Underwater acoustic communication device having wireless energy harvesting function, and underwater acoustic communication method

Abstract

Disclosed in the present invention are an underwater acoustic communication device having a wireless energy harvesting function, and an underwater acoustic communication method. The underwater acoustic communication device is composed of a hydrophone, an on-duty circuit module, a received information processing module, an energy harvesting module, an energy storage module, a single-chip microcomputer minimum system, a data storage unit, a sent information processing module, a power amplifier module, an impedance matching circuit, a loudspeaker, a sensor, and an interface. According to the underwater acoustic communication device having the wireless energy harvesting function in the present invention, vibration energy caused by acoustic waves in a water body can be converted into electrical energy, and the electrical energy is stored in the energy storage module, so that energy is provided for all the low-energy-consumption modules in the device, the service life of a power supply of the whole underwater acoustic communication device can be prolonged, and the frequency of battery recycling can be reduced. The device can also receive and decode useful signals, and report anomaly data to a target node when the sensor collects the anomaly data, and is suitable for long-time underwater operation.

Description

Underwater acoustic communication device and method with wireless energy collection function Technical Field

[0001] The present invention relates to the technical field of underwater acoustic communication, and in particular to an underwater acoustic communication device and method with a wireless energy collection function. Background Art

[0002] With humanity's deepening exploration of the ocean, underwater acoustic communication technology has found widespread application in both military and civilian fields. Due to the industry's increasing demands for communication distance and quality, the power consumption of underwater acoustic communication equipment has also increased accordingly. This undoubtedly poses a severe challenge to the size and lifespan of the device's batteries, requiring frequent battery replacement to maintain normal operation of the device underwater. Wireless energy harvesting technology is seen as a way to extend the operating time of underwater equipment and reduce the frequency of battery recycling. However, most existing underwater equipment lacks the ability to simultaneously collect wireless energy and transmit and receive signals. Therefore, how to design underwater acoustic communication equipment with wireless energy harvesting capabilities and appropriate operating methods is a technical problem that needs to be solved.

[0003] Summary of the Invention

[0004] The purpose of the present invention is to solve the above-mentioned defects in the prior art and to provide an underwater acoustic communication device and method with wireless energy collection function.

[0005] The first object of the present invention can be achieved by adopting the following technical solutions:

[0006] An underwater acoustic communication device with a wireless energy collection function, comprising: a sensor, a data storage unit, a receiving transducer, a transmitting transducer, a duty circuit module, an energy collection module, an energy storage module, a receiving information processing module, a single-chip computer minimum system, a transmitting information processing module, a power amplifier module, an impedance matching circuit, and an interface. The receiving transducer and the transmitting transducer are hereinafter referred to as a hydrophone and a loudspeaker, respectively.

[0007] The sensor collects environmental data and outputs it to the single chip microcomputer minimum system;

[0008] The data storage unit is connected to the single chip microcomputer minimum system to store and exchange data;

[0009] The hydrophone collects external environmental signals and transmits them to the duty circuit module, which is connected to the single-chip microcomputer minimum system;

[0010] The duty circuit module receives the signal from the hydrophone, cooperates with the single-chip microcomputer minimum system to perform frequency judgment and channel selection on the signal, and outputs the signal to the energy collection module or the receiving information processing module;

[0011] The energy collection module receives the signal from the duty circuit module, rectifies and boosts the signal to obtain a high DC voltage, and outputs it to the energy storage module;

[0012] The energy storage module receives the high DC voltage from the energy collection module, stores electrical energy and is respectively connected to the sensor, the duty circuit module, the receiving information processing module, the single-chip computer minimum system, the sending information processing module and the power amplifier module to provide working voltage;

[0013] The receiving information processing module receives the signal from the duty circuit module, performs gain amplification and filtering on the signal, and then outputs it to the single-chip microcomputer minimum system;

[0014] The single-chip minimum system is connected to the sensor to receive environmental data; connected to the data storage unit to store and exchange data; connected to the duty circuit module to participate in signal frequency judgment and channel selection; receives signals from the receiving information processing module and performs demodulation, analog-to-digital conversion, and interprets the information; and connected to the sending information processing module;

[0015] The transmission information processing module receives the driving signal and the wake-up signal from the single-chip microcomputer minimum system, generates a specified transmission signal, and outputs it to the power amplifier module;

[0016] The power amplifier module receives the signal from the transmission information processing module, performs power amplification and filtering operations on the signal, and outputs it to the impedance matching circuit;

[0017] The impedance matching circuit receives the transmission signal from the power amplifier module, adjusts the impedance of the output end of the power amplifier module, eliminates the capacitive part, reduces the reactive power loss and achieves the best power transmission matching with the loudspeaker, and outputs it to the loudspeaker;

[0018] The loudspeaker is used to transmit signals into the external underwater acoustic environment;

[0019] The interface is used to download data stored in the data storage unit or to program the single chip microcomputer minimum system.

[0020] Furthermore, the duty circuit module includes a voltage comparator and a relay, wherein one end of the voltage comparator receives the signal from the hydrophone, and the other end adds a fixed voltage as a reference voltage. When the received signal voltage value is greater than the reference voltage value, the output is a high level, otherwise it is a low level, thereby realizing the conversion from sine wave to square wave, which facilitates the single-chip microcomputer minimum system to detect the signal frequency;

[0021] The MCU minimum system receives the signal from the voltage comparator and uses the timer's capture function to detect the number of square wave transitions within a certain period to determine the signal frequency. If the signal frequency is detected to be the target frequency, the MCU minimum system will send an enable signal to the relay and a wake-up signal to the receiving information processing module. If the signal frequency is detected to be inconsistent with the target frequency, the MCU minimum system will not send any signals to other modules.

[0022] The relay receives the signal from the hydrophone and the enable signal of the single-chip microcomputer minimum system. When the enable signal is received, the relay is energized and outputs the signal from the hydrophone to the receiving information processing module; when the enable signal is not received, the relay is released and outputs the signal from the hydrophone to the energy harvesting module.

[0023] The design of the duty circuit module enables the device to distinguish the types of signals received by the hydrophone by frequency, which is the key to the underwater acoustic communication equipment's ability to perform wireless energy collection.

[0024] Furthermore, the received information processing module includes an automatic gain amplifier circuit, a filter circuit and a voltage follower, wherein:

[0025] The automatic gain amplifier circuit receives the signal from the duty circuit module. The core chip in it can automatically adjust the gain according to the size of the control voltage, and form a linear relationship within a certain range. It limits the signal with a large voltage amplitude and amplifies the signal with a small voltage amplitude, so as to adjust the different amplitudes of the received signal to a fixed value, and output the signal to the filter circuit.

[0026] The filter circuit receives the signal from the automatic gain amplifier circuit and uses a bandpass filter to filter out noise interference from other frequency components, which is conducive to ensuring the system's effective signal processing and outputs the signal to the voltage follower;

[0027] The voltage follower receives the signal from the filter circuit. Based on an operational amplifier, the voltage follower adjusts matching resistors to ensure the output voltage amplitude is approximately equal to the input voltage amplitude. The voltage follower then outputs the signal to the microcontroller's minimum system. The voltage follower has high input impedance and low output impedance, making it suitable for use as a buffer or isolation circuit.

[0028] Furthermore, the energy collection module includes a rectifier circuit and a boost circuit, wherein:

[0029] The rectifier circuit receives signals from the duty circuit module. Since DC power, not AC power, is required to charge the energy storage medium, the rectifier circuit uses two diodes and a filter capacitor to convert AC power into DC power and output it to the boost circuit.

[0030] The boost circuit receives DC power from the rectifier circuit. At this point, the DC voltage is too low to charge the energy storage medium. Therefore, the boost circuit uses a chip to boost the low DC voltage to a high DC voltage suitable for charging the subsequent energy storage medium and outputs it to the energy storage module.

[0031] Furthermore, the energy storage module includes an energy storage medium and a voltage conversion circuit, wherein:

[0032] The energy storage medium usually uses a lithium battery. The DC power of a certain amplitude from the boost circuit can charge the lithium battery, and the lithium battery is connected to the input end of the transformer circuit.

[0033] The voltage conversion circuit receives energy from the energy storage medium. This includes circuits for converting 3.7V to 5V, +5V to -5V, and +5V to +3.3V, each implemented using three different chips. After voltage conversion, the signal is transmitted to the sensor, on-duty circuit module, receiving information processing module, single-chip microcomputer minimum system, transmitting information processing module, and power amplifier module, providing operating voltage for each module.

[0034] Furthermore, the transmission information processing module includes a signal generation submodule and a filtering submodule. The signal generation submodule receives the driving signal and data from the single-chip microcomputer minimum system, uses the DDS series chip to generate smooth, high-precision, high-resolution sine wave signals of different frequencies, and outputs the signal to the filtering submodule. In addition, the DDS series chip receives the wake-up signal from the single-chip microcomputer minimum system and enters the working state only after receiving the wake-up signal, thereby saving equipment energy consumption.

[0035] The filtering submodule receives the signal from the signal generating submodule, performs all-pass filtering on the signal, improves the frequency response of the signal, and outputs it to the power amplifier module.

[0036] Furthermore, the power amplifier module includes a preamplifier submodule, a power amplifier submodule and a low-pass filter submodule, wherein:

[0037] The preamplifier module includes a chip and peripheral circuits. It determines the amplification factor of the input signal by adjusting the resistance value in the peripheral circuits. Since the power amplifier module has certain requirements for the input signal amplitude, and the signal amplitude output by the signal generation module cannot be changed, the preamplifier module receives the signal from the filter module, amplifies the signal amplitude to a certain value, and outputs it to the power amplifier module.

[0038] The power amplifier module uses a Class D power amplifier. The Class D power amplifier includes the chip and its peripheral circuits. The self-oscillating circuit, bootstrap circuit, and feedback resistor adjustment determine the voltage gain of the power amplifier module. The power amplifier module receives the signal from the preamplifier module, amplifies the signal power, generates a PMW signal, and outputs it to the low-pass filter module.

[0039] The low-pass filtering submodule receives the PMW signal from the power amplifier submodule, reconstructs the signal into an analog signal through an LC low-pass filter, and outputs it to the impedance matching circuit.

[0040] Furthermore, the impedance matching circuit includes tuning matching and transformer matching, wherein,

[0041] The tuning and matching receives the signal from the low-pass filter module and uses the inductor to eliminate the capacitive part of the impedance at the input end of the amplifier, which can reduce the reactive power consumption of the equipment. After tuning and matching, the signal is output to the transformer for matching;

[0042] The transformer matching receives the signal from the tuned matching, adjusts the number of turns of the transformer coil according to the result of the power amplifier module, matches the output impedance of the power amplifier with the input impedance of the amplifier to achieve maximum power transmission, and the signal is output to the amplifier after transformer matching.

[0043] Another object of the present invention is achieved through the following technical solutions:

[0044] An underwater acoustic communication method based on an underwater acoustic communication device with a wireless energy harvesting function, the underwater acoustic communication method comprising:

[0045] Wireless energy harvesting and power supply steps:

[0046] S1, the hydrophone receives the underwater acoustic signal, converts the underwater acoustic signal into an electrical signal, and outputs it to the duty circuit module;

[0047] The voltage comparator in the duty circuit module, S2, converts the sine wave signal from the hydrophone into a square wave and outputs it to the microcontroller system. The system uses the capture function of its internal timer to determine the frequency. If the detected signal frequency is not the desired frequency, the microcontroller will not send the enable signal to the relay. The relay is now released, and the signal from the hydrophone enters the energy harvesting module through the relay.

[0048] S3. The energy collection module receives the electrical signal. The rectifier circuit first converts the electrical signal from AC to DC, and then outputs it to the boost circuit. The boost circuit boosts the low DC voltage to a high DC voltage and then outputs it to the energy storage module.

[0049] S4. The energy storage module receives the above-mentioned high DC voltage and stores it in the energy storage medium. The energy storage medium outputs the energy to the transformer circuit. The transformer circuit adjusts the voltage value to the operating voltage required by the sensor, duty circuit module, receiving information processing module, single-chip computer minimum system, sending information processing module, and power amplifier module, and outputs it to the above-mentioned modules to provide the operating voltage.

[0050] Receive signal processing steps:

[0051] R1, the hydrophone receives the underwater acoustic signal, converts the underwater acoustic signal into an electrical signal, and outputs it to the duty circuit module. The electrical signal is hereinafter referred to as the received signal;

[0052] The voltage comparator in R2 and the duty circuit module converts the received signal from the hydrophone into a square wave and outputs it to the single-chip microcomputer minimum system, which uses the capture function of its internal timer to determine the frequency. When it detects that the received signal frequency matches the given useful signal frequency, the single-chip microcomputer will send an enable signal to the relay and a wake-up signal to the receiving information processing module. After receiving the enable signal, the relay is in the energized state, and the core chip in the receiving information processing module will also enter the working state after receiving the wake-up signal. The received signal from the hydrophone will be output to the receiving information processing module via the relay;

[0053] The automatic gain amplifier circuit in the R3 and receiving information processing modules first stabilizes the received signals of varying amplitudes to a uniform value and outputs them to the filter circuit. The filter circuit uses bandpass filtering to remove as much noise as possible from other frequencies before outputting them to the voltage follower. The voltage follower's input impedance is approximately infinite, acting as a buffer and isolation device. The signal is then output to the microcontroller's minimum system.

[0054] R4, the single-chip microcomputer minimum system performs demodulation and analog-to-digital conversion operations on the received signal and reads the information carried in the received signal;

[0055] Steps for reporting abnormal data:

[0056] Y1. The sensor collects environmental data and outputs the data to the single-chip minimum system;

[0057] Y2. The single-chip microcomputer minimum system detects environmental data and stores the environmental data in the data storage unit through the interface. When abnormal data is detected, the single-chip microcomputer minimum system sends a wake-up signal to the transmission information processing module, causing its core chip to enter the working state and drive the signal generation submodule in the transmission information processing module to generate a modulation signal.

[0058] Y3, the signal generation submodule generates a modulated signal of a certain frequency, outputs it to the filtering submodule to remove high-frequency noise, and outputs it to the power amplifier module;

[0059] The preamplifier submodule in the power amplifier module receives the signal from the signal generation submodule, performs preliminary amplification on the signal amplitude and outputs it to the power amplifier submodule; the power amplifier submodule amplifies the signal amplitude by a certain multiple and outputs it to the low-pass filter submodule; the low-pass filter submodule reconstructs the signal into an analog signal and outputs it to the impedance matching circuit;

[0060] Y5. The tuning and matching in the impedance matching circuit is used to eliminate the capacitive part of the loudspeaker impedance, and the transformer is used to match the output impedance of the power amplifier with the input impedance of the loudspeaker. The power amplifier module outputs the signal to the impedance matching circuit to reduce reactive power consumption and achieve optimal power transmission matching with the loudspeaker. After passing through the impedance matching circuit, the signal is output to the loudspeaker.

[0061] Y6. The loudspeaker converts the received signal into an underwater acoustic signal and sends it to the target node to notify the occurrence of abnormal data.

[0062] The present invention has the following advantages and effects compared to the prior art:

[0063] 1. The present invention proposes an underwater acoustic communication device with wireless energy collection function. The device can collect various non-useful signals in the water and convert them into energy that can be used by the device. At the same time, it has the function of sending and receiving information and is suitable for long-term operation underwater.

[0064] 2. This invention proposes an underwater acoustic communication method based on this underwater acoustic communication device. At the receiving end, a duty circuit module classifies received signals, uses an energy harvesting module and an energy storage module to convert non-useful signals into electrical energy that can be used by the device's energy consumption module, and uses a received information processing module and a single-chip microcomputer minimum system to process useful signals. At the transmitting end, when a sensor detects abnormal data, it sends a signal to the target node to report the abnormality. This method achieves both wireless energy harvesting and information reception and transmission, making the device highly functional. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0066] FIG1 is a structural block diagram of an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0067] FIG2 is a working principle diagram of a duty circuit module in an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0068] FIG3 is a detailed structural block diagram of a receiving information processing module in an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0069] FIG4 is a detailed structural block diagram of an energy harvesting module in an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0070] FIG5 is a detailed structural block diagram of an energy storage module in an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0071] FIG6 is a flow chart of a working method of a receiving end in an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0072] 7 is a detailed structural block diagram of a sending information processing module in an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0073] FIG8 is a detailed structural block diagram of a power amplifier module in an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0074] 9 is a detailed structural block diagram of an impedance matching circuit module in an underwater acoustic communication device with wireless energy harvesting capability provided by an embodiment of the present invention;

[0075] FIG10 is a flow chart of a working method of a transmitter in an underwater acoustic communication device with wireless energy collection capability provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0076] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0077] Example 1

[0078] This embodiment 1 discloses an underwater acoustic communication device with a wireless energy harvesting function. The hydrophone used has a center frequency of 28 kHz and a frequency band of 27-29 kHz. 28 kHz is approximately set as the operating frequency of the entire communication system. The hydrophone collects external signals and is connected to a duty circuit module.

[0079] The duty circuit module receives the signal from the hydrophone, and works with the single-chip microcomputer minimum system to determine the frequency and select the channel of the signal, and outputs the signal to the energy collection module or the receiving information processing module;

[0080] The energy collection module receives the signal from the duty circuit module, rectifies and boosts the signal to obtain a high DC voltage, and outputs it to the energy storage module;

[0081] The energy storage module receives the high DC voltage from the energy collection module, stores the electric energy and is respectively connected to the sensor, the duty circuit module, the receiving information processing module, the single chip computer minimum system, the sending information processing module and the power amplifier module to provide the working voltage;

[0082] The receiving information processing module receives the signal from the duty circuit module, amplifies and filters the signal, and then outputs it to the single-chip microcomputer minimum system;

[0083] The single-chip microcomputer minimum system consists of a single-chip microcomputer, a crystal oscillator, a power supply circuit, a download circuit, and a reset circuit. The single-chip microcomputer is the mainstream STM32F103ZET6. The single-chip microcomputer minimum system connects to sensors to receive environmental data; connects to the data storage unit to store and exchange data; connects to the duty circuit module to participate in signal frequency determination and channel selection; receives signals from the receiving information processing module and performs demodulation, analog-to-digital conversion, and information interpretation; and connects to the transmitting information processing module.

[0084] The sending information processing module receives the driving signal and wake-up signal from the single-chip microcomputer minimum system, generates a specified sending signal, and outputs it to the power amplifier module;

[0085] The power amplifier module receives the signal from the transmission information processing module, performs power amplification and filtering operations on the signal, and outputs it to the impedance matching circuit;

[0086] The impedance matching circuit receives the transmission signal from the power amplifier module, adjusts the impedance of the transmission signal, eliminates the capacitive part, reduces the reactive power loss and achieves the best power transmission match with the loudspeaker, and outputs it to the loudspeaker;

[0087] The microphone is used to transmit signals into the external underwater acoustic environment.

[0088] In this embodiment, the duty circuit module includes a voltage comparator and a relay to receive signals from the hydrophone. The voltage comparator uses an LM393 chip to convert a sine wave into a square wave. The relay utilizes an optocoupler isolation relay, with a PC817 as the optocoupler, and a light-emitting diode to control the relay's engagement and release. The duty circuit module is connected to the microcontroller minimum system, working with it to determine the signal's frequency and select the channel, then outputting the signal to the energy harvesting module or the received signal processing module.

[0089] In this embodiment, the receiving information processing module includes an automatic gain amplifier circuit, a filter circuit, and a voltage follower. The automatic gain amplifier circuit utilizes a VCA810 chip and an INA828 instrumentation amplifier. The VCA810 chip receives signals from the duty circuit module at its input and automatically adjusts the signal gain based on the control voltage. The signal is then output to the INA828 instrumentation amplifier, achieving a fixed gain. The filter circuit utilizes an MFB structure and an active bandpass filter based on the RS722XK operational amplifier. The filter circuit receives the signal from the automatic gain amplifier circuit, filters out noise interference from other frequency components, and outputs the signal to the voltage follower. The voltage follower utilizes the RS721XM operational amplifier chip. Its input receives signals from the filter circuit, adjusts matching resistors to ensure that the output signal voltage amplitude is approximately equal to the input signal voltage amplitude, and then outputs the signal to the single-chip microcomputer minimum system.

[0090] In this embodiment, the energy harvesting module includes a rectifier circuit and a boost circuit. The rectifier circuit receives signals from the duty circuit. The rectifier circuit uses a voltage-doubling rectifier circuit based on the BAT54S chip to convert the input AC signal into a DC signal and increase the output voltage to twice the input voltage. The boost circuit, based on the BQ25504 chip, boosts the low DC voltage output by the voltage-doubling rectifier circuit to a high DC voltage, which is then output to the energy storage module for storage.

[0091] In this embodiment, the energy storage module includes an energy storage medium and a voltage conversion circuit. The energy storage medium receives signals from the energy harvesting module. The energy storage medium is a 3.7V lithium battery, with its output connected to the voltage conversion circuit. The voltage conversion circuit includes three circuits: +3.7V to +5V, +5V to -5V, and +5V to +3.3V. These circuits utilize the ME2188A50XG, ICL7660SCPAZ, and AMS1117-3.3 chips, respectively. The +3.7V to +5V output is connected to the device's sensors, voltage comparator, automatic gain amplifier circuit, filter circuit, voltage follower, signal generation submodule, and preamplifier submodule. The +5V to -5V output is connected to the device's voltage follower and preamplifier submodule, both of which are powered by a ±5V dual power supply. The +5V to +3.3V converter is connected to the microcontroller minimum system. The lithium battery outputs electrical energy, converted by the voltage conversion circuit, to power each of these modules.

[0092] In this embodiment, the sending information processing module includes a signal generating submodule and a filtering submodule. The signal generating submodule uses the DDS series chip AD9850. The single-chip microcomputer minimum system inputs the original data and the driving signal into the AD9850 chip and generates a smooth, high-precision, high-resolution sinusoidal wave signal of different frequencies, and outputs the signal to the filtering submodule; in addition, the AD9850 chip receives a wake-up signal from the single-chip microcomputer minimum system and enters the working state only after receiving the wake-up signal, saving equipment energy consumption; the filtering submodule uses an elliptical all-pass filter, receives the signal from the signal generating submodule and performs all-pass filtering on the signal, improves the frequency response of the signal, and outputs it to the power amplifier module.

[0093] In this embodiment, the power amplifier module includes a preamplifier submodule, a power amplifier submodule, and a low-pass filter submodule. The preamplifier submodule uses an OP1177ARZ chip, receives signals from the transmission information processing module, determines the amplification factor of the input signal by adjusting the resistance value in the peripheral circuit, and outputs it to the power amplifier submodule. The power amplifier module uses an IRS2092S chip, which integrates a PMW modulator and chip protection, two external MOSFETs, and a small number of peripheral devices. It receives the signal from the preamplifier submodule, amplifies it, and converts it into a PMW signal, which is output to the low-pass filter submodule. The low-pass filter submodule uses an LC low-pass filter to reconstruct the PMW signal into an analog signal and output it to the impedance matching circuit.

[0094] In this embodiment, the impedance matching circuit includes tuned matching and transformer matching. The tuned matching uses a series inductor structure to eliminate the capacitive portion of the loudspeaker input. The signal from the power amplifier module is input to the transformer matching after being tuned and matched. The transformer core in the transformer matching uses the EE65 type. The number of coil turns is adjusted according to the output impedance of the power amplifier module and the input impedance of the loudspeaker. The signal is input to the loudspeaker after being matched by the transformer.

[0095] Example 2

[0096] Based on the underwater acoustic communication device with a wireless energy harvesting function disclosed in the above embodiment 1, this embodiment further discloses an underwater acoustic communication method based on the underwater acoustic communication device with a wireless energy harvesting function, the underwater acoustic communication method comprising:

[0097] Wireless energy harvesting and power supply steps:

[0098] S1, a hydrophone with a center frequency of 28kHz receives the underwater acoustic signal, converts the underwater acoustic signal into an electrical signal, and outputs the electrical signal to the duty circuit module;

[0099] The voltage comparator in the S2 duty circuit module converts the sine wave signal from the hydrophone into a square wave and outputs it to the microcontroller system, which uses the capture function of its internal timer to determine the frequency. The inter-device signal communication frequency is set to 28kHz. If the electrical signal frequency is not 28kHz, the microcontroller system will not send the enable signal to the relay. The relay remains released, and the electrical signal from the hydrophone enters the energy harvesting module through the relay.

[0100] S3. The energy collection module receives the electrical signal. The rectifier circuit first converts the electrical signal from AC to DC, and makes the output voltage twice the input voltage. The signal is then output to the boost circuit. The boost circuit boosts the low DC voltage to a high DC voltage that can charge the lithium battery, and then outputs the DC voltage to the energy storage module.

[0101] S4. The energy storage module receives the above-mentioned high DC voltage and stores it in the energy storage medium lithium battery. The lithium battery outputs a signal with an amplitude of 3.7V to the voltage conversion circuit. After the +3.7V to +5V circuit, it powers the sensor, voltage comparator, automatic gain amplifier circuit, filter circuit, voltage follower, signal generation submodule, and preamplifier submodule in the device; after the +3.7V to +5V circuit and +5V to -5V circuit, it powers the voltage follower and preamplifier submodule in the device that require dual power supply; after the +5V to +3.3V circuit, it powers the minimum system of the microcontroller.

[0102] To fully demonstrate the effectiveness of the wireless energy harvesting function, a key technology in this invention, an experiment was conducted to verify the wireless energy harvesting capability. The experimental setup is as follows:

[0103] The energy transmitter sends a signal at a frequency of f = 27kHz to the device at different power levels, with the distance between them being d = 100m. Assuming a spreading factor s = 1.5 and a directivity coefficient DI of 10dB, the propagation loss formula is used to calculate the received signal sound pressure level (SPL) at the device and the measured power collected by the device as follows:

[0104] Table 1. Information parameters of energy transmitter and device receiver

[0105] Receive signal processing steps:

[0106] R1, a hydrophone with a center frequency of 28kHz receives the underwater acoustic signal, converts the underwater acoustic signal into an electrical signal, and outputs the electrical signal to the duty circuit module. The electrical signal is hereinafter referred to as the received signal;

[0107] The voltage comparator in R2 and the duty circuit module converts the sinusoidal signal from the hydrophone into a square wave and outputs it to the microcontroller system, where it uses the capture function of its internal timer to determine the frequency. When the received signal frequency is detected to be 28kHz, the microcontroller sends an enable signal to the relay and a wake-up signal to the receiving information processing module. Upon receiving the enable signal, the relay is energized, and the VCA810 chip in the receiving information processing module enters operation upon receiving the wake-up signal. The received signal from the hydrophone is output to the receiving information processing module via the relay.

[0108] The automatic gain amplifier circuit in the R3 receiving information processing module first stably amplifies the received signals of varying amplitudes to a uniform amplitude, set at 2V in this embodiment, and outputs it to the filter circuit. The filter circuit uses an active second-order Butterworth bandpass filter to remove confounding frequency signals and appropriately amplify the received signal before outputting it to a voltage follower. The voltage follower's input impedance is approximately infinite, acting as a buffer and isolation device, maintaining the received signal amplitude constant before outputting it to the single-chip microcomputer minimum system.

[0109] R4, the single-chip microcomputer minimum system performs demodulation and analog-to-digital conversion operations on the received signal and reads the information carried in the received signal;

[0110] Steps for reporting abnormal data:

[0111] Y1. The sensor collects environmental data and outputs the data to the single-chip minimum system;

[0112] Y2. The single-chip microcomputer minimum system detects environmental data and stores the environmental data in the data storage unit through the interface. When abnormal data is detected, the single-chip microcomputer minimum system sends a wake-up signal to the information processing module. The AD9850 chip in the signal generation submodule enters the working state after receiving the wake-up signal.

[0113] Y3, the signal generation submodule generates a modulated signal of a certain frequency, outputs it to the filtering submodule to remove high-frequency noise, and outputs it to the power amplifier module;

[0114] The preamplifier submodule in the power amplifier module receives the signal from the signal generation submodule, performs preliminary amplification on the signal amplitude and outputs it to the power amplifier submodule; the power amplifier submodule amplifies the signal amplitude by a certain multiple and outputs it to the low-pass filter submodule; the low-pass filter submodule reconstructs the signal into an analog signal and outputs it to the impedance matching circuit;

[0115] Y5. The tuning and matching in the impedance matching circuit is used to eliminate the capacitive part of the loudspeaker impedance, and the transformer is used to match the output impedance of the power amplifier with the input impedance of the loudspeaker. The power amplifier module outputs the signal to the impedance matching circuit to reduce reactive power consumption and achieve optimal power transmission matching with the loudspeaker. After passing through the impedance matching circuit, the signal is output to the loudspeaker.

[0116] Y6. The loudspeaker converts the received signal into an underwater acoustic signal and sends it to the target node to notify the occurrence of abnormal data.

[0117] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. An underwater acoustic communication device with wireless energy collection function, characterized in that: The underwater acoustic communication equipment includes: a sensor, a data storage unit, a receiving transducer, a transmitting transducer, a duty circuit module, an energy collection module, an energy storage module, a receiving information processing module, a single-chip minimum system, a transmitting information processing module, a power amplifier module, an impedance matching circuit and an interface. The receiving transducer and the transmitting transducer are referred to as a hydrophone and a loudspeaker, respectively. The sensor collects environmental data and outputs it to the single-chip microcomputer minimum system; The data storage unit is connected to the single-chip microcomputer minimum system to store and exchange data; The hydrophone collects external environmental signals and transmits them to the duty circuit module, and the duty circuit module is connected to the single-chip microcomputer minimum system; The duty circuit module receives the signal from the hydrophone, performs frequency judgment and channel selection on the signal in cooperation with the single-chip minimum system, and outputs the signal to the energy collection module or the receiving information processing module; The energy collection module receives the signal from the duty circuit module, rectifies and boosts the signal to obtain a high DC voltage, and outputs it to the energy storage module; The energy storage module receives the high DC voltage from the energy collection module, stores electric energy and is respectively connected to the sensor, the duty circuit module, the receiving information processing module, the single-chip minimum system, the sending information processing module and the power amplifier module to provide working voltage; The receiving information processing module receives the signal from the duty circuit module, performs gain amplification and filtering on the signal, and then outputs it to the single-chip microcomputer minimum system; The single-chip minimum system is connected to the sensor to receive environmental data; connected to the data storage unit to store and exchange data; connected to the duty circuit module to participate in the frequency judgment and channel selection of the signal; receives the signal from the receiving information processing module and performs demodulation, analog-to-digital conversion, and interprets the information; and connected to the sending information processing module; The transmission information processing module receives the driving signal and the wake-up signal from the single-chip minimum system, generates a specified transmission signal, and outputs it to the power amplifier module; The power amplifier module receives the signal from the transmission information processing module, performs power amplification and filtering operations on the signal, and outputs it to the impedance matching circuit; The impedance matching circuit receives the transmission signal from the power amplifier module, adjusts the impedance of the output end of the power amplifier module, eliminates the capacitive part, reduces the reactive power loss and achieves the best power transmission match with the loudspeaker, and outputs it to the loudspeaker; The loudspeaker is used to transmit signals into the external underwater acoustic environment; The interface is used to download data stored in the data storage unit or to program the single-chip microcomputer minimum system.

2. The underwater acoustic communication device with wireless energy collection function according to claim 1, characterized in that: The duty circuit module includes a voltage comparator and a relay, wherein: The voltage comparator receives the signal from the hydrophone and converts it into a square wave and transmits it to the microcontroller minimum system; The single-chip minimum system receives the signal from the voltage comparator, determines the signal frequency, and determines whether to transmit the enable signal to the relay based on the result; The relay receives the signal from the hydrophone and the enable signal of the microcontroller minimum system. When the enable signal is received, the relay is energized and outputs the signal from the hydrophone to the receiving information processing module; when the enable signal is not received, the relay is released and outputs the signal from the hydrophone to the energy collection module.

3. The underwater acoustic communication device with wireless energy collection function according to claim 2, characterized in that: The receiving information processing module includes an automatic gain amplifier circuit, a filter circuit and a voltage follower, wherein: The automatic gain amplifier circuit receives the signal from the duty circuit module, amplifies the output amplitude of the signal to a fixed value, and outputs it to the filter circuit; The filter circuit receives the signal from the automatic gain amplifier circuit, filters out the interference frequency component in the signal, and outputs it to the voltage follower; The voltage follower receives the signal from the filter circuit, acts as a buffer circuit to maintain the signal amplitude, and outputs it to the microcontroller minimum system.

4. The underwater acoustic communication device with wireless energy collection function according to claim 3 is characterized in that: The energy collection module includes a rectifier circuit and a boost circuit, wherein: The rectifier circuit receives the signal from the duty circuit module, converts the AC power into DC power, and outputs it to the boost circuit; The boost circuit receives the DC power from the rectifier circuit, boosts the low DC voltage to a high DC voltage, and outputs it to the energy storage module.

5. The underwater acoustic communication device with wireless energy collection function according to claim 4, characterized in that: The energy storage module includes an energy storage medium and a voltage conversion circuit, wherein: The energy storage medium receives energy from the boost circuit for storage and can output it to the voltage conversion circuit; The transformer circuit receives energy from the energy storage medium and transmits it to the sensor, duty circuit module, receiving information processing module, single-chip minimum system, sending information processing module and power amplifier module after transformer, providing working voltage for each module.

6. The underwater acoustic communication device with wireless energy collection function according to claim 5, characterized in that: The sending information processing module includes a signal generation submodule and a filtering submodule, wherein: The signal generation submodule receives the driving signal and data from the single-chip microcomputer minimum system, modulates the data and outputs it to the filtering submodule; The filtering submodule receives the signal from the signal generating submodule, filters the signal and outputs it to the power amplifier module.

7. The underwater acoustic communication device with wireless energy collection function according to claim 6, characterized in that: The power amplifier module includes a preamplifier module, a power amplifier module and a low-pass filter module, wherein: The preamplifier module receives the signal from the filter module, adjusts the signal amplitude to a certain range, and outputs it to the power amplifier module; The power amplifier module receives the signal from the preamplifier module, amplifies the signal power, and outputs it to the low-pass filter module; The low-pass filter submodule receives the signal from the power amplifier submodule, filters the signal, and outputs it to the impedance matching circuit.

8. The underwater acoustic communication device with wireless energy collection function according to claim 7, characterized in that: The impedance matching circuit includes tuning matching and transformer matching, wherein: The tuning and matching receives the signal from the low-pass filter submodule, eliminates the capacitive part of the impedance at the input end of the loudspeaker, and outputs the signal to the transformer matching connection; The transformer matching receives the signal from the tuned matching, matches the output impedance of the tuned matching with the input impedance of the loudspeaker to achieve maximum power transmission, and outputs it to the loudspeaker.

9. An underwater acoustic communication method based on the underwater acoustic communication device with wireless energy collection function according to any one of claims 1 to 8, characterized in that The underwater acoustic communication method comprises: Wireless energy collection and power supply steps: S1, the hydrophone receives the water acoustic signal, converts the water acoustic signal into an electrical signal, and outputs it to the duty circuit module; S2. The voltage comparator in the duty circuit module converts the electrical signal from the hydrophone into a square wave and outputs it to the single-chip microcomputer minimum system. The capture function of the timer is used to judge the frequency. When it is detected that the frequency of the electrical signal is not the frequency of the given useful signal, the microcontroller will not send an enable signal to the relay. The relay is in a released state at this time, and the electrical signal from the hydrophone will enter the energy collection module through the relay; S3, the energy collection module receives the above electrical signal, the rectifier circuit first converts the electrical signal from AC to DC, and then outputs it to the boost circuit, the boost circuit boosts the low DC voltage to a high DC voltage, and then outputs it to the energy storage module; S4, the energy storage module receives the above high DC voltage and stores it in the energy storage medium, the energy storage medium outputs the energy to the voltage conversion circuit, the voltage conversion circuit adjusts the voltage value to the working voltage required by the sensor, the duty circuit module, the receiving information processing module, the single-chip minimum system, the sending information processing module, and the power amplifier module, and outputs it to the above modules to provide the working voltage; Receive signal processing steps: R1, the hydrophone receives the water acoustic signal, converts the water acoustic signal into an electrical signal, and outputs it to the duty circuit module. The electrical signal is hereinafter referred to as the receiving signal; R2, the voltage comparator in the duty circuit module converts the receiving signal from the hydrophone into a square wave, outputs it to the single-chip microcomputer minimum system, and uses the capture function of its internal timer to make frequency judgments. When it is detected that the receiving signal frequency matches the given useful signal frequency, the single-chip microcomputer will send an enable signal to the relay and send a wake-up signal to the receiving information processing module. After receiving the enable signal, the relay is in the energized state, and the core chip in the receiving information processing module will also enter the working state after receiving the wake-up signal. The receiving signal from the hydrophone will be output to the receiving information processing module via the relay; R3, the automatic gain amplifier circuit in the receiving information processing module first stably amplifies the received signals of different amplitudes to the same amplitude and outputs them to the filter circuit. The filter circuit uses bandpass filtering to filter out the noise of other frequencies as much as possible, and then outputs them to the voltage follower. The input impedance of the voltage follower is approximately infinite, which plays a buffering and isolating role, and then outputs them to the minimum system of the single-chip microcomputer; R4, the single-chip microcomputer minimum system performs demodulation and analog-to-digital conversion operations on the received signal and reads the information carried in the received signal; Steps for reporting abnormal data: Y1. The sensor collects environmental data and outputs the data to the single-chip minimum system; Y2. The single-chip microcomputer minimum system detects the environmental data and stores the environmental data in the data storage unit through the interface; when abnormal data is detected, the single-chip microcomputer minimum system sends a wake-up signal to the sending information processing module to put its core chip into working state and drive the signal generation submodule in the sending information processing module to generate a modulation signal; Y3, the signal generation submodule generates a modulated signal of a certain frequency, outputs it to the filtering submodule, removes high-frequency noise, and outputs it to the power amplifier module; Y4, the preamplifier submodule in the power amplifier module receives the signal from the signal generation submodule, preliminarily amplifies the signal amplitude and outputs it to the power amplifier submodule; the power amplifier submodule amplifies the signal amplitude by a certain multiple and outputs it to the low-pass filter submodule; the low-pass filter submodule reconstructs the signal into an analog signal and outputs it to the impedance matching circuit; Y5. The tuning match in the impedance matching circuit is used to eliminate the capacitive part of the loudspeaker impedance, and the transformer matching adjusts the resistance value. The power amplifier module outputs the signal to the impedance matching circuit to achieve the best power transmission match with the loudspeaker and outputs the signal to the loudspeaker; Y6. The loudspeaker converts the above signal into an underwater acoustic signal and sends it to the target node to notify the occurrence of abnormal data.

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