CN120352857B - Shipborne transceiver for underwater acoustic positioning system and underwater acoustic positioning system - Google Patents

Abstract

The present invention discloses a shipboard transceiver and a hydroacoustic positioning system for use in a hydroacoustic positioning system, and relates to the field of marine oil exploration. The shipboard transceiver comprises a processing unit, a receiving unit, a transmitting unit, and a transceiver device. The processing unit comprises a processor and its peripheral circuits. The receiving unit comprises a function selection module, a receiver, a frequency selection module, and an analog-to-digital conversion circuit. The function selection module is used to change the working environment of the shipboard transceiver and receive transponder signals through the transceiver device. The frequency selection module is used to perform frequency selection processing on the received signal when the received signal is a narrowband signal. The transmitting unit is used to drive the transceiver device to transmit signals. The transceiver device comprises a wireless coil for use in an above-water environment and a transducer for use in an underwater environment. The present invention utilizes electromagnetic induction and hydroacoustic communication methods and corresponding hardware circuits to enable the shipboard transceiver to effectively meet the interaction requirements with the transponder in various usage scenarios.

Description

Shipborne transceiver for underwater acoustic positioning system and underwater acoustic positioning system

Technical Field

The invention relates to the field of offshore oil exploration, in particular to a ship-borne transceiver used in a hydroacoustic positioning system and the hydroacoustic positioning system.

Background

In existing offshore oil exploration technology, the onboard transceivers are typically mounted on exploration vessels, drilling platforms, etc., primarily to provide ranging and positioning functions, while the transponders are typically deployed as responsive ends at fixed points on the seafloor or on objects to be positioned. The on-board transceiver transmits a specific coded acoustic pulse signal, and after the transponder receives the signal from the on-board transceiver, a specific acoustic response signal is transmitted as a response signal, and the on-board transceiver calculates the distance between the on-board transceiver and the transponder, the position of the transponder and the like according to the time interval from the self-transmission of the signal to the receiving of the response signal and the like, so that the ranging and positioning functions are realized. In practical applications, the on-board transceiver and the transponder need to interact with each other in different use scenarios, such as in an on-water environment and in an underwater environment. However, existing interaction means of the on-board transceiver and the transponder are difficult to meet in different usage scenarios.

Disclosure of Invention

The present invention has been made in view of the above problems, and aims to provide an on-board transceiver for use in an underwater sound positioning system and an underwater sound positioning system which overcome or at least partially solve the above problems.

According to an aspect of an embodiment of the present application, there is provided a shipboard transceiver for use in an underwater sound location system, the shipboard transceiver including a processing unit, a receiving unit, a transmitting unit, and a transceiving device;

the processing unit comprises a processor and a peripheral circuit of the processor, wherein the processor is used for converting analog signals and digital signals, and the peripheral circuit comprises an operation panel circuit, a power supply circuit, a battery electric quantity detection circuit and a battery charging protection circuit;

the receiving unit comprises a function selecting module, a receiver, a frequency selecting module and an analog-digital conversion circuit, wherein the function selecting module is used for changing the working environment of the shipborne transceiver and receiving signals of the transponder through the transceiver;

The transmitting unit is used for driving the transceiver to transmit signals so as to communicate with the transponder;

the transceiver device includes a wireless coil for use in an aquatic environment and a transducer for use in an underwater environment.

Further, the operation panel circuit includes a button control circuit, a display screen control circuit, and a buzzer driving circuit;

The button control circuit comprises a knob matrix circuit and a debounce reset switch circuit;

The display screen control circuit is used for driving the display to enable the display to display real-time state information of the shipborne transceiver;

The buzzer driving circuit is used for driving the buzzer to sound when the on-board transceiver successfully receives the feedback of the transponder after sending the instruction.

Further, the receiver comprises a signal filtering and amplifying circuit and a signal shaping circuit;

the signal filtering and amplifying circuit comprises a differential amplifying circuit and a fourth-order Butterworth filter;

the signal shaping circuit converts the sine wave into a corresponding square wave using a voltage comparator.

Further, the frequency selection module comprises a narrow band pass filter constructed by a plurality of groups of capacitors and inductors.

Further, the transmitting unit comprises a wireless coil communication circuit, a transducer communication circuit and a digital-to-analog conversion circuit;

The wireless coil communication circuit comprises a linear power amplifier circuit and a filter, wherein the linear power amplifier circuit is used for driving the wireless coil to transmit signals;

the transducer communication circuit comprises a class D power amplifier circuit and a transmitting driving circuit, wherein the class D power amplifier circuit is used for driving a transducer to transmit signals, and the transmitting driving circuit is used for carrying out current enhancement and dead zone processing on the transmitted signals.

Further, the processor is connected with the output end of the frequency selection module, and detects whether a narrowband signal arrives or not through the level state of the GPIO interface.

According to another aspect of an embodiment of the present application, there is provided an underwater sound positioning system, which is characterized by comprising an instruction protocol design module, a signal processing module, and an onboard transceiver for use in an underwater sound positioning system as described above;

The instruction protocol design module is used for carrying out protocol design on a downlink instruction of the shipborne transceiver to the transponder and an uplink instruction of the transponder to the shipborne transceiver, wherein a plurality of groups of transponders are divided, a plurality of channels are divided for each group of transponders, and a plurality of transponder combinations are formed;

The signal processing module is used for performing signal processing on the received signal by adopting a preset algorithm.

Further, the downlink instruction comprises an inquiry instruction, an address coding instruction, an electric quantity detection instruction and a ranging instruction;

the instruction protocol design module is further to:

Aiming at an inquiry instruction, forward rotation pulses with a first preset frequency are used as guide codes, a plurality of frequency combinations are formed by combining a plurality of frequencies in pairs to be used as information codes, and the plurality of frequency combinations are combined with a plurality of time division strategies to obtain a plurality of different frequency division time division combinations;

Aiming at the address coding instruction, a binary frequency shift keying modulation mode is adopted, each code element is distributed to one of two preset different frequencies according to the value of the code element, and the address coding instruction is set to comprise a guide code, an information code and a check code;

aiming at the electric quantity detection instruction, taking forward rotation pulses with a first preset frequency as a guide code, and setting information codes by utilizing different frequencies so as to enable the electric quantity detection instruction to be different from an inquiry instruction;

For a ranging instruction, forward rotation pulses with a first preset frequency are used as a guide code, multiple frequencies are combined to form multiple frequency combinations by two-by-two to be used as an information code, the multiple frequency combinations are combined with multiple time division strategies to obtain multiple different frequency-division time-division combinations, and signal processing and delay measurement processing are performed.

Further, the uplink instruction comprises a response instruction and an electric quantity detection uplink instruction, wherein the response instruction comprises a narrowband signal response instruction and a broadband signal response instruction, and the broadband signal response instruction comprises a broadband linear frequency modulation signal response instruction and a broadband spread spectrum signal response instruction;

the instruction protocol design module is further to:

Aiming at the narrowband signal response instruction, taking the forward rotation pulse as a response signal, taking a signal with a second preset frequency as a guide code, combining the signals into a plurality of frequency combinations by utilizing a plurality of frequencies to form a plurality of response channels, and setting the total length of the narrowband signal response instruction;

aiming at a broadband linear frequency modulation signal response instruction, adopting a plurality of frequencies as center frequencies, and setting the bandwidth and duration of signals of each frequency;

Aiming at the broadband spread spectrum signal response instruction, a pseudo random sequence is used as the broadband spread spectrum signal response instruction of the transponder;

Aiming at the electric quantity detection uplink instruction, the forward rotation pulse with the second preset frequency is used as a guide code, the electric quantity of the transponder is represented by the information code with the preset number of bits, wherein each code element adopts a binary frequency shift keying modulation mode, and a check code is set.

Further, the signal processing module is further configured to:

And resolving the broadband signal by adopting a frequency domain fast correlation method, and detecting the broadband signal by adopting a spread spectrum signal identification method based on code division multiple access.

According to the technical scheme provided by the invention, two kinds of receiving and transmitting equipment of a wireless coil and a transducer are respectively designed according to different using requirements of a transponder deck and underwater, through electromagnetic induction, underwater sound communication modes and corresponding hardware circuits, the shipborne transceiver can well meet the interaction requirements of the transponder under various using occasions, the shipborne transceiver adopts a frequency selecting module to conveniently finish detection of narrowband signals, the processor is connected with the output end of the frequency selecting module, the level state of a GPIO interface is used for detecting whether narrowband signals arrive or not, in the detection process, the processor only needs to use a timer to determine the arrival time of each forward pulse, a complex software processing algorithm is not needed, so that the power consumption of the whole machine is effectively reduced, the design of an instruction protocol of the shipborne transceiver for down instructions is conveniently finished by combining time division and frequency division technologies, the inquiry instructions are conveniently combined with various different time division strategies, different inquiry codes are defined for a plurality of groups of transponders, the address coding instructions adopt a two-frequency shift keying modulation mode, the pilot codes, the information and the information code and the combination are effectively improved, the correlation rate of each transponder is greatly reduced, the relevant frequency channel is not occupied by the relevant code and the relevant frequency channel is greatly reduced, the relevant channel is not required to be simultaneously calculated, the relevant frequency channel sequence is not required to be completely and the relevant signal is not required to be completely processed, and the relevant frequency channel sequence is not required to be simultaneously and the relevant to be completely and the relevant to the signal sequence is only has the relevant frequency channel and the relevant frequency channel is reduced, but the relevant frequency channel is not required to the relevant frequency channel and the signal. In order to overcome the problems of multipath effect, sound wave attenuation and the like existing in the underwater sound signal during propagation, the shipborne transceiver can effectively improve the ranging precision and the anti-interference performance of communication of the shipborne transceiver through the hardware circuits of a transmitting unit and a receiving unit and the detection algorithm design of broadband signals and narrowband signals.

The foregoing description is only an overview of the present invention, and is intended to be implemented in accordance with the teachings of the present invention in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present invention more readily apparent.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:

FIG. 1 shows a block diagram of an on-board transceiver for use in an underwater sound location system according to one embodiment of the present application;

FIG. 2 shows a schematic diagram of a knob matrix circuit;

FIG. 3 shows a schematic diagram of a debounce reset switch circuit;

FIG. 4 shows a schematic diagram of a display screen control circuit;

Fig. 5 shows a schematic diagram of a buzzer driving circuit;

FIG. 6 shows a schematic diagram of the overall power architecture of the on-board transceiver;

FIG. 7 shows a schematic diagram of a power supply circuit;

FIG. 8 shows a schematic diagram of a battery charge detection circuit;

fig. 9 shows a schematic diagram of a battery charge protection circuit;

fig. 10 shows a block diagram of the structure of the receiving unit;

fig. 11 shows a schematic diagram of a fourth order butterworth filter;

FIG. 12 shows a schematic diagram of a signal shaping circuit;

Fig. 13 shows a schematic diagram of a frequency selection module;

fig. 14 shows a structural diagram of a wireless coil;

fig. 15 shows a block diagram of the structure of the transmitting unit;

FIG. 16 shows a schematic diagram of an LM386 minimum gain circuit;

FIG. 17 shows a schematic diagram of an emission drive circuit;

FIG. 18 shows a timing diagram of an anti-dead band waveform;

FIG. 19 shows a software design framework diagram of an underwater sound location system;

FIG. 20 illustrates a schematic diagram of an interrogation instruction;

FIG. 21 illustrates a schematic diagram of an address encoding instruction;

FIG. 22 is a schematic diagram of a power detection command;

FIG. 23 shows a schematic diagram of a narrowband signal reply instruction;

FIG. 24 is a schematic flow chart of narrowband signal detection;

FIG. 25 shows a schematic diagram one of frequency domain fast correlation;

FIG. 26 shows a second schematic diagram of frequency domain fast correlation;

FIG. 27 shows a schematic diagram of a mathematical model of a spread spectrum communication transmitter system;

fig. 28 shows a schematic flow chart of the ranging function;

FIG. 29 is a flow chart of an address encoding function;

FIG. 30 is a schematic flow chart of the power detection function;

Fig. 31 shows a schematic flow chart of the on-board transceiver power self-test function.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

Fig. 1 shows a block diagram of a ship-borne transceiver for use in an underwater sound location system according to an embodiment of the present application, which includes a processing unit 110, a receiving unit 120, a transmitting unit 130, and a transceiving apparatus 140, as shown in fig. 1.

The processing unit 110 includes a processor 1101 and peripheral circuits of the processor 1101. The processor 1101 is used for conversion of analog signals and digital signals. In practical applications, the processor 1101 may be a NUCLEO-U575ZI development board based on an STM32U575 microcontroller, and the STM32U575 microcontroller may be built with a 14-bit ADC module and a DAC module, which may be used for converting analog signals and digital signals. The peripheral circuits include an operation panel circuit (not shown in the figure), a power supply circuit 1102, a battery power detection circuit 1103, and a battery charge protection circuit 1104.

For the button configuration aspect of the operation panel, a plurality of multi-channel knobs and a plurality of self-resetting switch buttons can be selected as the control buttons 1105, for example, 4 10-channel knobs and 3 self-resetting switch buttons, and for the aspect of the display 1106, a DDM4 liquid crystal display can be selected. The operation panel is also provided with an active buzzer as feedback means for providing audio feedback. The operation panel circuit includes a button control circuit, a display screen control circuit, and a buzzer driving circuit. The button control circuit comprises a knob matrix circuit and a debounce reset switch circuit. A schematic of the knob matrix circuit is shown in fig. 2. The shipborne transceiver is also controlled by 3 self-resetting switch buttons, and a hardware debounce chip MAX6816 can be adopted for button signal processing, and a schematic diagram of the debounce reset switch circuit is shown in FIG. 3. The display screen control circuit is used for driving the display to enable the display to display real-time state information of the shipboard transceiver, such as key parameters of signal intensity, working frequency and the like. A schematic diagram of the display screen control circuit is shown in fig. 4. The buzzer driving circuit is used for driving the buzzer to sound when the on-board transceiver successfully receives the feedback of the transponder after sending the instruction. When the on-board transceiver successfully receives the feedback of the transponder after sending the instruction, the buzzer is driven by the buzzer driving circuit to make clear sound, and visual hearing confirmation is provided for the operation result. A schematic diagram of the buzzer driving circuit is shown in fig. 5.

Aiming at the requirements of multiple functions, the shipborne transceiver uses a convenient operation panel, provides visual operation guidance and clear information display, and reduces operation steps. The panel has the function of displaying input and output results, and can input information in the form of buttons or knobs, so that operators can be effectively ensured to easily perform equipment configuration, state monitoring and data query. An operator can select the operating mode of the shipboard transceiver using the knob and button and view the resulting information via the display.

Considering that the overall power consumption of the underwater sound positioning system does not exceed 50mA, and that other circuits of the underwater sound positioning system except the processor 1101 are all powered by 5V, the power circuit 1102 can be a DC-DC (direct current-direct current) conversion chip of TPS 54331. Fig. 6 shows a schematic diagram of the overall power architecture of the shipboard transceiver, which clearly shows the various links and components of the power management, wherein the battery voltage VBAT is 12.6V, the power supply of the power circuit is 5V, and the power supply of the processor includes 3.3V and 1.8V. Fig. 7 shows a schematic diagram of a power supply circuit, as shown in fig. 7, the output voltage of which is externally adjustable, the voltage divider network being composed of R _O1 and R _O2. The formula (1) and the formula (2) are output voltage relations. The output voltage was set to 5V, using R _O1=10.2kΩ,R_O2 =1.91 kΩ.

Formula (1)

Formula (2)

Wherein, R _O1 and R _O2 are two resistors in the voltage divider network, V _ref is the reference voltage, and V _OUT is the output voltage.

The minimum value of the output inductance is calculated in the power supply circuit from equation (3). The current ripple rate K _IND =0.3 is selected, the minimum inductance value obtained through calculation is 5.7 muh, and finally the inductance of 6.8 muh is selected.

Formula (3)

Wherein, L _MIN is the minimum inductance value, V _OUT(MAX) is the maximum value of the output voltage, V _IN(MAX) is the maximum value of the input voltage, V _OUT is the output voltage, K _IND is the current ripple rate, I _OUT is the output current, and f _SW is the switching frequency of the power chip.

The minimum capacitance value can be calculated from equation (4).

Formula (4)

Wherein C _O(MIN) is the minimum capacitance, R _O is the output load impedance (V _O/I_O）,F_CO(MAX) is the required crossover frequency, so C _O can be a ceramic capacitor with 33 muF capacitance, and two capacitors with 66 muF composition are used.

The battery power detection circuit 1103 is configured to detect a power of the battery 1107, where the battery power detection circuit 1103 may use an LTC4151 chip and communicate with the processor 1101 through an I ² C bus interface. A schematic diagram of the battery level detection circuit 1103 is shown in fig. 8.

For the battery 1107, 3 series-8 parallel 18650 lithium batteries are selected as power sources, the total voltage of the batteries is increased to 12.6V by the series connection of the batteries, and the total capacitance is increased to 35200mAh by the parallel connection. The battery charge protection circuit 1104 may protect the charge and discharge of the battery 1107 using a DW01B chip, which is used for single battery overcharge and overdischarge protection. A schematic diagram of the battery charge protection circuit 1104 is shown in fig. 9, and three DW01B chips may be used to provide protection for 3 lithium batteries 18650 connected in series.

The receiving unit 120 of the on-board transceiver is configured to perform preprocessing such as amplifying, filtering, etc. on a received signal (e.g., an analog signal), and fig. 10 shows a block diagram of the receiving unit, and as shown in fig. 10, the receiving unit 120 includes a function selecting module 1201, a receiver 1202, a frequency selecting module 1203, and an analog-to-digital conversion circuit 1204 (i.e., an a/D circuit). The transceiver device 140 includes a wireless coil 1401 for use in an aquatic environment and a transducer 1402 for use in an underwater environment. The function selection module 1201 is used to modify the operating environment of the on-board transceiver to receive signals from the transponder via the transceiver device 140. The receiver 1202 is configured to pre-process a received signal, and then select to send the received signal to the frequency selection module 1203 or the analog-digital conversion circuit 1204 according to a signal form, where when the received signal is a narrowband signal, the received signal is sent to the frequency selection module 1203 to be processed, and when the received signal is a wideband signal, the received signal is sent to the analog-digital conversion circuit 1204 to be processed, and when the received signal is a narrowband signal, the frequency selection module 1203 is configured to perform frequency selection processing on the received signal.

The receiver 1202 includes a signal filtering and amplifying circuit and a signal shaping circuit. The signal filtering and amplifying circuit comprises a differential amplifying circuit and a fourth-order Butterworth filter. The differential amplifying circuit can be an SSM2212 chip. The filtering uses a fourth-order Butterworth filter composed of a second-order low-pass filter and a second-order high-pass filter, and a schematic diagram of the fourth-order Butterworth filter is shown in FIG. 11. The signal shaping circuit uses a voltage comparator to convert the sine wave into a corresponding square wave, which in a specific design can limit the amplitude of all signals to 2.5V. The voltage comparator may be TLC3702. A schematic diagram of the signal shaping circuit is shown in fig. 12.

After the shaped signal enters the frequency selection module 1203 via the receiver 1202, it is determined whether the input signal is a narrowband signal, and if so, the signal is further processed. The frequency selection module 1203 includes a narrow band pass filter constructed of multiple sets of capacitors and inductors. A schematic diagram of the frequency selection module 1203 is shown in fig. 13. Wherein the inductance parameter determines its specific frequency selective characteristics. And obtaining the selected values of L and C according to a specified frequency requirement by a cut-off frequency calculation formula (5) of the capacitive-inductive filter.

Formula (5)

Wherein f ₀ is the cut-off frequency of the capacitive-inductive filter, L is the inductance and C is the capacitance.

It can be found from the calculation that c1=4700 pF for signal 1 pass frequency 13 khz:l1=32 mh, c2=3600 pF for signal 2 pass frequency 15 khz:l2=31 mh, c2=29 mh for signal 3 pass frequency 17 khz:l3=3000 pF.

The transceiver device 140 includes a wireless coil 1401 and a transducer 1402, the wireless coil 1401 being used in an aquatic environment and the transducer 1402 being used in an underwater environment to accommodate both different working environments on water and underwater. On the surface, the on-board transceiver exchanges information with the transponder via wireless coil 1401 in an electromagnetic induction manner, and under water, the on-board transceiver communicates with the transponder via transducer 1402 in acoustic signal communication.

The wireless coil 1401 configuration and material selection is optimized in the present application in view of the relatively open water environment and less interference factors. In practice, the wireless coil 1401 may use 10-turn copper wires to increase the magnetic flux of the electromagnetic field and use silicone rubber to perform vulcanization reaction, completely ensuring its sealability. The structure of the wireless coil is shown in fig. 14.

As shown in fig. 1, the transmitting unit 130 is mainly responsible for generating and transmitting signals, and is specifically used for driving the transceiver device 140 to transmit signals to communicate with the transponder, wherein different communication circuits are provided for different transceiver devices, and specifically, the transmitting unit 130 includes a wireless coil communication circuit used on a deck, a transducer communication circuit used underwater, and a digital-to-analog conversion circuit (i.e., D/a circuit). Fig. 15 shows a block diagram of the structure of the transmitting unit, as shown in fig. 15, using two different sets of driving circuits and power amplifiers for different transceiving devices. The transmitting unit comprises a wireless coil communication circuit, a transducer communication circuit and a digital-to-analog conversion circuit 1301, wherein the wireless coil communication circuit comprises a linear power amplifier circuit 1302 and a filter 1303, the linear power amplifier circuit 1302 is used for driving the wireless coil 1401 to transmit signals, the transducer communication circuit comprises a class-D power amplifier circuit 1304 and a transmission driving circuit 1305, the class-D power amplifier circuit 1304 is used for driving the transducer 1402 to transmit signals, the class-D power amplifier circuit 1304 is a class-D audio power amplifier and is sometimes called a digital power amplifier circuit, and the transmission driving circuit 1305 is used for carrying out current enhancement and dead zone processing on the transmitted signals.

To be able to drive the wireless coil 1401 into operation, the linear power amplifier 1302 may use a linear power amplifier LM 386. When LM386 is used, the LM386 minimum gain circuit is shown in fig. 16 by configuring it into minimum gain mode without adding any gain setting resistor and capacitor between pins 1 and 8.

The transmit driver circuit 1305 receives the processor 1101, followed by the class D power amplifier circuit 1304, and performs current boosting and dead zone processing on the transmit signal. The transmitting signal is divided into positive and negative directions by a CD4013B chip, then transmitted to a MOS tube driving chip CD54HC40103, and the chip guides the signal to a D-type power amplifier circuit and finally output by the power amplifier. A schematic diagram of the emission drive circuit 1305 is shown in fig. 17.

In order to ensure the circuit safety, the two waveforms of the class D power amplifier circuit 1304 are slightly delay-adjusted, and the waveform timing diagram is shown in fig. 18, wherein U5-Q2 represents the waveform of the Q2 pin of the U5 element, U5-Q1 represents the waveform of the Q1 pin of the U5 element, U5-Q1 'represents the waveform of the Q1' (i.e., Q1-) pin of the U5 element, U8-1Y represents the waveform of the 1Y pin of the U8 element, and U8-4Y represents the waveform of the 4Y pin of the U8 element. By introducing the time difference, the simultaneous starting of the MOS power tube is effectively avoided, and the risk of circuit conflict is reduced.

The class D power amplifier circuit 1304 may select IRL8113S as a power tube, and use 12.6V for power supply. The 180dB sound source level for the index requirement is calculated from the parameters of transducer 1402, requiring 400V voltage drive with 25V drain-source voltage. Thus, the transformer transformation ratio is:

Formula (6)

Where n is the transformer transformation ratio, U _L is the required voltage, and U _i is the drain-source voltage.

In the application, the processor is always in a power-on state, and the transmitting unit and the receiving and transmitting equipment are in a standby low-power-consumption state. The overall power consumption of the shipborne transceiver is not larger than 50mA under the condition that the class D power amplifier does not emit, so that the power consumption of the shipborne transceiver is effectively reduced, and the standby time of the shipborne transceiver is prolonged. In order to overcome the problems of multipath effect, acoustic attenuation and the like existing in the process of propagation of underwater acoustic signals, the shipborne transceiver can effectively improve the ranging precision and the anti-interference performance of communication of the shipborne transceiver through the hardware circuits of the transmitting unit and the receiving unit and the detection algorithm design of broadband signals and narrowband signals.

The invention also provides an underwater sound positioning system which comprises a command protocol design module, a signal processing module and the shipboard transceiver used in the underwater sound positioning system. The instruction protocol design module is used for carrying out protocol design on a downlink instruction of the on-board transceiver to the transponder and an uplink instruction of the transponder to the on-board transceiver, wherein a plurality of groups of the transponder are divided, a plurality of channels are divided for each group to form a plurality of transponder combinations, and the signal processing module is used for carrying out signal processing on a received signal by adopting a preset algorithm.

According to the working function of the ship-borne transceiver, the software structure of the underwater sound positioning system can be divided into four main parts, namely ranging, address coding, electric quantity detection and transceiver power detection. The overall software architecture is consolidated into a framework diagram, as shown in fig. 19. The system is ready, receives a button instruction, receives a receiving and sending device to judge, if the working environment is an underwater environment, transmits an inquiry signal through a transducer, if the working environment is an above-water environment, transmits an inquiry signal through a wireless coil, and performs polling reception by an ADC to judge whether the received signal is correct, if the received signal is correct, then carries out instruction type judgment, if the received signal is incorrect, the display sends out failure prompt, when the received signal is judged to be in a response function by the instruction type, the response detection is carried out, the display sends out success prompt, the buzzer sends out sound, when the received signal is judged to be in a ranging function by the instruction type, the distance is calculated, the display displays the distance, when the received signal is judged to be in an identity code (namely address code) function by the instruction type, the response detection is carried out, the display sends out success prompt, the buzzer sends out sound, when the received signal is judged to be in an electric quantity detection function by the instruction type, the electric quantity is calculated, and the display displays voltage when the received signal is judged to be in the system by the receiving and sending device. In order to realize the functions, the whole software design is divided into a plurality of parts, namely instruction protocol design, signal processing algorithm and system software implementation.

For example, in a protocol designed for an underwater acoustic positioning system, transponders are divided into 128 different groups, each group being subdivided into 8 different channels, which together constitute 1024 transponder combinations, which can achieve the coordinated target positioning of 1024 transponders.

The downlink instruction includes an instruction protocol for implementing each function, and may specifically include an inquiry instruction, an address coding instruction, an electric quantity detection instruction, and a ranging instruction.

The instruction protocol design module is further used for forming a plurality of frequency combinations by combining a plurality of frequencies to form a plurality of frequency combinations as information codes by using a plurality of frequencies as guide codes according to an inquiry instruction, combining the plurality of frequency combinations with a plurality of time division strategies to obtain a plurality of different frequency-time division combinations, adopting a binary frequency shift keying modulation mode according to an address coding instruction, wherein each code element is distributed to one of two preset different frequencies according to the value of the code element, setting the address coding instruction to comprise the guide codes, the information codes and check codes, setting the information codes by using the different frequencies according to an electric quantity detection instruction by using the positive rotation pulse of the first preset frequency as the guide codes, forming the plurality of frequency combinations by using the plurality of frequencies as the information codes by combining the two pairs according to a ranging instruction, combining the plurality of frequency combinations with the plurality of time division strategies to obtain a plurality of different frequency-time division combinations, and carrying out signal processing time delay measurement processing.

Specifically, the interrogation command uses four frequencies f1, f2, f3 and f4, wherein the frequency f1 is a first preset frequency. The forward pulse of f1 (i.e., the CW pulse) is used as a pilot code to inform the transponder of the arrival of the interrogation signal. Then, three different frequency combinations are formed as information codes (or referred to as information chips) by combining two by two with the remaining three frequencies. By combining these frequency combinations with 43 different time division strategies, a total of 128 different frequency division time division combinations can be obtained. A schematic diagram of an interrogation instruction is shown in fig. 20. The total length of the interrogation instruction may be τ. The inter-code interval a is incremented by 5ms each time from τ1, and the inter-code interval b is decremented by 5ms each time from τ2, for a total of 43 time-division protocol variations. The ranging instruction is the same as the inquiry instruction, and only further performs signal processing and delay measurement.

The address coding instruction adopts a Binary Frequency Shift Keying (BFSK) modulation mode, and each code element is allocated to one of two preset different frequencies according to the value (0 or 1). To improve signal reliability and reduce the effects of multipath interference, each set of address coded instructions may include three parts, a pilot code, an information code, and a check code. A schematic diagram of an address coded instruction is shown in fig. 21. The last bit in the address encoded instruction is a check code, and the signal accuracy is determined by parity checking. If the sum is odd, the check code is set to 1, and if the sum is even, the check code is set to 0.

The power detection command takes the CW pulse of f1 as the pilot code, the first information code is set to f5, and the last information code is set to f0 to ensure that the power detection command is not repeated with the interrogation command, and a schematic diagram of the power detection command is shown in fig. 22.

The uplink instruction is mainly used for realizing response instructions and electric quantity detection uplink instructions, and the ranging uplink instruction, the address coding uplink instruction and the response instructions are consistent. The uplink instructions comprise response instructions and electric quantity detection uplink instructions, and the response instructions comprise narrowband signal response instructions and broadband signal response instructions. The instruction protocol design module is further used for responding to the instruction by using the narrowband signal, taking the forward rotation pulse as a response signal, taking the signal with the second preset frequency as a guide code, combining the signal with the second preset frequency into a plurality of frequency combinations by utilizing a plurality of frequencies to form a plurality of response channels, and setting the total length of the response instruction of the narrowband signal. For example, the narrowband signal response command uses CW pulses as the reply signal, the frequency f11 is a second preset frequency, the signal of the frequency f11 is used as the pilot code, and then the 5 frequencies f12, f13, f14, f15 and f16 are divided into 8 groups in pairs to form 8 different reply channels. Fig. 23 shows a schematic diagram of a narrowband signal response command, and as shown in fig. 23, the total length of the narrowband signal response command is fixed to τ, the inter-code interval a is τ1, and the inter-code interval b is τ2.

The wideband signal response instructions include wideband chirp signal response instructions and wideband spread spectrum signal response instructions. The instruction protocol design module is further used for responding to the instruction by adopting a plurality of frequencies as center frequencies for the broadband linear frequency modulation signal, setting the bandwidth and duration of the signal of each frequency, and utilizing a pseudo random sequence as a broadband spread spectrum signal of a transponder for responding to the instruction by the broadband spread spectrum signal.

For example, for a wideband chirp response command, the center frequency may take 8 different frequencies, each with a 2kHz bandwidth and a duration τ0. For the broadband spread spectrum signal response instruction, a Gold sequence with 127 bits long generated by a 7-order m sequence can be selected as the broadband spread spectrum signal response instruction of the transponder, and 8 balanced Gold sequences are selected.

The instruction protocol design module is further used for detecting an uplink instruction by taking a forward pulse with a second preset frequency as a guide code, and adopting an information code with a preset bit number to represent the electric quantity of the transponder, wherein each code element adopts a binary frequency shift keying modulation mode, and a check code is set. The electric quantity detection uplink instruction also adopts a binary frequency shift keying modulation mode. The CW pulse with frequency f11 is used as a pilot code, and then 10-bit information codes are used to represent the electric quantity of the transponder, wherein each code element adopts BFSK modulation mode, 0 code element corresponds to f12,1 code element corresponds to f13, and the last bit check code determines the accuracy of the signal through parity check.

In the shipborne transceiver, the detection of the narrowband signal is realized through a hardware circuit, and whether the signal arrives or not is detected through the level state of the GPIO interface, specifically, a processor in a processing unit of the shipborne transceiver is connected with the output end of the frequency selection module, and whether the narrowband signal arrives or not is detected through the level state of the GPIO interface. Fig. 24 shows a schematic flow chart of narrowband signal detection. As shown in fig. 24, the transceiver receives signals, the receiver receives signals, judges whether the frequency selection network recognizes the 33kHz pilot code, if the 33kHz pilot code is recognized, the signals are sent to the processor GPIO, the processor judges the signals as single frequency signals and prepares to judge other frequency selection networks GPIO, and then judges whether the first bit information code is received, if the first bit information code is received, the second bit information code is continuously judged, if the second bit information code is received, the time delay is accurate, the transponder response is judged to be successful, if the first bit information code is not received, or the second bit information code is not received, or the time delay is inaccurate, the transponder response is judged to be failed, if the 33kHz pilot code is not recognized, the access processor AD starts to collect data, and other forms of signal detection are performed.

When the frequency-selecting network recognizes the boot code, the GPIO interfaces of all frequencies are opened and set to an input state. A timer is then used for accurate time control. The on-board transceiver will begin the windowing test 100ms from the leading edge of the boot code. The on-board transceiver will again window detect when it is spaced by τ from the leading edge of the boot code. In this way the frequency and time of arrival of the pilot code and the two-bit information code can be determined. The identification method not only improves the accuracy of signal reception, but also is beneficial to reducing the influence of environmental multi-path on signal reception.

The time resolution of the wideband linear frequency modulation signal can be improved by a pulse compression technology due to the time bandwidth product characteristic of the wideband linear frequency modulation signal, and the wideband signal is resolved by adopting a correlation method in order to improve the accurate identification capability of the arrival time of the interrogation signal. The signal processing module is further used for resolving the broadband signal by adopting a frequency domain fast correlation method and detecting the broadband signal by adopting a spread spectrum signal identification method based on code division multiple access.

The copy correlators in the broadband signal detection are in discrete form during processing. Assuming two causal signals x (n) and y (n), a convolution calculation strategy may be used to calculate the correlation of the two signals x (n) and y (n). In the present application, the signal processing module may perform convolution operation using frequency domain multiplication, which converts the signal to the frequency domain through FFT and then returns to the time domain through IFFT. The linear convolution expression of the sequence x (n) with length L and the sequence y (n) with length M is:

formula (7)

Wherein z (n) is the output sequence, y (l) is the reference signal 1, x (n-l) is the reference signal 2, and M is the length of the y (n) sequence.

Then the length of z (N) is L+M-1, when the cyclic convolution is equal to the linear convolution, the situation that the cyclic convolution is aliased on the frequency domain can be avoided, and N is larger than or equal to L+M-1, so that the method is obtained:

Formula (8)

Formula (9)

The specific expression is then as follows:

Formula (10)

Formula (11)

Formula (12)

Formula (13)

Fig. 25 shows a schematic diagram of frequency domain fast correlation, as shown in fig. 25, the Y (N) sequence is first flipped and the N-point FFT is performed to obtain Y (k). And then N-point FFT is carried out on the sequence X (N) to obtain X (k). Z (k) is obtained through multiplication operation, and N-point IFFT operation is carried out on Z (k) to obtain Z (N).

In signal processing of a real-time system, when a situation that frequency domain fast correlation calculation needs to be performed on a long input sequence x (n) and a short reference signal y (n) is faced, direct processing can cause a surge in computational resource requirement due to the fact that y (n) needs to be subjected to a large amount of zero padding. FIG. 26 shows a second schematic diagram of a frequency domain fast correlation, in which the present application proposes a fast sliding correlation using an overlap-save method, and the steps are that there is a sequence y (N) of length M, the input sequence x (N) is divided into several parts of equal length L, L is approximately equal to M, then y (N) is supplemented with M-N0 to obtain y _N (N), the expression of N is N= ^k +.L+M-1, the first sequence divided into L is supplemented with N-L zeros, then it is fast correlated with y _N (N) in frequency domain, the correlation output of N points is obtained, the first M-1 points are truncated, the rest of the parts are reserved, and the remaining parts are combined each time, thus obtaining the output sequence z (N).

A processor in the underwater sound positioning system collects data in real time through the ADC, and a program is designed to realize a multi-stage buffer area. The algorithm is adapted to the signal processing module and is used for meeting the real-time signal processing requirement. The length of the reference signal is set to be N, the reference signal is expanded to 2N points by adding zero, the buffer areas are set to be N, two buffer areas are arranged in total, an overlapping reservation method is adopted, the front N points of the two buffer areas are linked with the rear N points of the last buffer area, and the rear N points are new data acquired by the current buffer area. And then the data of each buffer area is related to the local signal, and the rear N point of the related result is reserved as a related output sequence. The rapid sliding related scheme of the system effectively improves the data processing speed, and ensures that the underwater sound positioning system can realize efficient real-time signal detection and processing.

When the processor performs copy related calculation on the received signal, a large amount of zero padding operation is required to be performed on the reference signal, and a large amount of memory and calculation capacity are required to be consumed.

In the wideband signal detection of the present application, spread spectrum signal identification based on Code Division Multiple Access (CDMA) technology is introduced, which allows multiple users to communicate simultaneously within the same frequency band through unique pseudo-random sequence codes assigned to each user. Pseudo-random sequences may be used in spectrum spreading, known as spreading code sequences. Fig. 27 shows a schematic diagram of a mathematical model of a spread spectrum communication transmitter system, as shown in fig. 27, whose output signal expression is:

Formula (14)

Wherein f ₀ is the carrier center frequency, A is the amplitude of the signal,For the initial phase of the carrier wave,For binary sequence controlled carrier phase, d (t) and c (t) in fig. 27 are spreading code waveforms.

Satisfying equation (14), the encoded data stream { a _n } is represented by d (t), and the transmission signal s (t) is:

formula (15)

Gold sequences are employed as pseudo-random sequences in the present application. The protocol selects 8 balanced Gold sequences with 127 bits generated by 7-order m sequences as broadband spread spectrum signal response instructions of the transponder, the modulation carrier frequency is 24kHz, and the protocol has the characteristics of excellent autocorrelation and low cross correlation value. The balanced Gold sequence has excellent autocorrelation and zero cross correlation, and is suitable for being used as a broadband spread spectrum signal response instruction of a transponder.

The description of the implementation flow of various functions of the underwater sound positioning system of the present application is as follows, in combination with the above related description of hardware and software.

The ranging function is that during an interrogation response, the onboard transceiver sends an interrogation command to the transponder and then waits for the transponder's response signal by polling the ADC. The time difference between sending the interrogation command and receiving the reply signal is measured so that the underwater sound location system can calculate the distance traveled by the signal. Fig. 28 shows a schematic flow chart of the ranging function, as shown in fig. 28, after receiving the ranging command, the transmitter (i.e. the transceiver) transmits an inquiry command, processes a signal to receive a response signal, calculates the distance if the response is successful, and displays the distance if the response is failed, and displays failure.

In the underwater sound positioning system, the address coding function is mainly used for the laying work of the transponder. It not only uses the inquiry response function, but also requires knob input and screen control to enhance user interactivity and intuitive nature of operation. Through the knob matrix, an operator can easily set or adjust the address of the transponder, the screen control function displays operation feedback and the configuration state of the address in real time, the address coding function simplifies the transponder arrangement flow, and the user experience of the communication system is improved. Fig. 29 shows a flow chart of the address coding function, as shown in fig. 29, in which an address coding command is received, a knob identification code number is read, and a 10-bit information code is generated according to the number, the coding command is transmitted for the first time, the coding command is transmitted for the second time, the transmitter transmits an inquiry command, the signal processing receives a response signal, if the response is successful, the display is successful, and if the response is failed, the display is failed.

The power detection function is to decode the narrowband signal to obtain power information of the transponder. Which extracts the 10-bit information code and the 1-bit check code transmitted by the transponder by detecting and analyzing the signal using the frequency selective network. The 10-bit information code contains numerical information of the transponder power, and the check code is used for ensuring the integrity and accuracy of the received data. Fig. 30 shows a flow chart of the electric quantity detection function, as shown in fig. 30, in which an electric quantity detection instruction is received and transmitted, a frequency selection network is used to detect and analyze signals to extract each information code and check code, whether each information code is correct, whether the time delay is correct, whether the check code is correct, if any information code is incorrect, or the time delay is incorrect, or the check code is incorrect, the display displays that the electric quantity detection fails, and if all the information codes, the time delay and the check code are correct, the electric quantity is calculated, and the display displays the electric quantity.

The self-checking function of the electric quantity of the shipborne transceiver is realized by monitoring the power state of the equipment in real time. The function firstly carries out button polling to confirm initiation of electric quantity self-checking, after receiving an on-board transceiver electric quantity self-checking instruction, the function is connected with a battery electric quantity detection circuit and a processor through an I ² C bus, the on-board transceiver electric quantity self-checking is started, a battery detection IC then starts a voltage acquisition program to calculate a voltage value, a display displays the voltage value, and a flow diagram of the on-board transceiver electric quantity self-checking function is shown in fig. 31.

According to the technical scheme provided by the embodiment of the application, two transceiver devices of the wireless coil and the transducer are respectively designed according to different use requirements of a transponder deck and underwater, and the on-board transceiver can well meet the interaction requirements of the transponder under various use scenes through electromagnetic induction, underwater sound communication modes and corresponding hardware circuits; the on-board transceiver adopts a frequency selection module to conveniently complete detection of narrowband signals, a processor is connected with the output end of the frequency selection module, the processor detects whether narrowband signals arrive through the level state of a GPIO interface, in the detection process, the processor only needs to use a timer to determine the arrival time of each forward rotation pulse without complex software processing algorithm, thereby effectively reducing the power consumption of the whole machine, the on-board transceiver conveniently completes the instruction protocol design of the downlink instructions of the transponders by combining time division and frequency division technology, the interrogation instructions select a plurality of frequency signal combinations to be combined with a plurality of different time division strategies, different interrogation codes are defined for a plurality of groups of transponders, the address coding instructions adopt a binary frequency shift keying modulation mode, the reliability of the signals is effectively improved and the multipath interference is reduced through the combination of a guide code, an information code and a check code, in the detection process of broadband signals, each transponder is allocated with a unique address code by using a code division multiple access technology and a spread spectrum technology, the on-board transceiver can work simultaneously in the same frequency band without mutual interference, the correlation sequence is greatly improved, the correlation sequence is completely calculated by using the correlation sequence, and the correlation sequence is completely calculated according to the correlation sequence is completely, and the correlation sequence is completely calculated by using the correlation sequence is completely, and the correlation sequence is completely calculated according to the sequence is completely reduced, in order to overcome the problems of multipath effect, sound wave attenuation and the like existing in the underwater sound signal during propagation, the shipborne transceiver can effectively improve the ranging precision and the anti-interference performance of communication of the shipborne transceiver through the hardware circuits of a transmitting unit and a receiving unit and the detection algorithm design of broadband signals and narrowband signals.

The algorithms and displays presented herein are not inherently related to any particular computer, virtual system, or other apparatus. Various general-purpose systems may also be used with the teachings herein. The required structure for a construction of such a system is apparent from the description above. In addition, the present invention is not directed to any particular programming language. It will be appreciated that the teachings of the present invention described herein may be implemented in a variety of programming languages, and the above description of specific languages is provided for disclosure of enablement and best mode of the present invention.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Those skilled in the art will appreciate that the modules in the apparatus of the embodiments may be adaptively changed and disposed in one or more apparatuses different from the embodiments. The modules or units or components of the embodiments may be combined into one module or unit or component and, furthermore, they may be divided into a plurality of sub-modules or sub-units or sub-components. Any combination of all features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or units of any method or apparatus so disclosed, may be used in combination, except insofar as at least some of such features and/or processes or units are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features but not others included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments may be used in any combination.

Various component embodiments of the invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that some or all of the functions of some or all of the components in accordance with embodiments of the present invention may be implemented in practice using a microprocessor or Digital Signal Processor (DSP). The present invention can also be implemented as an apparatus or device program (e.g., a computer program and a computer program product) for performing a portion or all of the methods described herein. Such a program embodying the present invention may be stored on a computer readable medium, or may have the form of one or more signals. Such signals may be downloaded from an internet website, provided on a carrier signal, or provided in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, third, etc. do not denote any order. These words may be interpreted as names.

Claims (10)

1. A shipborne transceiver for use in an underwater acoustic positioning system, the shipborne transceiver comprising a processing unit, a receiving unit, a transmitting unit and a transceiving device;

The processing unit comprises a processor and a peripheral circuit of the processor, wherein the processor is used for converting analog signals and digital signals, and the peripheral circuit comprises an operation panel circuit, a power supply circuit, a battery electric quantity detection circuit and a battery charging protection circuit;

The receiving unit comprises a function selecting module, a receiver, a frequency selecting module and an analog-digital conversion circuit; the function selection module is used for changing the working environment of the shipborne transceiver and receiving signals of the transponder through the transceiver equipment, the receiver is used for preprocessing the received signals and then selecting the received signals according to signal forms to send the received signals to the frequency selection module or the analog-digital conversion circuit, and the frequency selection module is used for carrying out frequency selection processing on the received signals when the received signals are narrowband signals;

the transmitting unit is used for driving the transceiver to transmit signals so as to communicate with the transponder;

The transceiver device includes a wireless coil for use in an aquatic environment and a transducer for use in an underwater environment.

2. The shipboard transceiver for use in an underwater sound location system of claim 1, wherein the operation panel circuit comprises a button control circuit, a display screen control circuit, and a buzzer driving circuit;

The button control circuit comprises a knob matrix circuit and a debounce reset switch circuit;

the display screen control circuit is used for driving a display to enable the display to display real-time state information of the shipborne transceiver;

the buzzer driving circuit is used for driving the buzzer to sound when the on-board transceiver successfully receives the feedback of the transponder after sending the instruction.

3. The shipboard transceiver for use in an underwater sound location system of claim 1, wherein the receiver comprises a signal filtering amplification circuit and a signal shaping circuit;

The signal filtering and amplifying circuit comprises a differential amplifying circuit and a fourth-order Butterworth filter;

the signal shaping circuit converts the sine wave into a corresponding square wave using a voltage comparator.

4. The shipboard transceiver for use in an underwater sound location system of claim 1, wherein the frequency selection module comprises a narrow band pass filter constructed from multiple sets of capacitors and inductors.

5. The shipboard transceiver for use in an underwater sound location system of claim 1, wherein the transmitting unit comprises a wireless coil communication circuit, a transducer communication circuit, and a digital-to-analog conversion circuit;

the wireless coil communication circuit comprises a linear power amplifier circuit and a filter, wherein the linear power amplifier circuit is used for driving the wireless coil to transmit signals;

The transducer communication circuit comprises a class D power amplifier circuit and a transmitting driving circuit, wherein the class D power amplifier circuit is used for driving a transducer to transmit signals, and the transmitting driving circuit is used for carrying out current enhancement and dead zone processing on the transmitted signals.

6. The on-board transceiver for use in an underwater sound location system according to any of claims 1-5, wherein the processor is connected to the output of the frequency selection module and detects whether a narrowband signal is coming through the level state of the GPIO interface.

7. An underwater sound location system comprising a command protocol design module, a signal processing module, and an on-board transceiver for use in an underwater sound location system as claimed in any of claims 1 to 6;

The instruction protocol design module is used for carrying out protocol design on a downlink instruction of the shipborne transceiver to the transponder and an uplink instruction of the transponder to the shipborne transceiver, wherein a plurality of groups of transponders are divided, a plurality of channels are divided for each group of transponders, and a plurality of transponder combinations are formed;

the signal processing module is used for performing signal processing on the received signal by adopting a preset algorithm.

8. The underwater sound location system of claim 7, wherein the downlink instructions comprise an interrogation instruction, an address coding instruction, a power detection instruction, and a ranging instruction;

the instruction protocol design module is further configured to:

aiming at the inquiry instruction, forward rotation pulses with a first preset frequency are used as guide codes, a plurality of frequency combinations are formed by combining a plurality of frequencies in pairs to be used as information codes, and the plurality of frequency combinations are combined with a plurality of time division strategies to obtain a plurality of different frequency division time division combinations;

aiming at the address coding instruction, a binary frequency shift keying modulation mode is adopted, each code element is distributed to one of two preset different frequencies according to the value of the code element, and the address coding instruction is set to contain a guide code, an information code and a check code;

aiming at the electric quantity detection instruction, taking forward rotation pulses with a first preset frequency as a guide code, and setting information codes by utilizing different frequencies so that the electric quantity detection instruction is different from the inquiry instruction;

And aiming at the ranging instruction, taking forward rotation pulses with a first preset frequency as a guide code, forming a plurality of frequency combinations by combining a plurality of frequencies to be taken as an information code, combining the plurality of frequency combinations with a plurality of time division strategies to obtain a plurality of different frequency-division time-division combinations, and performing signal processing and delay measurement processing.

9. The underwater acoustic positioning system of claim 7, wherein the uplink instructions comprise a response instruction and an electrical quantity detection uplink instruction, wherein the response instruction comprises a narrowband signal response instruction and a wideband signal response instruction, wherein the wideband signal response instruction comprises a wideband chirp signal response instruction and a wideband spread spectrum signal response instruction;

the instruction protocol design module is further configured to:

Aiming at the narrowband signal response instruction, taking a forward rotation pulse as a response signal, taking a signal with a second preset frequency as a guide code, combining a plurality of frequencies into a plurality of frequency combinations by utilizing a plurality of frequencies to form a plurality of response channels, and setting the total length of the narrowband signal response instruction;

Aiming at the broadband linear frequency modulation signal response instruction, adopting a plurality of frequencies as center frequencies, and setting the bandwidth and duration of signals of each frequency;

Aiming at the broadband spread spectrum signal response instruction, a pseudo-random sequence is used as a broadband spread spectrum signal response instruction of a transponder;

And aiming at the electric quantity detection uplink instruction, taking a forward pulse with a second preset frequency as a guide code, and adopting an information code with a preset bit number to represent the electric quantity of the transponder, wherein each code element adopts a binary frequency shift keying modulation mode, and a check code is set.

10. The hydroacoustic positioning system of any of claims 7-9, wherein the signal processing module is further to:

And resolving the broadband signal by adopting a frequency domain fast correlation method, and detecting the broadband signal by adopting a spread spectrum signal identification method based on code division multiple access.