0075] Since the starting frequencies of each linear frequency signal are different, the starting frequencies of the target linear frequency signal segments obtained by encoding are also different. Thus, the receiving device can determine the corresponding symbol according to the starting frequency of the target linear frequency signal segment, and further restore the transmission information.

[0076] Specifically, the starting frequency of the first linear frequency signal is a first target frequency, and the frequency of the first linear frequency signal increases from the first target frequency to a second target frequency within the time length, and the second target frequency is equal to the first target frequency plus the bandwidth.

[0077] The starting frequency of the second chirp signal is a third target frequency, and the frequency of the second chirp signal increases from the third target frequency to the second target frequency in a time length, and then increases from the first target frequency to the third target frequency, wherein the third target frequency is equal to the first target frequency plus 1 / 4 of the bandwidth;

[0078] The starting frequency of the third chirp signal is a fourth target frequency, and the frequency of the third chirp signal increases from the fourth target frequency to the second target frequency in a time length, and then increases from the first target frequency to the fourth target frequency, wherein the fourth target frequency is equal to the first target frequency plus 1 / 2 of the bandwidth;

[0079] The starting frequency of the fourth chirp signal is a fifth target frequency, and the frequency of the fourth chirp signal increases from the fifth target frequency to the second target frequency in a time length, and then increases from the first target frequency to the fifth target frequency, wherein the fifth target frequency is equal to the first target frequency plus 3 / 4 of the bandwidth.

[0080] For example, Figure 2 is a schematic diagram of the relationship between the frequency and time of a chirp signal provided by an embodiment of the present application. Wherein, Figure 2 (a) in (a) illustrates the relationship between the frequency and time of a first chirp signal, the frequency of the first chirp signal increases from a first target frequency (f1) ) to a second target frequency (f2) ) in a time length, wherein B is the bandwidth. Figure 2 (b) in (b) illustrates the relationship between the frequency and time of a second chirp signal, the frequency of the second chirp signal increases from a third target frequency (f3) ) to the second target frequency (f2) ) in a time length, and then the frequency becomes the first target frequency (f1) ), and increases from the first target frequency (f1) ) to the third target frequency (f3) ). Figure 2 (c) in (c) illustrates the relationship between the frequency and time of a third chirp signal, the frequency of the third chirp signal increases from a fourth target frequency (f4) 2) to the second target frequency (f2) ) in a time length, and then the frequency becomes the first target frequency (f1) ), and increases from the first target frequency (f1) ) to the fourth target frequency (f4) 2). Figure 2(d) illustrates the relationship between the frequency and time of the fourth linear frequency modulated signal. The frequency of the fourth linear frequency modulated signal changes from the fifth target frequency over the time length. After increasing to the second target frequency ( The frequency becomes the first target frequency ( And from the first target frequency ( Increase to the fifth target frequency ( ).

[0081] In this way, by utilizing the wideband characteristics of the linear frequency modulated (LFM) signal of the sound wave, the transmitted information is linearly frequency modulated and encoded into a target LFM sound wave signal for transmission over a wider frequency band, thereby improving the signal's anti-interference capability and transmission stability, and thus ensuring the transmission rate and reliability of the transmitted information.

[0082] In conjunction with the above embodiments, in one embodiment, this application also provides a device-to-device communication method based on linear frequency modulated (LFM) sound waves. In this method, the step S130 above, "splitting all target LFM signal segments into a target LFM sound wave signal," specifically includes sub-steps S130-1 to S130-2:

[0083] Step S130-1: The target linear frequency modulated signal segments are spliced ​​together according to the target order to obtain the initial target linear frequency modulated sound wave signal. The target order is determined according to the position of the bit corresponding to the symbol in the bit data stream.

[0084] Step S130-2: Add a preamble to the front end of the initial target linear frequency modulated (LFM) acoustic signal to obtain the target LFM acoustic signal. The preamble is used by the receiving device to detect the arrival of the target LFM acoustic signal.

[0085] In this embodiment of the application, the target order is determined according to the position of the bit corresponding to the symbol in the bit data stream. For example, if every two bits in the bit data stream are combined into a symbol, then the 1st and 2nd bits can be combined into symbol 0, the 3rd and 4th bits into symbol 1, the 5th and 6th bits into symbol 2, and the 7th and 8th bits into symbol 3. Here, symbol 0 is encoded as target linear frequency modulation (LFM) signal segment 0, symbol 1 is encoded as target LFM signal segment 1, symbol 2 is encoded as target LFM signal segment 2, and symbol 3 is encoded as target LFM signal segment 3. Then the target order can be: target LFM signal segment 0, target LFM signal segment 1, target LFM signal segment 2, and target LFM signal segment 3.

[0086] A preamble is a preset, fixed signal frequency band. It is used by the receiving device for packet detection. Specifically, the receiving device detects the arrival of a target LFM acoustic signal by using the preamble, adding it to the beginning of the initial target LFM acoustic signal to obtain the complete target LFM acoustic signal. During communication, if the receiving device detects the preamble, it indicates that the transmitting device has sent the target LFM acoustic signal, and the receiving device begins receiving the target LFM acoustic signal.

[0087] By employing the technical solution of this application embodiment, all target linear frequency modulated (LFM) signal segments corresponding to the transmitted information (symbol) are spliced ​​into a complete target LFM acoustic wave signal. The wide bandwidth characteristics of the target LFM acoustic wave signal can ensure the anti-interference capability and transmission stability of the transmission. Furthermore, by adding a preamble to the target LFM acoustic wave signal, the receiving device can receive the target LFM acoustic wave signal by detecting the preamble. Therefore, in connectionless communication scenarios, fast and stable communication between devices can be achieved.

[0088] This application provides a device-to-device communication method based on linear frequency modulated (LFM) sound waves. This method is applied to a receiving device, which can be a portable or mobile terminal such as a smartphone, tablet, or gaming device. (See also...) Figure 3 As shown, Figure 3 This is a flowchart illustrating the steps of another device-to-device communication method based on linear frequency modulated sound waves provided in an embodiment of this application. Figure 3 As shown, the device-to-device communication method based on linear frequency modulated sound waves may specifically include steps S310 to S340:

[0089] Step S310: Receive the target linear frequency modulated acoustic wave signal, wherein the target linear frequency modulated acoustic wave signal is obtained by the transmitting device through linear frequency modulation encoding of the transmitted information and then transmitted.

[0090] The receiving device can receive the target linear frequency modulated (LFM) sound wave signal via a sound wave receiving device (e.g., a microphone or other sound wave receiver). In some embodiments, the target LFM sound wave signal carries a preamble, and the receiving device detects the target LFM sound wave signal through the preamble, thereby receiving the target LFM sound wave signal.

[0091] In some embodiments, after receiving the target linear frequency modulated (LFM) acoustic signal, the receiving device stores the target LFM acoustic signal in a buffer, and subsequently reads the target LFM acoustic signal from the buffer for decoding to restore the transmitted information.

[0092] Step S320: The target linear frequency modulated (LFM) acoustic wave signal is split into multiple target LFM signal segments, each of which has the same time length and bandwidth but a different starting frequency.

[0093] The target linear frequency modulation sound wave signal is composed of a plurality of target linear frequency modulation signal segments spliced in sequence, and each target linear frequency modulation signal segment has the same time length, so that the receiving device splits the signal segments according to a fixed time length after receiving the target linear frequency modulation sound wave signal, and obtains a plurality of target linear frequency modulation signal segments.

[0094] Step S330: decoding the plurality of target linear frequency modulation signal segments by using a linear frequency modulation reference signal to obtain the starting frequency of each target linear frequency modulation signal segment, wherein the time length and the bandwidth of the linear frequency modulation reference signal are the same as those of the target linear frequency modulation signal segment.

[0095] The linear frequency modulation reference signal is a linear frequency modulation signal with a linearly decreasing frequency over time, which is used to process each target linear frequency modulation signal segment to determine the starting frequency of the target linear frequency modulation signal segment.

[0096] Step S340: determining the corresponding symbol according to the starting frequency, and obtaining the transmission information according to the symbol.

[0097] Since the starting frequency of each target linear frequency modulation signal segment is different, the corresponding symbol can be determined according to the correspondence between the symbol and the linear frequency modulation signal, and the starting frequency, and the transmission information can be finally restored.

[0098] The technical scheme of the embodiment of the present application linearly frequency modulates the transmission information into a target linear frequency modulation sound wave signal for transmission, and a receiving device decodes the received target linear frequency modulation sound wave signal to obtain the transmission information. In this way, the wideband characteristics of the linear frequency modulation signal of the sound wave are used to linearly frequency modulate the transmission information into a target linear frequency modulation sound wave signal for transmission in a wider frequency band, so as to improve the anti-interference ability and transmission stability of the signal, thereby ensuring the transmission rate and reliability of the transmission information. Especially in a complex multipath environment, excellent anti-interference ability and stability are exhibited, meeting the needs of wireless communication systems for high rate, high reliability and low power consumption.

[0099] In combination with the above embodiments, in an embodiment, the embodiment of the present application also provides a device-to-device communication method based on a linear frequency modulation sound wave, in which the target linear frequency modulation sound wave signal includes a preamble, and the step S320 of "splitting the target linear frequency modulation sound wave signal into a plurality of target linear frequency modulation signal segments" specifically includes sub-steps S320-1 to S320-2:

[0100] Step S320-1: determining the starting time of the target linear frequency modulation signal segment according to the preamble.

[0101] Step S320-2: splitting the target linear frequency modulated acoustic wave signal according to the starting time and the time length of the target linear frequency modulated signal segment, to obtain a plurality of target linear frequency modulated signal segments.

[0102] In the embodiments of the present application, the preamble is located at the front end of the target linear frequency modulated acoustic wave signal, and the starting time of the target linear frequency modulated signal segment (data packet) can be determined according to the preamble. Since the time length of each target linear frequency modulated signal segment is the same, and the target linear frequency modulated signal segments are spliced in order, after the starting time is determined, the target linear frequency modulated acoustic wave signal can be split into a plurality of target linear frequency modulated signal segments according to the time length of the target linear frequency modulated signal segment.

[0103] For example, for the target linear frequency modulated acoustic wave signal 1, the starting time of the target linear frequency modulated signal segment is 5 milliseconds, and the time length is 10 milliseconds. Therefore, every 10 milliseconds of the signal segment corresponding to the 5 milliseconds of the target linear frequency modulated acoustic wave signal 1 is a target linear frequency modulated signal segment.

[0104] In this way, a plurality of target linear frequency modulated signal segments representing different symbols are split from the target linear frequency modulated acoustic wave signal, so as to restore the transmission information based on the target linear frequency modulated signal segment, and realize the information transmission between the sending device and the receiving device.

[0105] In combination with the above embodiments, in an embodiment, the embodiments of the present application also provide a device-to-device communication method based on linear frequency modulated acoustic waves. In the method, the step S330 of "decoding the plurality of target linear frequency modulated signal segments by using the linear frequency modulated reference signal to obtain the starting frequency of each target linear frequency modulated signal segment" specifically includes sub-steps S330-1 to S330-4:

[0106] Step S330-1: multiplying each target linear frequency modulated signal segment with the linear frequency modulated reference signal to obtain an intermediate linear frequency modulated signal segment.

[0107] Step S330-2: performing fast Fourier transform on the intermediate linear frequency modulated signal segment to obtain a frequency spectrum, and the frequency components in the frequency spectrum are determined according to the starting frequency of the linear frequency modulated reference signal and the starting frequency of the target linear frequency modulated signal segment.

[0108] Step S330-3: determining a sixth target frequency corresponding to an amplitude peak from the frequency spectrum, and the sixth target frequency satisfies a conversion relationship determined by the starting frequency of the target linear frequency modulated signal segment and the starting frequency of the linear frequency modulated reference signal.

[0109] Step S330-4: calculating the starting frequency of the target chirp signal segment according to the sixth target frequency and the conversion relationship.

[0110] In the embodiment of the present application, the frequency of the target chirp signal segment increases linearly with time, and the frequency of the chirp reference signal decreases linearly with time. Since the time length of the target chirp signal segment and the chirp reference signal is the same, the maximum frequency (i.e. the sixth target frequency corresponding to the peak of the frequency spectrum amplitude) of the intermediate chirp signal segment is related to the starting frequency of the target chirp signal segment and the starting frequency of the chirp reference signal, i.e. the sixth target frequency satisfies the conversion relationship determined by the starting frequency of the target chirp signal segment and the starting frequency of the chirp reference signal. Thus, the starting frequency of the target chirp signal segment can be calculated based on the maximum frequency and the starting frequency of the chirp reference signal.

[0111] The frequency information of the intermediate chirp signal segment, i.e. the frequency spectrum, is captured by performing fast Fourier transform on the intermediate chirp signal segment. Then, the starting frequency of the target chirp signal segment is calculated according to the frequency corresponding to the peak of the frequency spectrum amplitude (i.e. the maximum frequency).

[0112] Specifically, the chirp reference signal includes a fifth chirp signal and a sixth chirp signal, the frequency of which decreases linearly with time; the starting frequency of the fifth chirp signal is a seventh target frequency, which is equal to the target initial frequency plus 1 times the bandwidth; the starting frequency of the sixth chirp signal is an eighth target frequency, which is equal to the target initial frequency plus 2 times the bandwidth.

[0113] For example, the fifth chirp signal and the sixth chirp signal can be represented as:

[0114] ,

[0115] ,

[0116] wherein t represents the current time, f0 represents the target initial frequency, which is set according to the actual situation, T represents the time length, and B represents the bandwidth; f7 represents the seventh target frequency, i.e. the starting frequency of the fifth chirp signal; f8 represents the eighth target frequency, i.e. the starting frequency of the sixth chirp signal.

[0117] As shown in Figure 4 , Figure 4is a schematic diagram of target linear frequency modulation signal segment decoding provided by an embodiment of the present application, and the process of decoding according to the fifth linear frequency modulation signal and the sixth linear frequency modulation signal is as follows: the fifth linear frequency modulation signal and the sixth linear frequency modulation signal are added to synthesize a linear frequency modulation reference signal, which is a complex signal. The linear frequency modulation reference signal is multiplied by a target linear frequency modulation signal segment to obtain an intermediate linear frequency modulation signal segment, and the intermediate linear frequency modulation signal segment is subjected to fast Fourier transform to obtain a frequency spectrum, frequency components in the frequency spectrum include three frequency components determined according to a starting frequency of the linear frequency modulation reference signal and a starting frequency of the target linear frequency modulation signal segment, and the three frequency components are , , wherein represents the starting frequency of the target linear frequency modulation signal segment.

[0118] The first linear frequency modulation signal, the second linear frequency modulation signal, the third linear frequency modulation signal and the fourth linear frequency modulation signal can all be divided into two signal segments (i.e., a first segment target linear frequency modulation signal segment and a second segment target linear frequency modulation signal segment ), and the frequencies of the two signal segments are respectively:

[0119] ,

[0120] ,

[0121] Since the two signals multiplied are both complex signals, the frequency of the signal obtained by multiplication is the sum of the frequencies of the two signals, and therefore, signal multiplication will generate the following frequency components.

[0122] The first segment target linear frequency modulation signal segment is multiplied by the linear frequency modulation reference signal, and the result can be represented as:

[0123] ,

[0124] ,

[0125] wherein represents the multiplication result of the first segment target linear frequency modulation signal segment and the fifth linear frequency modulation signal , represents the multiplication result of the first segment target linear frequency modulation signal segment and the sixth linear frequency modulation signal .

[0126] The second segment target linear frequency modulation signal segment is multiplied by the linear frequency modulation reference signal, and the result can be represented as:

[0127] ,

[0128] ,

[0129] wherein, represents the multiplication result of the second segment target linear frequency modulation signal segment and the fifth linear frequency modulation signal , represents the multiplication result of the second segment target linear frequency modulation signal segment and the sixth linear frequency modulation signal .

[0130] Since both segments of the target linear frequency modulation signal segment will generate component, therefore, the maximum amplitude, the sixth target frequency corresponding to the maximum amplitude is , and the conversion relationship satisfied by the sixth target frequency is: , then according to the conversion relationship, the starting frequency of the target linear frequency modulation signal segment can be calculated.

[0131] The technical scheme of the embodiment of the present application uses the linear frequency modulation reference signal to realize signal demodulation of each target linear frequency modulation signal segment, multiplies the target linear frequency modulation signal segment and the linear frequency modulation reference signal, and performs Fourier transform, determines the starting frequency of the target linear frequency modulation signal segment through the frequency peak value corresponding to the maximum amplitude, and then demodulates the symbol to restore the transmission information based on the symbol. In this way, the wideband characteristics of the linear frequency modulation signal of the sound wave are used, the transmission information is linear frequency modulation coded into the target linear frequency modulation sound wave signal for transmission in a wider frequency band, so as to improve the anti-interference ability and transmission stability of the signal, thereby ensuring the transmission rate and reliability of the transmission information.

[0132] The embodiment of the present application also provides an inter-device communication system based on linear frequency modulation sound waves. Referring to FIG. Figure 5 , Figure 5 is a structural schematic diagram of an inter-device communication system based on linear frequency modulation sound waves provided by the embodiment of the present application. The system 500 includes a sending device 510 and a receiving device 520, the sending device 510 is used for the steps of the inter-device communication method based on linear frequency modulation sound waves performed by the sending device end in the above embodiment, and the receiving device 520 is used for the steps of the inter-device communication method based on linear frequency modulation sound waves performed by the receiving device end in the above embodiment.

[0133] The inter-device communication system based on linear frequency modulation sound waves has the same advantages as the inter-device communication method based on linear frequency modulation sound waves described above, and details and advantages of the inter-device communication method based on linear frequency modulation sound waves have been described in detail in the above embodiment, and will not be described here.

[0134] The various embodiments in the specification are described in progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts between the embodiments can be mutually referred to.

[0135] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, systems according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminals to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminals generate a device for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The functions specified in one or more flows and / or blocks

[0136] Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications to the embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0137] Finally, it is to be understood that the phraseology or terminology such as "comprising", "including", "containing", or "consisting of" etc., is to be construed in its most expansive form, namely, it is to be construed to include the possibility of comprising, consisting of, containing or consisting essentially of the elements or steps listed thereafter, in addition to the elements or steps already present. In other words, the term "comprising" should not be understood to be limited to the recitation of elements or steps already present in the process, method, article, or apparatus, but to the possibility that the process, method, article, or apparatus might include additional elements or steps, in addition to those already present.

[0138] The above provides a kind of linear frequency modulation sound wave-based inter-device communication method and system provided in the application, the principle and implementation mode of the application are described in this paper by applying specific examples, the above example is only for helping to understand the method of the application and its core idea;For the general technical personnel in the art, according to the idea of the application, there will be changes in specific implementation mode and application range, as described above, the content of the specification should not be understood as the limitation of the application.

Claims

1. A method for inter-device communication based on chirp acoustic waves, characterized in that, The method is applied to a sending device and comprises the following steps: combining bit data streams corresponding to transmission information into different symbols; encoding each symbol according to a corresponding relationship between the symbol and a linear frequency modulation signal to obtain different target linear frequency modulation signal segments, each target linear frequency modulation signal segment having the same time length and bandwidth and different starting frequencies; splicing all the target linear frequency modulation signal segments into a target linear frequency modulation acoustic wave signal; sending the target linear frequency modulation acoustic wave signal so that a receiving device receives the target linear frequency modulation acoustic wave signal and obtains the transmission information through linear frequency modulation decoding; wherein the encoding of each symbol according to the corresponding relationship between the symbol and the linear frequency modulation signal to obtain different target linear frequency modulation signal segments comprises: determining a linear frequency modulation signal corresponding to each symbol according to the corresponding relationship between the symbol and the linear frequency modulation signal, the linear frequency modulation signal being one of a first linear frequency modulation signal, a second linear frequency modulation signal, a third linear frequency modulation signal and a fourth linear frequency modulation signal, the first linear frequency modulation signal, the second linear frequency modulation signal, the third linear frequency modulation signal and the fourth linear frequency modulation signal being linear frequency modulation signals having the same time length and bandwidth and different starting frequencies; and encoding the symbol using the starting frequency of the linear frequency modulation signal to obtain a target linear frequency modulation signal segment; wherein the starting frequency of the first linear frequency modulation signal is a first target frequency, and the frequency of the first linear frequency modulation signal increases from the first target frequency to a second target frequency within the time length, the second target frequency being equal to the first target frequency plus the bandwidth; the starting frequency of the second linear frequency modulation signal is a third target frequency, and the frequency of the second linear frequency modulation signal increases from the third target frequency to the second target frequency within the time length, and then increases from the first target frequency to the third target frequency, the third target frequency being equal to the first target frequency plus 1 / 4 of the bandwidth; the starting frequency of the third linear frequency modulation signal is a fourth target frequency, and the frequency of the third linear frequency modulation signal increases from the fourth target frequency to the second target frequency within the time length, and then increases from the first target frequency to the fourth target frequency, the fourth target frequency being equal to the first target frequency plus 1 / 2 of the bandwidth; the starting frequency of the fourth linear frequency modulation signal is a fifth target frequency, and the frequency of the fourth linear frequency modulation signal increases from the fifth target frequency to the second target frequency within the time length, and then increases from the first target frequency to the fifth target frequency, the fifth target frequency being equal to the first target frequency plus 3 / 4 of the bandwidth.

2. The chirp-based inter-device communication method according to claim 1, wherein, The method comprises the following steps: combining bit data streams corresponding to transmission information into different symbols; encoding the transmission information and the data length of the transmission information into a bit data stream; 3. The chirp-based inter-device communication method according to claim 1 or 2, wherein, combining each target number of bits in the bit data stream into a symbol to obtain different symbols. The method comprises the following steps: Splicing target linear frequency modulation signal segments according to a target order to obtain an initial target linear frequency modulation sound wave signal, the target order being determined according to the positions of the symbols corresponding to the bits in the bit data stream; Adding a preamble at the front end of the initial target linear frequency modulation sound wave signal to obtain the target linear frequency modulation sound wave signal, the preamble being used for the receiving device to detect the arrival of the target linear frequency modulation sound wave signal.

4. A method for inter-device communication based on chirp acoustic waves, characterized in that, The method is applied to a receiving device, and the method comprises: Receiving a target linear frequency modulation sound wave signal, the target linear frequency modulation sound wave signal being obtained by linear frequency modulation encoding and sending of transmission information by a sending device; Splitting the target linear frequency modulation sound wave signal into a plurality of target linear frequency modulation signal segments, each target linear frequency modulation signal segment having the same time length and bandwidth and different starting frequencies; Decoding the plurality of target linear frequency modulation signal segments by using a linear frequency modulation reference signal to obtain the starting frequencies of each target linear frequency modulation signal segment, the linear frequency modulation reference signal having the same time length and bandwidth as the target linear frequency modulation signal segments; Determining corresponding symbols according to the starting frequencies and obtaining the transmission information according to the symbols; Decoding the plurality of target linear frequency modulation signal segments by using a linear frequency modulation reference signal to obtain the starting frequencies of each target linear frequency modulation signal segment, comprising: Multiplying each target linear frequency modulation signal segment by the linear frequency modulation reference signal to obtain an intermediate linear frequency modulation signal segment; wherein the linear frequency modulation reference signal comprises a fifth linear frequency modulation signal and a sixth linear frequency modulation signal, the frequencies of which decrease linearly with time; the starting frequency of the fifth linear frequency modulation signal is a seventh target frequency, which is equal to a target initial frequency plus 1 times the bandwidth; the starting frequency of the sixth linear frequency modulation signal is an eighth target frequency, which is equal to the target initial frequency plus 2 times the bandwidth; Performing fast Fourier transform on the intermediate linear frequency modulation signal segment to obtain a frequency spectrum, the frequency components in the frequency spectrum being determined according to the starting frequencies of the linear frequency modulation reference signal and the target linear frequency modulation signal segment; A sixth target frequency corresponding to an amplitude peak in the frequency spectrum is determined, the sixth target frequency satisfying a conversion relationship determined by a starting frequency of the target chirp signal segment and a starting frequency of the chirp reference signal, the conversion relationship being expressed as: , denotes a starting frequency of a target chirp signal segment, denotes a sixth target frequency, denotes a target initial frequency, and B denotes a bandwidth; According to the sixth target frequency and the conversion relationship, the starting frequency of the target linear frequency modulation signal segment is calculated.

5. The chirp-based inter-device communication method according to claim 4, wherein, The target linear frequency modulation sound wave signal comprises a preamble; splitting the target linear frequency modulation sound wave signal into a plurality of target linear frequency modulation signal segments comprises: Determining the starting time of a target linear frequency modulation signal segment according to the preamble; Splitting the target linear frequency modulation sound wave signal according to the starting time and the time length of the target linear frequency modulation signal segment to obtain a plurality of target linear frequency modulation signal segments.

6. A chirp-based inter-device communication system, characterized in that The sending device is used to perform the steps of the linear frequency modulation sound wave-based device-to-device communication method of any one of claims 1-3, and the receiving device is used to perform the steps of the linear frequency modulation sound wave-based device-to-device communication method of any one of claims 4-5.

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