2041 results about "Hydroacoustics" patented technology

The invention discloses a penetration probe-based deep sea multi-element comprehensive observation system, which comprises an upper computer and a data recovery cabin, wherein the upper end and the lower end of the data recovery cabin are connected with a probe rod through a hydraulic separation releaser and a launching device respectively; a small-sized pile driver is arranged in the launching device; the launching device is provided with an underwater search light, an underwater camera and an underwater acoustic communication transceiver; the top of the data recovery cabin is provided with a floating body; a central controller is included in the data recovery cabin; the outer side face of the data recovery cabin is provided with an underwater acoustic transducer; and the outer surface of the probe rod is provided with more than 10 annular electrodes and more than 2 pore water pressure sensors which are connected with the central controller. The system has a simple structure, is reliable in work and accurate in control, can carry various sensors and adapt to a deep sea high pressure environment, and can synchronously and automatically observe and record states and changes of sea water and sediments within a 10m depth range close to a sea water-sediment interface with over 2,000m water depth, including the state of sediments of 6-7m below a sea bottom surface, the condition ofsea water of a bottom layer of 3-4m above the sea bottom surface and the dynamic change in position of the sea bottom surface.

The invention discloses a kind of underwater GPS allocation and navigation system and method without high stable frequency scale. The system is made up of GPS satellite constellation, four or more GPS floating marks, underwater navigation transceiver, data control centre, sea level wireless communication loop and hydroacoustics communication loop. The method is: when the object underwater needed to be located, the underwater navigation transceiver sends out hydroacoustics localization signal to the GPS floating mark, the floating mark transmits the hydroacoustics localization signal, the GPS signal and the posture calibration data wirelessly to the data control centre, and the data are processed with the difference signal, works out the position and time sending out the localization signal of the underwater object, the position and time data are transmitted to the underwater navigation transceiver by the hydroacoustics communication system, it can carry on navigation or time service. The invention can be applied to underwater object tracing, underwater localization and navigation, underwater precise timer service, measuring project control and project structure sample, it needs no high stable frequency scale.

The invention relates to an underwater target tracking and positioning method, which comprises the following steps that: a central processing unit transmits a starting instruction and required positioning data rate information to a blue and green laser transmitting and receiving integral rotatable device, scans an underwater responder, and transmits a laser signal containing the data rate information to the underwater responder; the underwater responder reflects the laser signal according to the prior path, and a transducer is opened; after the reflected laser signal is received, the transducer transmits a synchronous timing signal to the central processing unit, and the central processing unit begins timing; the underwater responder transmits a periodical frequency hopping pulse signal of corresponding data rate to a hydrophorce according to the data rate information; the hydrophorce transmits a direct signal to the central processing unit; and the central processing unit calculates distance information, corrects the coordinate and calculates the coordinate of the underwater responder. The invention also relates to an underwater target tracking and positioning system. The invention adopts a blue and green laser synchronous time synchronization mechanism and a hydroacoustic frequency hopping mechanism to solve the problems of synchronous error and multi-path interference in the prior short-baseline hydroacoustic positioning system respectively.

Methods and systems for moving seismic streamer steering devices to target positions are disclosed. One method comprises calculating forces required to steer one or more seismic streamer steering devices in a seismic spread to target positions, the calculated forces based wholly or in part on information in modulated underwater acoustic transmissions, and steering the streamer steering devices to the target positions using the calculated forces. It is emphasized that this abstract is provided to comply with the rules requiring an abstract, which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

The invention provides a depth neural network system and a method based on modulation mode identification of underwater acoustic communication. The system comprises: a data preprocessing part for preprocessing data of a plurality of modulation modes transmitted through underwater acoustic communication; A first layer neural network generates a feature extraction set of the first layer according toa plurality of modulation mode data transmitted from the pretreated underwater acoustic communication; The second layer neural network generates the second layer high-level feature set; The third layer neural network generates higher level feature set, the fourth layer neural network classifies and identifies the initial data by the feature set extracted in front; The fifth layer is the neural network layer, which generates the final modulation mode judgment and outputs the identified modulation mode. The depth neural network system and method based on the modulation mode recognition of underwater acoustic communication can simulate the actual use situation, improve the use effect in the actual underwater acoustic communication, more conveniently and efficiently complete the modulation recognition of underwater acoustic communication, and improve the accuracy of recognition and judgment.

The invention relates to a method of using a reverberation pool to carry out reciprocity calibration of an underwater acoustic transducer. The method of using a reverberation pool to carry out reciprocity calibration of an underwater acoustic transducer includes the steps: 1) according to the lowest frequency to be calibrated for an underwater acoustic transducer to be calibrated, selecting a reverberation pool with the corresponding size; 2) using any one nondirectional sound source and one hydrophone to form an emission / reception energy transducer pair, measuring the output voltage of an open circuit being 1m away from a sound source equivalent sound center in the reverberation pool and recording the emission / reception parameters of the apparatus; and 3) placing the emission / reception energy transducer pair in the reverberation pool, adjusting the same emission / reception parameters, and using a space averaging method to measure the output voltage of the open circuit of the hydrophone. If the method of using a reverberation pool to carry out reciprocity calibration of an underwater acoustic transducer is used to perform calibration of an underwater acoustic transducer, a plurality of hydrophones can be calibrated at the same time, so that the requirement for the experiment pool is reduced. Therefore, even in a reverberation pool with small size or a non anechoic pool, the method of using a reverberation pool to carry out reciprocity calibration of an underwater acoustic transducer can also be used for calibration only when the frequency range for calibration is satisfied.

The invention provides a wireless and underwater sound communication buoy, which is of a cordwood-type structure and comprises a VHF (Very High Frequency) antenna, a GPS (Global Positioning System) antenna, an antenna watertight base, a navigation light, a wireless support rod upper section, a hard polyurethane foam body, an antenna support rod lower section, a watertight electronic instrument cabin, a water-resistance load-bearing cable, a receiving / transmitting combined transducer and lead fish in sequence from top to bottom. The wireless and underwater sound communication buoy is characterized by further comprising a wireless communication module, an underwater sound communication module, a comprehensive controlling / processing module and a battery / power supply management and control module; the wireless communication module is used for realizing functions of a wireless communication data link layer and a physical layer; the water sound communication module is used for realizing the functions of an underwater sound communication data link layer and the physical layer; the comprehensive controlling / processing module is used for realizing the functions of a wireless and underwater sound communication network layer and an application layer and simultaneously realizes whole control on the buoy; and the battery / power supply management and control module is used for controlling, maintaining and managing a power supply.

The invention provides an ultra-wideband underwater acoustic transducer, which comprises an arc beam, a U-shaped beam, a transition block and a driving element, wherein the arc beam is a cylindrical shell, the section of which is elliptical arc; the U-shaped beam is a U-shaped curved translation body; the arc beam and the U-shaped beam form a flextensional shell, and two end faces of the flextensional shell are closed by cover plates; and the driving element and the transition block form a vibrator assembly, and the vibrator assembly is arranged in the flextensional shell and rigidly connected with the inner wall of the U-shaped beam. The ultra-wideband underwater acoustic transducer has the characteristics of low frequency, high power, compact structure, small size and light weight, and can be applied in the fields of underwater acoustic detection, antagonism, communication, measurement, marine resource exploration and the like.

The invention discloses a measuring method for network nodes of an underwater wireless sensor and a device. The method comprises the steps of: carrying out the interconversion of an electric signal and an ultrasonic signal by utilizing an ultrasonic transducer so as to complete underwater ultrasonic communication; calculating the relative distance between the nodes and the device by utilizing the transmission delay between node communication as well as the propagation velocity of ultrasound underwater; and collecting the underwater environmental data information from the position of the nodes by utilizing a sensor specially used in underwater detection. The device comprises a microcontroller, an FSK modulating and power amplifying module and a transducer which are connected in series; a hydrophone, a weak signal amplifier, an FSK demodulating chip and a microcontroller which are connected in series; a power management module is used for supplying power for a circuit and managing a power supply; and an external spreading interface module is used for connecting with a corresponding interface sensor and peripherals. The invention realizes the underwater sound communication function with low cost and low power consumption and the distance measuring function between the network nodes of the underwater wireless sensor.

A method and apparatus for determining the geophysical position of an autonomous underwater system utilizing underwater acoustic modems that exchange broadband underwater acoustic signals. The method of the invention includes the steps of initiating an exchange of broadband acoustic signals between the autonomous system of unknown geophysical position and a base system of known geophysical position wherein the depths of both systems is known. A bearing calculation is made on one of the signals transmitted between the systems, preferably through the use of an array of hydrophones placed closely together at predetermined locations on either the autonomous or base system. Also, the range between the two systems is determined by measuring the time of travel of at least one signal. By the acoustic transmission and sharing of information, as needed, about the known depths of the systems, the known geophysical position of the base system, and the range between the systems, sufficient data is gathered at one or both systems and used to determine the geophysical position of the autonomous system.

The invention discloses a method and a system for locating an underwater vehicle on basis of a global navigation satellite system (GNSS) satellite, wherein a plurality of locating buoys are additionally arranged on the water and carry GNSS receivers and underwater sound responders. The underwater vehicle carries the underwater sound responder. The locating buoys utilize a GNSS satellite location technique to complete self location and time service. When the underwater vehicle is needed to be located, the inquiry signal which is sent out by the underwater sound responder on the underwater vehicle is responded by the underwater responders on the locating buoys and then returns to the underwater responder. When the underwater vehicle simultaneously obtains at least 3 locating buoys which are distributed on the water and a certain resolving relation, the three-dimensional location coordinates of the underwater vehicle can be finally obtained. An underwater sound relative locating technology can be utilized to expand the GNSS water level precision locating capability towards underwater, so the underwater vehicle can directly obtain the self geodetic longitude and latitude coordinates at an operating submerged depth, and the locating precision is enabled to be at the same order of the GNSS water level locating precision.

Advantageous online and / or real-time OFDM-based underwater acoustic (UWA) apparatus, systems and methods are provided according to the present disclosure. The apparatus, systems and methods employ a receiver with a bank of parallel branches, with each branch having a self-correlator matched to a different waveform scaling factor. A detection is declared when any of the branches leads to a correlation metric larger than a pre-defined threshold. The branch with the largest metric yields a Doppler scale estimate and a coarse synchronization point. The proposed apparatus, systems and methods use one OFDM preamble, thereby avoiding the need to buffer the whole data packet before data demodulation and enabling online and / or real-time operation. Thus, the disclosed apparatus, systems and methods are advantageously applicable to UWA communications.

The invention discloses an amplitude and phase error correction method used for a linear array of an underwater acoustic transducer, and the method utilizes the feature that the relative value of rotation angle of a rotation mechanism of a water tank is easy to be precisely controlled, leads the array to be tested to gradually receive a plurality of test signals with different incident angles, andadopts a certain method for estimating a curve of incident directions of various test signals and amplitude and phase errors of each basic element in the array which are changed along with the incident angles, thereby being used for array amplitude and phase error correction. The method comprises the following steps: (1) obtaining the curve of the array amplitude and phase errors which are changed along with the incident angles by measurement and calculation; and (2) utilizing the curve of the array amplitude and phase errors which are changed along with the incident angles for carrying out correction on direction-of-arrival estimation (hereinafter referred to as DOA). The method has the advantages that the array correction method does not need to carry out micro-disturbance hypothesis onthe amplitude and phase errors of the array of the transducer, takes into consideration of inconsistency of the amplitude and phase errors of various array elements at the different incident angles,has a certain universal applicability and is particularly applicable to the correction of the high-frequency underwater acoustic transducer.

The invention discloses a fidelity enhanced beamforming method based on a distorted towed array, comprising the following steps: (1) simulating the radiation noise s(t) of an underwater acoustic target; (2) simulating the observation array signal xi(t), i =1,2,...,M, M is the number of elements in the towed array; (3) Roughly estimate the target orientation based on ideal beamforming as the steering angle when the target signal beam energy is maximum; (4) Detect the L of the target signal The line spectrum position l=1,2,...,L with the largest power; (5) Estimate the average delay difference △τi of each array element in the towed array from the phase difference at the strong line spectrum position, i=1 ,2,...,M; (6) Obtain fidelity-enhanced target tracking beam based on estimated time delay This method uses time delay estimation to correct the influence of distortion of the towed line array on beamforming, and obtain fidelity-enhanced target radiation Noise tracking beam.

The invention provides a multi-target data fusion method and system based on a hydroacoustic sensor network. The multi-target data fusion method comprises the following steps: (101) arranging a plurality of collecting nodes of the hydroacoustic sensor network in an observation area, arranging N collecting nodes in a water area, obtaining the azimuth information of a plurality of target elements, and transmitting the obtained azimuth information of the target elements to a main node, the N collecting nodes adopts line array hydrophones or vector hydrophones as detection parts, and the detection parts can process signals in real time, and the azimuth information of the target elements is observed by each collecting node in the observation area; and (102) fusing the data of the azimuth information of the target elements by the main node: associating data by the main node according to the azimuth information of the target elements and the information data of the targets stored in the main node by adopting the data associating strategy, and tracking and positioning the multiple targets to finish the track initiating, maintaining and deleting of the multiple targets.

The invention discloses a sonar target detection method based on the Faster R-CNN. According to the method, characteristic extraction is performed on targets in different complex underwater environments through utilizing the deep learning technology, the method is the major innovation and attempt compared with present sonar target detection methods, limitations of traditional methods are broken, deep characteristics of sonar images at the low SNR can be extracted, and good target detection and identification on the linear targets can be carried out. The sonar target detection and identification network based on the regional accelerated convolutional neural network (Faster-RCNN) is established to carry out target detection for sonar data. The method is advantaged in that good performance oflinear target detection of the sonar images is achieved, feasibility of the deep learning method in sonar target detection is verified, and a new research method is provided for characteristic extraction of the complex underwater acoustic environment data.

Methods and systems for moving seismic streamer steering devices to target positions are disclosed. One method comprises calculating forces required to steer one or more seismic streamer steering devices in a seismic spread to target positions, the calculated forces based wholly or in part on information in modulated underwater acoustic transmissions, and steering the streamer steering devices to the target positions using the calculated forces. It is emphasized that this abstract is provided to comply with the rules requiring an abstract, which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

The invention relates to an underwater moving object location and navigation method based on frequency spectrum transformation. In the method, (1) an onboard underwater sound transceiver transmits a symmetric triangle frequency modulation signal s(t) to an underwater moving object; (2) an underwater receiver array on an onboard measurement device receives echo signals; (3) the weight number of each array element in the underwater sound receiver array is adjusted by utilizing information of signals in the direction of an incoming wave; and (4) the onboard measurement device determines the coordinates of the underwater moving object in geodetic coordinates. An underwater moving object location and navigation device based on spectrum transformation mainly comprises the onboard measurement device, a shiphull posture correction device, an underwater sound transceiver on the underwater moving object, a water radio transceiver, an array signal processor, a GPS receiver and a microprocessor. The invention can not only track and locate the underwater object above water, seas on shore or in air, but also automatically locate and navigate underwater objects.

A method for emitting and combining underwater super wideband sound array includes applying underwater sound synthetic technique and multiarray emission technique of sub frequency channel and multimode vibration ¿C emission transducer to realize free selection of sweep frequency signal combination on sea detecting instruments and any program controlled adjustment of emission operating parameter. An emitting system device of underwater super wideband combined sound array is also disclosed.

The invention discloses a large-array underwater wideband spread spectrum beacon navigational positioning system and method based on time synchronization, and time synchronization is carried out on a positioning array buoy and a sound beacon through a high-accuracy time synchronization technology. The sound beacon subjected to strict time synchronization emits spread spectrum water sound signals in a timing mode. After the positioning array buoy receives the spread spectrum signals, the position of the sound beacon is obtained through signal resolution, distance calculation and position resolution. The position of the sound beacon is obtained after the coordinates are worked out, the movement track of the sound beacon can be drawn out through continuous response, resolving and positioning, and accurate positioning and navigation of underwater equipment are achieved.

The invention relates to a subaqueous multi-cable positioning system and a method thereof. The system comprises a data collection card, a main control machine and a plurality of dragging cables, wherein the data collection card and the main control machine are positioned on a water surface cable dragging ship, and the dragging cables are dragged by the cable dragging ship. Array elements comprising an acoustic energy transducer, a bathometer and a compass and a data transmission system comprising a data transmission packet are arranged in the dragging cables. The main control machine transmitsa positioning command to each array element, the array elements measure the required positioning information, and the main control machine resolves each section of concrete position of the dragging cables. The invention adopts the hydroacoustic positioning of an optimized acoustic array and combines a GPS drogue, the compass and the bathometer to position a plurality of cables. The method comprises the following steps: firstly, determining the geodetic coordinates of the front end and the back end of each dragging cable by a GPS; measuring the depth information of each section of the draggingcables by the bathometer, resolving the transverse and longitudinal coordinates of each section on the dragging cables relative to the navigation direction of the dragging ship by acoustic positioning primarily and retaining the value of the transverse coordinates; and recalculating the longitudinal coordinates of each section on the dragging cables by the value of the transverse coordinates obtained by compass data and acoustic positioning.

The invention provides a radio-hydroacoustic remote control system and a radio-hydroacoustic remote control method. The system comprises a ship-borne display and control platform, a radio communication base station, a water surface repeater station and an underwater responder, wherein the ship-borne display and control platform consists of a computer provided with operational software; the radio communication base station comprises a radio station and a universal serial bus (USB) data communication interface; the water surface repeater station comprises a radio station, a hydroacoustic emitting device and a hydroacoustic receiving device; and the underwater responder comprises a hydroacoustic emitting device and a hydroacoustic receiving device. In the system, a radio communication mechanism and a hydroacoustic communication mechanism are combined to establish an acoustic-electric integrated hybrid communication system; in the hydroacoustic communication, an encoding mode of FSK is adopted, a protective time slot is inserted between two adjacent code elements and a confirmation code element and a verification code element are established in a code block, so that the anti-multipath and reverberation capabilities of the system are improved; and inquire response and autonomous inquiry are combined, so that high-reliability half-duplex communication can be realized.

The invention discloses a method and a device of remote uderwater acoustic communication. The device comprises more than one underwater communication nodes and more than one abovewater communication buoys which are responsible for communication with more than one underwater communication nodes within a set distance range through an underwater acoustic channel; and the communication connection is carried out between the abovewater communication buoys through a land wireless channel. In the method, the multi-frequency band combination is adopted to sent data in parallel, and the remote communication is realized by uniting the communication buoys; in the remote communication, a three-time handshake protocol in the carrier sense multiple access (CSMA) needs not to be used in the communicationbetween the underwater communication nodes and the buoys, while a channel can be directly monitored in a full frequency range; the data are synchronously sent to the abovewater communication buoys inparallel on each subchannel on the monitored idle channel by utilizing a frequency modulation method; and the data is transmitted by the abovewater communication buoys through a radio wave manner. Bythe method and device provided by the invention, one-time successful transmission probability of the two parties of the communication can be improved, and the anti-interference performance of a system is enhanced.

The invention relates to an apparatus and method for the in-situ real-time observation of submarine sand waves. The apparatus includes an observation system and auxiliary devices. The auxiliary devices comprise an auxiliary ship and a hoisting device; the observation system includes a gravity anchor, a fiber grating floating earth weight sensor, a Kevlar cable, an underwater acoustic releaser group, a lower floating ball bracket, a wave and tide gauge, an upper floating ball bracket, an MRU three-dimensional attitude sensor, a satellite communication machine, an imaging sonar, a solar cell anda main floating body. The principle of the apparatus and the method is characterized in that submarine pressure change caused by the migration of the submarine sand waves is observed, the time interval, elevation and wavelength data of two adjacent extreme submarine pressures are analyzed, and the migration rate of the submarine sand waves is calculated. The method includes the following steps: selection of an observation point and a deployment time, system deployment, recovery, and data processing. The apparatus and the method provide a new idea for the in-situ real-time observation of the submarine sand waves, have the characteristics of simple and easy device, long in-situ real-time measurement period and wide applicable water range, and can realize the in-situ real-time long-term observation of the migration of the submarine sand waves.

The invention provides small-sized underwater robot combined navigation system and navigation method. The combined navigation system comprises an embedded navigation processor, a pressure-resistant global position system (GPS), a micro attitude sensor, a speedometer, a depth meter and underwater acoustic communication equipment. When an underwater robot carrier is underwater and after the combined navigation system is electrified, the navigation system autonomously runs, a relay is controlled through an input / output (IO) channel of an analog / digital (AD) board to open the sensor for performing data acquisition so as to acquire an initial navigation position, a magnetic declination is calculated according to a magnetic declination database, and planned navigation position correcting instruction information is received for navigation position calculation so as to acquire longitude and latitude position information of an underwater robot. The system has small volume, light weight and lowcost, is favorable for the miniaturization of an underwater navigation system, and can be applied to small-sized underwater robots for underwater observation and detection, which require small size and light weight.

The invention discloses a communication buoy for underwater acoustic positioning and a networking thereof. The communication buoy is connected with a comprehensive processing display control system, and comprises a buoy body, a underwater sound communication machine, a positioning system and a radio communication system; the buoy body provides water surface buoyancy support for the communication buoy; the positioning system and the radio communication system are located at the upper portion of the buoy body, and the positioning system is used for providing position information for the buoy; the radio communication system is used for sending data received by the underwater sound communication device to the comprehensive processing display control system; the radio communication system is further used for receiving a remote control command sent by the comprehensive processing display control system in real time, and sending the remote control command to the underwater sound communicationmachine; the underwater sound communication machine is located on the lower portion of the buoy body for receiving information transmitted by a underwater vehicle and transmitting the remote controlcommand to the underwater vehicle. The invention also provides the communication buoy networking for the underwater acoustic positioning, and the networking comprises at least three communication buoys for the underwater acoustic positioning.

The invention discloses a deep-sea floor pore water pressure long-term observation automatic laying system and a deep-sea floor pore water pressure long-term observation automatic laying method. The system comprises an automatic lifting pore pressure meter, a underwater acoustic / long wave communicator, a ship-borne controller and a laying apparatus; the automatic lifting pore pressure meter orderly comprises a lower drill, a balance weight, a master control cabin, a floating body material, an upper drill and a protective rest from bottom to top; the underwater acoustic / long wave communicator and the ship-borne controller are used for controlling the automatic lifting pore pressure meter. A laying bracket and the automatic lifting pore pressure are sent into the seabed surface through a hook while laying; the lower drill begins drilling hole to enter sediment, and the stops running after arriving a set depth; and then the hook is packed up through a cable to finish the laying. When the system is used for recycling, a releaser is started through the emission of a control signal, parts of the automatic lifting pore pressure meter except the lower drill and the balance weight thereof are separated so that the automatic lifting pore pressure meter is floated, and recycled. The repeated laying-recycling of a complex deep-sea instrument is avoided, the working efficiency is improved, the research cost is lowered, and the artificial disturbance on the field search environment in the laying-recycling process is avoided.

The invention discloses an array-type ocean acoustical signal measurement system. Multiple single channel ocean acoustical signal measurement instruments (NTD) are alternatively fixed on a plastic-wrapped steel cable. Two ends of the plastic-wrapped steel cable are conducted with seawater. A floating body at an upper end of the plastic-wrapping steel cable and a lead fish at a lower end of the plastic-wrapping steel cable are in a vertical state in the ocean. Each NTD is internally provided with a hydrophone and a temperature and salinity sensor. A host computer magnet ring on the plastic-wrapping steel cable, a node magnet ring of each NTD, the plastic-wrapping steel cable and the sea water form a coupling circuit. The NTDs obtain acoustical signals and temperature and depth information which are transmitted to an instrument cabin in the floating body through the coupling circuits and which are sent to a ground reception station via a Beidou all-in-one machine arranged on the floating body. The array-type ocean acoustical signal measurement system provided by the invention can synchronously obtain ocean acoustical signals at different depths according to needs, provides accurate basic data for the research on ocean acoustical environments, and has a wide application prospect.

The invention relates to an ultra short base line underwater target positioning method based on broadband signal time delay detection, which is particular applicable to ultra short base line positioning and parameter underwater sound remote telemetering of an underwater target, for example, a transponder, and belongs to the technical field of underwater target positioning. The characteristic is that the target positioning method adopts an answer mode to carry out target positioning, a platform or an onboard device transmits an inquiring signal at first, a transponder arranged on an underwater target answers correspondingly, the platform or the onboard device receives an answering signal and solves the position of the transponder underwater. According to the method, a spread spectrum technology is adopted to design the inquiring signal and the answering signal, and high-precision positioning of the underwater target (the transponder) is realized. In addition, ultra short base line underwater target positioning method also has functions of telemetering information such as the depth, the attitude of the transponder, the water temperature of a place where the transponder is located, battery voltage of the transponder and the like and remotely controlling the sound source level of the transponder.

The invention discloses an underwater acoustic communication method for simulating a dolphin whistle signal via segmented LFM signals. According to the property that the frequency of the dolphin whistle signal changes with time, a plurality of LFM signals are segmented and combined to simulate the dolphin whistle signal, and a BOK method is used for achieving information modulation on the LFM signals to achieve bionic underwater acoustic communication modulation based on the dolphin whistle signal and the LFM signals. The central frequency and modulation frequency of each segment of LFM signals in balanced receiving data are estimated at a receiving end and are demodulated according to a dolphin whistle signal sample adopted during modulation to obtain demodulation information. The underwater acoustic communication method for simulating dolphin whistle signal via segmented LFM signals can be used for achieving bionic simulate underwater acoustic communication with high reality through a single linear frequency modulated signal and enhancing the communication imperceptibility and practicability.