Underwater detection and communication integrated system and method based on sinusoidal frequency modulation

Abstract

The application discloses an underwater detection and communication integrated system and method based on sinusoidal frequency modulation, and belongs to the field of underwater detection and communication. The system comprises an integrated module transmitting end responsible for signal transmission and echo signal receiving and processing, and an integrated module receiving end responsible for integrated signal receiving and communication processing. The integrated signal collected by the system is a sinusoidal frequency modulation signal after minimum frequency shift keying modulation. When the transmission signal is 1, the signal phase increases; when the transmission signal is 0, the signal phase decreases. The phase of the sinusoidal frequency modulation signal as a detection signal can carry transmission information, and underwater detection and underwater communication are associated. The binary communication information is stored in the phase of the detection signal in the form of minimum frequency shift keying. The underwater detection capability is realized, the communication between underwater platforms is completed, the integration of underwater detection and communication is realized, and the detection precision and communication quality are improved.

Description

Technical Field

[0001] This invention relates to the field of underwater detection and communication technology, and in particular to an integrated underwater detection and communication system and method based on sinusoidal frequency modulation. Background Technology

[0002] "Prosperity comes from the sea, decline from the sea"—the vigorous development of marine industries has become a broad global consensus. Integrated underwater detection and communication is an important direction for underwater cyber-physical systems. Initially applied in radar technology, this technology relied on electromagnetic waves for detection and communication. However, due to the exponential attenuation of electromagnetic waves underwater, radar-based integration cannot be directly applied underwater. Currently, underwater detection and communication systems are typically independent. Detection systems focus on acquiring target characteristics, azimuth, and range information using hydrophones and sonar, while communication systems prioritize high-performance communication protocols to address the narrow bandwidth, multipath effects, and attenuation characteristics of underwater acoustic channels, enabling information transmission between different terminals. The functions of underwater detection and communication systems overlap; independent design leads to competition for spectrum resources and energy consumption. Therefore, it is necessary to design an integrated underwater detection and communication method to address the spectrum resource and energy consumption competition caused by independent design.

[0003] In the prior art, Chinese invention patent CN115987744A discloses a method for designing and processing an integrated underwater detection and communication transmission signal. This method utilizes the strong orthogonality and good resolution of a generalized sinusoidal frequency modulated signal as a carrier. The integrated signal is obtained by multiplying the baseband signals of the detection and communication signals, allowing the communication signal to fully utilize the energy of the detection signal. A separation algorithm is then used to separate the received signal. While this method achieves the integration of underwater detection and communication signals, it is prone to distortion and interference in environments with significant underwater multipath effects and high noise. Furthermore, the direct application of this method to the baseband signal of the communication reduces the accuracy of underwater acoustic communication and increases the bit error rate.

[0004] Furthermore, Chinese invention patent CN116865875A discloses an integrated underwater detection and communication system, including an integrated signal transmitting module, a signal receiving module, and a received signal processing module. This invention, while ensuring normal communication performance, also incorporates active target detection capabilities. However, this system is prone to distortion and interference in environments characterized by significant underwater multipath effects and high noise levels. Additionally, the long duration of the transmitted communication signal increases the difficulty of capturing the detection echo.

[0005] Therefore, in the face of complex marine underwater environments, there is an urgent need to design a high-performance integrated underwater detection and communication system and method that takes into account both underwater detection and underwater communication. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide an integrated underwater detection and communication system and method based on sinusoidal frequency modulation. The binary communication information is stored in the phase of the detection signal in a minimum frequency shift keying manner. While realizing underwater detection capabilities, it also realizes communication between underwater platforms, thereby achieving the integration of underwater detection and communication based on sinusoidal frequency modulation, reducing competition between underwater detection and communication, and improving detection accuracy and communication quality.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0008] An integrated underwater detection and communication system based on sinusoidal frequency modulation is disclosed. The system includes an integrated module transmitter and an integrated module receiver. The integrated module transmitter is responsible for transmitting signals and receiving and processing echo signals. The integrated module receiver is responsible for receiving integrated signals and processing communication.

[0009] A further improvement of the technical solution of the present invention is that: the integrated module transmitter includes a transmitter transducer, an analog hydrophone, a first information processing unit, a first transmission control unit, a digital-to-analog / analog-to-digital conversion circuit, a signal modulation circuit, a first filtering and amplification circuit, and a waveform generator;

[0010] The first information processing unit is connected to the first transmission control unit, the first transmission control unit is connected to the signal modulation circuit, and the signal modulation circuit is connected to the waveform generator; the waveform generator outputs the signal waveform specified by the first information processing unit.

[0011] The waveform generator is connected to the transmitting transducer and is used to convert the electrical signal of the waveform generator into an acoustic signal.

[0012] The analog hydrophone is connected to the first filter amplifier circuit, the first filter amplifier circuit is connected to the digital-to-analog / analog-to-digital converter circuit, and the digital-to-analog / analog-to-digital converter circuit is connected to the first transmission control unit to receive echo signals.

[0013] The integrated module receiver includes a receiving transducer, a second filtering and amplifying circuit, a signal demodulation circuit, a second transmission control unit, and a second information processing unit.

[0014] The receiving transducer is connected to the second filtering and amplifying circuit to convert the integrated signal passing through the underwater acoustic channel into an electrical signal and process it.

[0015] The second filtering amplifier circuit is connected to the signal demodulation circuit, the signal demodulation circuit is connected to the second transmission control unit, and the second transmission control unit is connected to the second information processing unit, so as to demodulate the output signal of the second filtering amplifier circuit and transmit it to the second transmission control unit and the second information processing unit.

[0016] An integrated underwater detection and communication method based on sinusoidal frequency modulation is proposed. The integrated signal acquired by the system is a sinusoidal frequency modulated signal after minimum frequency shift keying modulation. When the transmitted signal is 1, the signal phase increases. When the transmitted signal is 0, the signal phase decreases. It enables the phase of the sinusoidal frequency modulation signal used as a detection signal to carry transmission information, and also links underwater detection and underwater communication.

[0017] A further improvement to the technical solution of the present invention is that the method specifically includes the following steps:

[0018] Step 1: Deploy integrated module transmitter and integrated module receiver in the target area;

[0019] Step 2: The transmitter transducer of the integrated module transmitter operates and transmits the sinusoidal frequency modulated detection waveform in a broadcast manner;

[0020] Step 3: If an echo is generated, a target exists within the target detection area, and step 4 is executed; otherwise, return to step 2 and continue the detection task.

[0021] Step 4: The analog hydrophone at the transmitter of the integrated module receives the echo signal, filters and amplifies the target signal through the first filtering and amplification circuit, and transmits the echo information to the first information processing unit through the digital-to-analog / analog-to-digital conversion circuit and the first transmission control unit.

[0022] Step 5: After receiving the echo signal, it indicates that the integrated module transmitter has detected the target. At this time, the integrated module transmitter begins to transmit the integrated waveform carrying communication information.

[0023] Step 6: If the receiving transducer of the integrated module receives the integrated signal emitted by the transmitting transducer, it indicates that a communication target exists in the area and Step 7 is executed; otherwise, it means that the detected target is not a communication target and it is necessary to return to Step 3 to continue searching for new communication targets.

[0024] Step 7: The receiving transducer of the integrated module receiver performs filtering, amplification and demodulation on the received integrated signal through the second filtering amplification circuit and the signal demodulation circuit to obtain communication information and transmit the communication information to the second transmission control unit and the second information processing unit.

[0025] Step 8: The integrated module receiver and the integrated module transmitter transmit the received information to the second information processing unit and the first information processing unit through the second transmission control unit and the first transmission control unit, respectively. After the second information processing unit and the first information processing unit process and display the corresponding information, the underwater detection and underwater communication functions of the integrated module are completed.

[0026] A further improvement to the technical solution of the present invention is as follows: In step 2, when the transmitting transducer of the integrated module transmitter transmits the sinusoidal frequency modulated detection waveform in a broadcast manner, a soundproof cover is placed around the transmitting transducer to prevent the simulated hydrophone from directly receiving the signal through the integrated module at the moment the transmitting transducer is working, so as to reduce the self-interference of the transmitting end of the integrated module; the first information processing unit controls the waveform generator to generate a sinusoidal frequency modulated signal through the first transmission control unit to drive the transmitting transducer, convert the electrical signal into an acoustic signal, and transmit it into the underwater acoustic channel.

[0027] A further improvement of the technical solution of the present invention is that: in step 4, after receiving the echo signal, the analog hydrophone at the transmitter of the integrated module converts the acoustic signal into an electrical signal, processes the signal through the first filtering and amplification circuit, and then transmits the echo signal collected by the analog hydrophone to the first information processing unit via a serial port through the digital-to-analog / analog-to-digital conversion circuit and the first transmission control unit.

[0028] A further improvement to the technical solution of the present invention is that, in step 5, the specific process is as follows:

[0029] After the integrated module transmitter detects the target, the first information processing unit writes the input information into the first transmission control unit in the form of an eight-bit binary number, and then adds the communication protocol to form the binary data information to be sent. Then, the binary data information to be sent is differentially encoded and converted into relative code to reduce interference between adjacent code elements.

[0030] The signal is then divided into two paths, I and Q, according to parity, and each path is multiplied by the carrier signal:

[0031] and

[0032] Where ω is the carrier center frequency and T is a single symbol period;

[0033] Then, by adding them together, we can obtain the modulated minimum frequency shift keying signal. The signal modulated by minimum frequency shift keying of the differentially encoded binary data information is as follows:

[0034]

[0035] Where A is the signal amplitude, N is one symbol period, and n is the number of sequence points, where n = 1, 2, 3, ...

[0036] a k For the data in the k-th symbol, This is the initial phase;

[0037] The expression for a sinusoidal frequency modulated signal is as follows:

[0038] S SFM (t)=A·exp{j(2πf c +βcos(2παt))t}

[0039] Where A is the signal amplitude; f c β is the center frequency; β is the modulation index, which determines the modulation amplitude of the frequency; α is the frequency modulation term, which determines the number of cycles contained in the frequency function of the signal pulse.

[0040] The integrated signal obtained by modulating the phase of the sinusoidal frequency modulation signal using minimum frequency shift keying is as follows:

[0041]

[0042] Where A is the signal amplitude, N is one symbol period, n is the number of sequence points and n = 1, 2, 3, ..., f c Let β be the center frequency, β be the modulation index, and α be the frequency modulation term. a k For the data in the k-th symbol, This is the initial phase;

[0043] The obtained integrated signal is sent to the transmitting transducer through the waveform generator inside the integrated module transmitter, thus completing the conversion of the electrical signal into an acoustic signal, and the information enters the underwater acoustic channel.

[0044] A further improvement of the technical solution of the present invention is as follows: In step 7, after the receiving transducer of the integrated module receives the integrated signal, it performs matched filtering to maximize the signal-to-noise ratio of the signal. Then, the filtered integrated signal and the reference sinusoidal frequency modulation signal are simultaneously input to the input of the phase-sensitive detection circuit to identify the phase of the modulation signal. When there is a phase difference between the two, the circuit will output a corresponding voltage. Then, the detected signal is differentially decoded to recover the original binary data information. The integrated module receiving end transmits the demodulated binary data information to the second transmission control unit. According to the communication protocol, the information transmitted by the integrated module transmitting end is transmitted to the second information processing unit, thus completing the underwater communication function.

[0045] The technological advancements achieved by this invention due to the adoption of the above technical solutions are as follows:

[0046] 1. The underwater detection and communication integrated system based on sinusoidal frequency modulation of this invention adopts minimum frequency shift keying phase modulation to carry communication information in the phase of the sinusoidal frequency modulated detection signal, thereby realizing the simultaneous underwater detection and underwater communication capabilities.

[0047] 2. The underwater detection and communication integrated method based on sinusoidal frequency modulation of the present invention can reduce the bit error rate of underwater communication while ensuring the accuracy of underwater detection.

[0048] 3. The integrated system design of this invention solves the problems of spectrum resource competition and energy consumption competition that exist in existing independent underwater detection and underwater communication, and improves the overall spectrum utilization and performance of the underwater system platform. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a flowchart of the underwater detection and communication integration method based on sinusoidal frequency modulation in this invention;

[0051] Figure 2 This is a schematic diagram illustrating the application of the underwater detection and communication integrated system based on sinusoidal frequency modulation in this invention.

[0052] Figure 3 This is a schematic diagram of the underwater detection and communication integrated system based on sinusoidal frequency modulation in this invention;

[0053] Figure 4 This is a flowchart of the integrated underwater detection and communication signal modulation and demodulation based on sinusoidal frequency modulation in this invention. Detailed Implementation

[0054] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification, claims and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products or devices.

[0055] See Figure 1 , Figure 2 , Figure 3 , Figure 4 The invention illustrates the integrated underwater detection and communication system and method based on sinusoidal frequency modulation, including the workflow of the integrated underwater detection and communication method based on sinusoidal frequency modulation, a schematic diagram of the integrated system application, the main components of the integrated module transmitter and receiver, and the modulation method of the fully shared waveform.

[0056] The invention will be further described below with reference to the accompanying drawings:

[0057] like Figure 2 , 3 As shown, an integrated underwater detection and communication system based on sinusoidal frequency modulation is disclosed. The system includes an integrated module transmitter and an integrated module receiver. The integrated module transmitter is responsible for transmitting signals and receiving and processing echo signals. The integrated module receiver is responsible for receiving integrated signals and processing communication.

[0058] Furthermore, the integrated module transmitter includes a transmitting transducer, an analog hydrophone, a first information processing unit, a first transmission control unit, a digital-to-analog / analog-to-digital conversion circuit, a signal modulation circuit, a first filtering and amplification circuit, and a waveform generator;

[0059] The first information processing unit is connected to the first transmission control unit, the first transmission control unit is connected to the signal modulation circuit, and the signal modulation circuit is connected to the waveform generator; the waveform generator outputs the signal waveform specified by the first information processing unit.

[0060] The waveform generator is connected to the transmitting transducer to convert the electrical signal of the waveform generator into an acoustic signal;

[0061] The analog hydrophone is connected to the first filter amplifier circuit, which is connected to the digital-to-analog / analog-to-digital converter circuit, which is connected to the first transmission control unit to receive the echo signal.

[0062] The integrated module receiver includes a receiving transducer, a second filtering and amplifying circuit, a signal demodulation circuit, a second transmission control unit, and a second information processing unit.

[0063] The receiving transducer is connected to the second filter amplifier circuit to convert the integrated signal passing through the underwater acoustic channel into an electrical signal and process it.

[0064] The second filter amplifier circuit is connected to the signal demodulation circuit, which is connected to the second transmission control unit. The second transmission control unit is connected to the second information processing unit to demodulate the output signal of the second filter amplifier circuit and transmit it to the second transmission control unit and the second information processing unit.

[0065] like Figure 1 As shown, an integrated underwater detection and communication method based on sinusoidal frequency modulation is proposed. The integrated signal acquired by the system is a sinusoidal frequency modulated signal after minimum frequency shift keying modulation. When the transmitted signal is 1, the signal phase increases. When the transmitted signal is 0, the signal phase decreases. It enables the phase of the sinusoidal frequency modulation signal used as a detection signal to carry transmission information, and also links underwater detection and underwater communication.

[0066] Specifically, the following steps are included:

[0067] Step 1: In the target detection and communication area, the selected water area should ideally be relatively open and spacious to appropriately reduce multipath effects and echo interference. Deploy the integrated module transmitter and integrated module receiver of the integrated system separately. For example... Figure 3 As shown, the transmitting transducer of the integrated module transmitter is responsible for sending the integrated signal, and the simulated hydrophone receives the integrated signal echo; the receiving transducer of the integrated module receiver is used to receive the information sent by the integrated module transmitter.

[0068] Step 2: After the integrated system is deployed, the integrated module transmitter is connected to the first information processing unit through the first transmission control unit, causing the transmitting transducer to broadcast a sinusoidal frequency modulated detection signal, such as... Figure 2 As shown.

[0069] Step 3: If the integrated module transmitter receives an echo, it means that there is an obstacle target in the detection area, and continue to step 4; otherwise, it means that there is no target in the detection area, and return to step 2 to continue detection.

[0070] Step 4: The analog hydrophone at the transmitter of the integrated module receives the echo signal and generates a voltage value. This voltage value, after passing through a matched filter circuit and an amplification circuit, is connected to a digital-to-analog / analog-to-digital converter circuit, transmitting the signal to the first transmission control unit. The first transmission control unit then transmits the information to the first information processing unit, such as... Figure 3 The integrated module transmitter is shown.

[0071] Step 5: When the received echo signal shows a significant amplitude change, it indicates that the integrated module transmitter has detected the obstacle target and has begun transmitting the integrated waveform carrying communication information. For example... Figure 3 , 4As shown, the first information processing unit first writes the information to be sent as binary data to the first transmission control unit via a serial port. After the first transmission control unit adds the communication protocol, it performs differential encoding and serial-to-parallel conversion on the binary data to reduce inter-symbol interference. The relative code of the binary data to be modulated is divided into two signals, I and Q, according to parity, and modulated separately. Then, they are added together to obtain the waveform of the binary data after minimum frequency shift keying (MSK) modulation, the expression of which is:

[0072]

[0073] in, a k For the data in the k-th symbol, This is the initial phase;

[0074] Next, the minimum frequency shift keying signal containing the communication information is modulated into the phase of the sinusoidal frequency modulation signal. The expression for the sinusoidal frequency modulation signal is:

[0075] S SFM (t)=exp{j(2πf c +βcos(2παt))t}

[0076] Among them, f c β is the center frequency; β is the modulation index, which determines the modulation amplitude of the frequency; α is the frequency modulation term, which determines the number of cycles contained in the frequency function of the signal pulse.

[0077] After modulation, an integrated signal is obtained, whose signal expression is:

[0078]

[0079] It also drives the underwater acoustic transducer to emit an integrated waveform via a waveform transmitter.

[0080] Step 6: As Figure 2 As shown, if the integrated module receiver receives the integrated waveform, it indicates that it is connected to the communication target and continues to execute step 7; otherwise, it indicates that the target connected to the integrated module transmitter is not the communication target, and returns to step 2 to retransmit the detection signal to find a new target.

[0081] Step 7, as follows Figure 3 As shown, after the receiving transducer at the receiving end of the integrated module receives the integrated signal, it first performs signal processing and information demodulation through a filtering and amplification circuit and a phase-sensitive detection circuit. The demodulated information is then transmitted to the second transmission control unit, and the information is transmitted to the second information processing unit according to the communication protocol.

[0082] Step 8: The integrated module receiver and the integrated module transmitter transmit the received information to the second information processing unit and the first information processing unit through the second transmission control unit and the first transmission control unit, respectively. After the second information processing unit and the first information processing unit process and display the corresponding information, the underwater detection and underwater communication functions of the integrated module are completed.

[0083] like Figure 2 As shown, this illustrates an application scenario for an integrated underwater detection and communication method based on sinusoidal frequency modulation. The transmitting transducer of the integrated module broadcasts detection signals. After the detection wave detects other targets, it generates an echo signal, but these other targets cannot obtain the communication information transmitted by the integrated module transmitter. Only when the integrated module transmitter transmits to the integrated module receiver can the receiver receive the integrated waveform transmitted by the integrated module transmitter and demodulate the information to complete the communication function.

[0084] like Figure 4 The diagram illustrates the modulation and demodulation process of an integrated underwater detection and communication signal based on sinusoidal frequency modulation. The integrated signal modulation process involves differential encoding, serial-to-parallel conversion, coherent carrier wave, and signal superposition of binary data information, followed by phase modulation onto the phase of a sinusoidal frequency modulated signal to form an integrated signal. The integrated demodulation process involves superimposing the integrated signal with underwater acoustic channel noise, first performing a matched filter amplification circuit to remove clutter interference and retain the target signal, then inputting it along with the sinusoidal frequency modulated signal into a phase-sensitive detection circuit to demodulate the information carried by the integrated signal. Finally, digital-to-analog conversion and differential decoding are used to obtain the final binary data information.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for integrated underwater detection and communication based on sinusoidal frequency modulation, characterized in that: The system used in the method includes an integrated module transmitter and an integrated module receiver; the integrated module transmitter is responsible for transmitting signals and receiving and processing echo signals; the integrated module receiver is responsible for receiving integrated signals and processing communication. The integrated signal acquired by the system is a sinusoidal frequency modulated signal after minimum frequency shift keying modulation. When the transmitted signal is 1, the signal phase increases. ; When the transmitted signal is 0, the signal phase decreases. This allows the phase of the sinusoidal frequency modulation signal, which serves as the detection signal, to carry transmission information, and also links underwater detection and underwater communication.

2. The underwater detection and communication integrated method based on sinusoidal frequency modulation according to claim 1, characterized in that: The method specifically includes the following steps: Step 1: Deploy integrated module transmitter and integrated module receiver in the target area; Step 2: The transmitter transducer of the integrated module transmitter operates and transmits the sinusoidal frequency modulated detection waveform in a broadcast manner; Step 3: If an echo is generated, a target exists within the target detection area, and step 4 is executed; otherwise, return to step 2 and continue the detection task. Step 4: The analog hydrophone at the transmitter of the integrated module receives the echo signal, filters and amplifies the target signal through the first filtering and amplification circuit, and transmits the echo information to the first information processing unit through the digital-to-analog / analog-to-digital conversion circuit and the first transmission control unit. Step 5: After receiving the echo signal, it indicates that the integrated module transmitter has detected the target. At this time, the integrated module transmitter begins to transmit the integrated waveform carrying communication information. Step 6: If the receiving transducer of the integrated module receives the integrated signal emitted by the transmitting transducer, it indicates that a communication target exists in the area and Step 7 is executed; otherwise, it means that the detected target is not a communication target and it is necessary to return to Step 3 to continue searching for new communication targets. Step 7: The receiving transducer of the integrated module receiver performs filtering, amplification and demodulation on the received integrated signal through the second filtering amplification circuit and the signal demodulation circuit to obtain communication information and transmit the communication information to the second transmission control unit and the second information processing unit. Step 8: The integrated module receiver transmits the received information to the second information processing unit through the second transmission control unit, and the integrated module transmitter transmits the received information to the first information processing unit through the first transmission control unit. After the second information processing unit and the first information processing unit process and display the corresponding information, the underwater detection and underwater communication functions of the integrated module are completed.

3. The underwater detection and communication integrated method based on sinusoidal frequency modulation according to claim 2, characterized in that: In step 2, when the transmitting transducer of the integrated module transmits the sinusoidal frequency modulated detection waveform in a broadcast manner, a soundproof cover is placed around the transmitting transducer to prevent the simulated hydrophone from directly receiving the signal through the integrated module at the moment the transmitting transducer is working, so as to reduce the self-interference of the transmitting end of the integrated module; the first information processing unit controls the waveform generator through the first transmission control unit to generate a sinusoidal frequency modulated signal to drive the transmitting transducer, convert the electrical signal into an acoustic signal, and transmit it into the underwater acoustic channel.

4. The underwater detection and communication integrated method based on sinusoidal frequency modulation according to claim 2, characterized in that: In step 4, after receiving the echo signal, the analog hydrophone at the transmitter of the integrated module converts the acoustic signal into an electrical signal. The signal is then processed by the first filtering and amplification circuit, and then transmitted to the first information processing unit via a serial port through the digital-to-analog / analog-to-digital conversion circuit and the first transmission control unit.

5. The underwater detection and communication integrated method based on sinusoidal frequency modulation according to claim 2, characterized in that: In step 5, the specific process is as follows: After the integrated module transmitter detects the target, the first information processing unit writes the input information into the first transmission control unit in the form of an eight-bit binary number, and then adds the communication protocol to form the binary data information to be sent. Then, the binary data information to be sent is differentially encoded and converted into relative code to reduce interference between adjacent code elements. The signal is then divided into two paths, I and Q, according to parity, and each path is multiplied by the carrier signal: and in It is the center frequency of the carrier. It is a single symbol period; Then, by adding them together, we can obtain the modulated minimum frequency shift keying signal. The signal modulated by minimum frequency shift keying of the differentially encoded binary data information is as follows: in The signal amplitude, One symbol period The number of points in the sequence and , , For the first Data in each code element This is the initial phase; The expression for a sinusoidal frequency modulated signal is as follows: in The signal amplitude; The center frequency; The modulation index determines the modulation amplitude of the frequency. The frequency modulation term determines the number of cycles contained in the frequency function of the signal pulse; The integrated signal obtained by modulating the phase of the sinusoidal frequency modulation signal using minimum frequency shift keying is as follows: in, The signal amplitude, One symbol period The number of points in the sequence and , For the center frequency, The modulation index, For frequency modulation terms, , For the first Data in each code element This is the initial phase; The obtained integrated signal is sent to the transmitting transducer through the waveform generator inside the integrated module transmitter, thus completing the conversion of the electrical signal into an acoustic signal, and the information enters the underwater acoustic channel.

6. The underwater detection and communication integrated method based on sinusoidal frequency modulation according to claim 2, characterized in that: In step 7, after the receiving transducer of the integrated module receives the integrated signal, it performs matched filtering to maximize the signal-to-noise ratio of the signal. Then, the filtered integrated signal and the reference sinusoidal frequency modulation signal are simultaneously input to the input of the phase-sensitive detection circuit to identify the phase of the modulation signal. When there is a phase difference between the two, the circuit will output the corresponding voltage. Then, the detected signal is differentially decoded to recover the original binary data information. The integrated module receiver transmits the demodulated binary data to the second transmission control unit, and then, according to the communication protocol, transmits the information transmitted by the integrated module transmitter to the second information processing unit, thus completing the underwater communication function.

7. The underwater detection and communication integrated method based on sinusoidal frequency modulation according to claim 1, characterized in that: The integrated module transmitter includes a transmitter transducer, an analog hydrophone, a first information processing unit, a first transmission control unit, a digital-to-analog / analog-to-digital conversion circuit, a signal modulation circuit, a first filtering and amplification circuit, and a waveform generator; The first information processing unit is connected to the first transmission control unit, the first transmission control unit is connected to the signal modulation circuit, and the signal modulation circuit is connected to the waveform generator, so that the waveform generator outputs the signal waveform specified by the first information processing unit; The waveform generator is connected to the transmitting transducer and is used to convert the electrical signal of the waveform generator into an acoustic signal. The analog hydrophone is connected to the first filter amplifier circuit, the first filter amplifier circuit is connected to the digital-to-analog / analog-to-digital converter circuit, and the digital-to-analog / analog-to-digital converter circuit is connected to the first transmission control unit to receive echo signals. The integrated module receiver includes a receiving transducer, a second filtering and amplifying circuit, a signal demodulation circuit, a second transmission control unit, and a second information processing unit. The receiving transducer is connected to the second filtering and amplifying circuit to convert the integrated signal passing through the underwater acoustic channel into an electrical signal and process it. The second filtering amplifier circuit is connected to the signal demodulation circuit, the signal demodulation circuit is connected to the second transmission control unit, and the second transmission control unit is connected to the second information processing unit, so as to demodulate the output signal of the second filtering amplifier circuit and transmit it to the second transmission control unit and the second information processing unit.

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