89 results about "Acoustic Doppler current profiler" patented technology

The invention discloses an ocean submerged buoy system. In the system, buoys are connected with an underwater winch through a communication mooring cable; a plurality of profile measuring instruments are equidistantly arranged at the part of the communication mooring cable between the buoys and the underwater winch, which is adjacent to the buoys; the underwater winch is fixed on a main buoy body; a target detecting system and an ADCP (acoustic Doppler current profiler) are both arranged on the main buoy body; an anchor mooring mechanism comprises a glass floating ball, a response releaser and a ballast anchor which are connected in series through anchor chains; a control center controls the buoy system to regularly float out of the ocean surface and dive into the ocean; the target detecting system detects movable targets; when a movable target enters into a preset range, the control center controls the buoy system to dive into the ocean; and when floating out of the ocean surface, the buoys transmit various received data to a ground shore station. By the ocean submerged buoy system disclosed by the invention, the ocean detected data are transmitted in real time; and the influencestormy waves and other factors on the service life of the buoys is avoided.

The invention discloses an observation system and determining method for the resuspension quantity of deep-sea internal waves to seafloor sediments. The observation system includes a seafloor observation platform, a cable and an anchoring tethered weight. The seafloor observation platform is equipped with an acoustic releaser, a single-point ocean current meter, a turbidimeter, a high-precision conductivity-temperature-depth instrument and a sediment capture device, and the cable is equipped with a main floating body and a sub floating body; a part, located at the middle of the cable, of the main floating body is equipped with an acoustic doppler current profiler; the sub floating body is provided with the turbidimeter and the high-precision conductivity-temperature-depth instrument; the anchoring tethered weight is a gravity anchor with a square-shaped clamping groove and a fixed ring. The determination method includes the steps: calibrating the instruments indoor, placing and recovering the observation system by an auxiliary ship, reading the data of the observation instrument and analyzing the composition of captured suspended matters, and determining the resuspension quantity of the internal waves to the sediments. The observation system can be placed on the deep sea bottom safely and steadily, and can observe the full-water-depth marine dynamic environment parameters fromthe seafloor to the sea surface, and determines the resuspension quantity of the internal waves to the sediments.

The invention provides a method for fusing ocean current observation data of an unmanned undersea vehicle (UUV), which comprises the following steps of: 1, obtaining ocean current profile data, when the UUV underwater navigates at a certain depth, obtaining an ocean current profile with a certain water layer thickness at the upper part or lower part of the UUV; 2, filtering the ocean current profile data, filtering the obtained ocean current original data, eliminating a wild value, carrying out smooth correction on a measured random error; 3, carrying out time registering on the ocean current profile data, reducing asynchronous data into synchronous data under the same time moment; and 4, reducing position information of the UUV, starting from one known coordinate position of the UUV to reduce a coordinate position of the next time according to the navigation direction, the navigation speed and the navigation time of the UUV at the coordinate position; and 5, fusing the ocean current profile data, converting longitude and latitude position information obtained from the reduction of the position information into ASCII (American Standard Code For Information Interchange) codes, and inserting into corresponding positions of an ADCP (Acoustic Doppler Current Profiler) data packet. According to the invention, accurate and complete ocean current profile information can be obtained under a geodetic coordinate system.

The invention relates to a flow field data correction method for an acoustic Doppler flow velocity profiler. The acoustic Doppler flow velocity profiler adopts an acoustic transducer serving as a transducer, acoustic pulses emitted by the acoustic transducer generate scatter echoes through scatterers in unit layers in different water depths, and the scatter echoes are received by the acoustic transducer and analyzed and processed to obtain a radial water velocity. The flow field data correction method for the acoustic Doppler flow velocity profiler is characterized in that the multilayer flow velocity fitting type flow field data correction method is adopted for wild value elimination of radial flow velocity data of each wave beam to realize polynomial fitting, abnormal values of the radial flow velocity are eliminated while changing curves of the radial flow velocity along with depth are smoothened, and accurate flow velocity information under an instrument coordinate system is further acquired.

The invention discloses a timed satellite communication submerged buoy, which comprises a plastic covered steel cable in vertical arrangement, wherein a first sensing coupling temperature-salinity chain, a second sensing coupling temperature-salinity chain, a main floating body and a deep ocean current and temperature-salinity measuring unit are arranged on the plastic covered steel cable; an acoustic Doppler current profiler, satellite communication buoys, a timed release device and a data and control electronic cabin are arranged on the main floating body; and submerged buoy measuring instruments are connected with the data and control electronic cabin through cables. The timed satellite communication submerged buoy has the advantages that one or a plurality of satellite communication buoys are arranged on the main floating body of the submerged buoy; observational data of submerged buoy instruments are transmitted to the satellite communication buoys under water through cables or in a cableless mode; when the set time is reached, the satellite communication buoys automatically float up to the water surface; and stored data is sent to a shore station through satellites, so that ocean observational data can be enabled to be obtained in time; the work state of the submerged buoy can be known; and huge help is realized on the reliability, the stability and the like of the submerged buoy.

The invention provides a river channel water flow real-time online monitoring method and device. A boat-mounted flow rate collection device is used for collecting flow rate data in the vertical direction of a river channel and transmitting the flow rate data to a GPRS wireless network, the flow rate data in the horizontal direction of the river channel is collected by a horizontal type flow rate collection device and transmitted to the GPRS wireless network by the horizontal type flow rate collection device, the water level data of the river channel is collected by a water level collection device and transmitted to the GPRS wireless network by the water level collection device, the GPRS wireless network is connected with the Internet network and transmits the flow rate data in the verticaldirection of the river channel, the flow rate data in the horizontal direction of the river channel and the water level data of the river channel to a central station through the Internet network, and analysis and storage are conducted on the received data by the central station, so that river channel water flow real-time online monitoring is achieved, obtained data information is processed in real time simultaneously, and the current river channel water flow data is obtained by conducting real time analysis and computing.

The invention relates to a lowered acoustic Doppler current profiler (LADCP) with an acoustic telemonitoring function, wherein, an underwater acoustic communication technology is adopted to transmit the data of depth and height from the bottom of an LADCP suspension system in real time to a water surface control unit by code and decode with code division multiple access for monitoring the positionin water of the suspension system in real time. The lowered acoustic Doppler current profiler comprises an underwater main body part and a water surface telemonitoring part; a master LADCP is internally provided with a communication encoding module, wherein, the master LADCP circularly measures a current profile at fixed time and obtains the height to the bottom according a bottom tracking resultand a depth value by a pressure sensor at the same time; the communication encoding module carries out CDMA code modulation on the height value and the depth value and then outputs the values by a high-speed DA every 1-10s or so, preferably 5s, and emits out the values through a watertight cable and an underwater acoustic communication transmitter; and the underwater acoustic communication transmitter at a water surface telemonitoring part carries out amplification, automatic gain control and filtration on the received signal and then sends the signal to a deck unit through a Kevlar cable.

The invention discloses a hydrometric station cableway type flow velocity automatic measurement device. The hydrometric station cableway type flow velocity automatic measurement device comprises a plurality of fixing cables, wherein top ends of the fixing cables are hung on a cableway system, and an instrument container with an acoustic doppler current profiler (ADCP) controller arranged inside is connected with lower ends of the fixing cables. A flow guiding structure is fixed below the instrument container through a connecting rod, and an ADCP which is electrically connected with the ADCP controller is fixed at the bottom end of the flow guiding structure. The ADCP controller communicates with a control system installed in a control chamber of a hydrometric station, and a motor of the cableway system is controlled by the control system. The hydrometric station cableway type flow velocity automatic measurement device is high in reliability, the problem that an existing device needs to be operated by a test worker on the spot is solved, and the aim of being guarded by nobody is achieved.

The invention discloses a multi-scale synchronous observation subsurface buoy for an ocean dynamic environment. The multi-scale synchronous observation subsurface buoy comprises an vertically arranged rope; the upper portion of the rope is provided with a first temperature-salinity chain, a second temperature-salinity chain, a micro-scale fixed point turbulence meter and a main floater. Both the first temperature-salinity chain and the second temperature-salinity chain comprise thermometers, bathythermographs and conductivity-temperature-depth systems. The main floater is located between the first temperature-salinity chain and the second temperature salinity chain. An acoustic Doppler velocity section plotter is installed on the main floater. The middle portion of the rope is provided with a reciprocation micro-scale turbulence section plotter. The reciprocation micro-scale turbulence section plotter is provided with a conductivity-temperature-depth system, a current meter, a shearing probe for observing the turbulence, and a fast temperature probe. The lower portion of the rope is provided with a deep ocean current and temperature-salinity measuring unit; and the deep ocean current and temperature-salinity measuring unit comprises a conductivity-temperature-depth system and a current meter. The multi-scale synchronous observation subsurface buoy can achieve the long-term continuous multi-scale synchronous observation of ocean dynamic environment parameters in macro-scales such as full-depth temperature, salinity and flow field, and micro-scales such as the turbulence.

The invention discloses a 600kHZ broadband acoustics Doppler current profiler and a realization method, wherein the current profiler comprises an emission module, a reception module, a data storage module, a display-and-control computer, a sensor module, a power supply module, and a main and secondary processor that are interconnected. According to the broadband acoustics Doppler current profiler BBADCP provided in the invention, a sinusoidal signal coded by M sequence is used as the emission signal, therefore a higher distance-speed precision, a long detection distance and a short speed average time are provided; a frequency measurement method that combines multiple correlation frequency measurement and delay frequency measurement is employed, therefore the high precision of correlation frequency measurement is provided, and the problem of speed fuzzy of correlation frequency measurement is solved; the acoustic velocity is calculated at real time based on data like temperature and pressure, and the acoustic velocity is compensated at real time, therefore the flow measurement precision is improved.

The invention relates to a method for acquiring radial direction water velocity in an acoustic Doppler current profiler. The acoustic Doppler current profiler adopts an acoustic wave transducer as a sensor, an emitted acoustic impulse generates a scatter echo through an irregular scatterer in a water body, the acoustic wave transducer receives the scatter echo, and the radial direction water velocity is acquired through analysis. The method is characterized by comprising the following steps: firstly, setting a search scope and a count of radial direction water velocity according to the direction and degree of urgency of water flow in measurement environment; and secondly, designing a matching signal corresponding to radial direction velocity of each search point, carrying out matched filtering operation on the matching signal corresponding to each radial direction velocity and an echo signal received by the acoustic wave transducer, and searching a matched filtering result, wherein the radial direction velocity corresponding to a maximum value of the matched filtering result is the radial direction velocity to be measured.

The invention relates to a whole-bottom-material bottom-resting seabed submarine buoy and a measuring system thereof, and belongs to the field of submarine buoys. The submarine buoy comprises a main frame, a counterweight base, a floating body, a pressure shell, a release holder, an acoustic release, a power module, a controller, a radio beacon, an underwater acoustic communication machine, a conductivity-temperature-depth measuring meter, a deep water acoustic Doppler current profiler, a current meter and a gas sensor, wherein the main frame is provided with a plurality of supporting feet, and the counterweight base is provided with a plurality of supporting foot holes; the supporting feet are sleeved with springs and provided with limiting mechanisms, an anchor chain assembly is installed on the counterweight base, and the free end of the anchor chain assembly is connected in the release hook of the acoustic releaser; when the support feet are located in the supporting foot holes, the upper ends of the springs abut against the limiting mechanisms, the lower ends of the springs abut against the counterweight base, and the springs are in a compression state. When the release hook of the acoustic releaser is opened, and the springs provide an upward elasticity for helping the main frame to separate from the seabed mud where the main frame deeply falls, so that the recovery of the detecting instruments on the submarine buoy is achieved.

The invention relates to a method for inverting concentration of suspended particulate matters based on acoustics; the method comprises: receiving a back-scattering signal of an underwater scattering body to obtain echo strength by using an acoustic Doppler current profiler; according to a sonic equation, correcting the echo strength by considering acoustic wave geometric attenuation and absorptive attenuation to obtain volume back-scattering strength; according to the corrected volume back-scattering strength, finally inverting the concentration of suspended particulate matters with high time-space resolution in accordance with Rayleigh scattering principle. The method can provide precise concentration of suspended particulate matters.

A clamp-on type acoustic Doppler current profiler eliminates, among ultrasound echoes caused by two measurement lines of a longitudinal wave and a shear wave propagating in a piping, the ultrasound echo based on the longitudinal wave, thereby providing the measurement of a flow rate profile and / or a flow rate with a higher accuracy. The profiler includes a wedge mounted to the piping. The wedge includes an inclined surface at which an ultrasonic transducer can be mounted. The inclination is such that the ultrasound transducer receives only the ultrasound echo from the reflection of a shear wave component off the reflectors in the fluid.

Underwater vehicles may fix their position from GPS at the surface of the water and use bottom track for dead reckoning once it has descended to within tracking range of the bottom of a body of water. This disclosure describes a method and system for navigation through the water through depths where GPS is not available using current profiles from sonar systems including acoustic Doppler current profilers (ADCP). This extrapolation of earth referenced current profiles can provide a way to estimate vehicle motion below the surface before the vehicle reaches the bottom. Once bottom track is achieved, the corrected reference for vehicle motion improves the vehicle position estimate. A Kalman filter updates vehicle position and current profile estimates during descent, and the bottom track when the bottom comes within range to enable navigation of underwater vehicles.

The invention relates to an FPGA-based acoustic doppler current profiler signal processing method. The method comprises the steps: 1. performing system initialization; 2. emitting a pulse signal, acquiring a wave beam output signal after emitting the pulse signal, storing a digital signal in a DDR2 memory; 3. reading the digital signal data from the DDR2 memory, performing orthogonal base band modulation processing and duplex downsampling filtering processing on the digital signal data, and storing the result in the DDR2 memory; 4. reading the data after the duplex downsampling filtering processing from the DDR2 memory, and performing multiple correlation operation; 5. acquiring temperature, pressure and other signals by a low velocity AD circuit, and calculating the acoustic velocity in the current water body, and then reading the data after the multiple correlation operation to calculate the flow velocity and the echo energy; and 6. storing the result data in a TF card, and sending the data to a host computer to process and display. The invention also provides an FPGA-based acoustic doppler current profiler signal processing system. The FPGA-based acoustic doppler current profiler signal processing system has the advantages of being simple in structure, being low in power consumption, being low in cost, being small in volume, and being good in real-time.

The invention discloses an observation bracket for an acoustic Doppler current profiler, and belongs to a matched device for the acoustic Doppler current profiler. The observation bracket comprises a bracket body, wherein a mounting plate is fixedly arranged at the bottom of the bracket body; a first fixed plate and a second fixed plate are further arranged on the bracket body; the second fixed plate is positioned on the lower part of the first fixed plate; a protective device is further arranged outside the bracket body. According to the observation bracket, the protective device is fixedly connected with the bracket body, so that the observation bracket is more stable when being used, and is difficult to incline by water flow impact, survey ship navigation or the like, influence on work can be eliminated even through the observation bracket encounters aquatic plants, bamboo poles and ropes for cultivation, anchor ropes and the like, the accuracy of measurement data of the acoustic Doppler current profiler is ensured, and the profiler is more difficult to damage by the scouring of water flow; in addition, the observation bracket for the acoustic Doppler current profiler is simple in structure and wide in application range, and can be matched with various types of acoustic Doppler current profilers for use.

The invention relates to the technical field of oceanographic observation and especially relates to a current surveying method by means of an acoustic Doppler current meter. The method comprises following steps: the current meter calculates the beam bottom depth and the beam bottom speed according to four beam echo signals obtained by a transducer in combination with the current meter set parameter information, gestures, temperature, pressure information and sound velocity information; generates a three-dimensional vector speed and then performs coordinate transformation; smoothes and filters current surveying data and finally outputs current surveying results. According to the method, acoustic Doppler frequency shift principles are adopted for measuring current velocity; ocean dynamic environment parameters and current data can be observed for a long time by deploying acoustic Doppler current meters in submerged buoy systems to obtain ocean dynamic environment parameters such as temperature, pressure, current velocity and flow direction in the deploying sea areas; the acoustic Doppler current meter has a direct reading work mode and a self-contained work mode, and has high current surveying accuracy and flexible operation.

The invention discloses a drifting detection underwater robot device and a control method, and belongs to the technical field of detection underwater robots. A robot main body is of a torpedo-shaped structure; hydrologic detection equipment ADCP (Acoustic Doppler Current Profiler), ranging sonar and an emergency load rejection device are carried at the fore body of a robot; a pressure-resistant cabin is arranged at a middle cabin section; the pressure-resistant cabin is divided into an energy source cabin and a control cabin; two high-energy density lithium batteries are arranged in the energysource cabin and are correspondingly used for supplying power to a power system and a control system; a conformal antenna (comprising Beidou positioning and communication, radio and WiFi), DVL, a depthometer and ranging sonar are carried at the tail section; high-efficiency propellers are arranged on the left side and the right side of the tail of the robot; and vertical channel propeller is arranged at each of the front and rear of the robot. According to the surrounding environment and task instructions of the robot, the effect of selecting to start or close a drifting mode is intelligentlyrealized, so that low-power-consumption, long-voyage and long-time detection monitoring tasks are realized.

The invention discloses a signal processing system of an acoustic Doppler current profiler based on an FPGA (Field Programmable Gate Array). The signal processing system comprises a main processor module, a slave processor module, an echo signal acquisition module, a communication module, a power source module, a control signal output module and a data storage module, wherein the echo signal acquisition module is used for synchronously acquiring echo signals fed back by the current profiler and transmitting the sampled signals to the main processor module; the main processor module is responsible for the realization of a signal processing algorithm and comprises multiple down-sampling filtration, multiple correlation operation and the like; in addition, processed data also need to be stored; the processed data are stored in the data storage module; the slave processor module is used as an auxiliary processing unit and is used for the communication management of power dissipation of the system and partial data; the communication module is used for completing the receiving and dispatching of external data. Aiming at the characteristics of large data volume and algorithm complexity of a processing unit of the acoustic Doppler current profiler, the signal processing system uses the FPGA as a core data processor of the main processor module, so that the timeliness and the accuracy of data processing are ensued. The signal processing system has the advantages of strong expansibility multiple functions and meets the high requirements of the acoustic Doppler current profiler on data operation.

The invention relates to a posture balancing self-control device of a lowered acoustic Doppler current profiler (LADCP), which comprises a frame body, wherein the frame body is at least supported by four struts; brackets with shaft holes are symmetrically arranged in the frame body and one third far away from the top, and a balancing ring is fixed by the other end of a support shaft and provided with two clamping ring shaft holes; clamping rings are fixed at the other end of an inner ring shaft which is inserted into the clamping ring shaft holes; the joint position of the two clamping rings is provided with a bolt, a connecting line of the two clamping ring shaft holes is perpendicular to a connecting line of the two shaft holes, and the LADCP is clamped and fixed by the bolt. Obviously, the invention has reasonable structure and simple process and enables the LADCP to maintain the posture that the direction of an energy converter is perpendicular to the sea level all the time in the working process.

The invention discloses a method and a device for reducing power consumption of a signal processing unit of an acoustic Doppler current profiler. The device comprises a slave processor, a master processor, a power supply module, a communication module, a signal acquisition module, a control signal module and a storage module, wherein the slave processor controls power-on and power-off states of an electrifying module and the master processor of the signal processing unit according to a set working time point. The master processor needing massive data processing works intermittently, and only the slave processor with ultra-low power consumption works in idle time not reaching the set working time point. The slave processor is interrupted and awakened by the master processor, so that the energy-saving effect is realized. According to the invention, in consideration of the characteristics of large data size and discrete data processing time points of the signal processing unit of the acoustic Doppler current profiler, the working time periods of the master and slave processors are sequentially separated so as to guarantee the real time property of data processing. The method and the device have the advantages of effectively controlling heat dissipation, improving work stability and reliability of the signal processing unit and achieving an energy saving effect to enable the acoustic Doppler current profiler to work for a long time with power supply from a mobile battery.

The invention provides an automatic testing method for an acoustic Doppler current profile. The automatic testing method comprises the steps of: step 1) splitting a radiation region of an acoustic wave beam emitted by means of the acoustic Doppler current profile into a plurality of cone scattering flow layer research units having different heights; step 2) emitting an acoustic wave beam by meansof the acoustic Doppler current profile, acquiring the acoustic wave beam in an acoustic coupling manner, and converting the acoustic wave beam into a modulated pulse signal; step 3) simulating and generating scattered echo signals corresponding to flow layers in the radiation region, and converting the scattered echo signals into acoustic pulses for emission; step 4) and utilizing the acoustic Doppler current profile to receive the acoustic pulses emitted in the step 3) in an acoustic coupling manner, calculating to obtain speed numerical values corresponding to the flow layers, comparing thespeed numerical values with a standard value, and further determining the working performance of the acoustic Doppler current profile. The automatic testing method provided by the invention realizesthe high-precision onshore automatic test of the acoustic Doppler current profile.

The invention provides an ad-hoc network marine environment multi-parameter measurement method. A plurality of unmanned platforms are used for carrying marine environment measurement sensors, and a navigation, surveying and mapping integrated system is used in cooperation to realize networking measurement. The navigation, surveying and mapping integrated system runs in a shore-based or mother shipoperation management center and controls and coordinates the plurality of measurement sensors to work. The measurement sensors comprise a multi-beam echo sounder and an acoustic Doppler velocity profiler, and provides marine environment data acquisition. The unmanned platform is formed by integrating a surveying and mapping type hull, an autonomous obstacle avoidance unit and an intelligent control unit, and is used as a mobile platform for measuring networking measurement of the measurement sensors. The navigation and surveying and mapping integrated system is formed by integrating a collaborative management software module, a surveying and mapping operation module and a multi-source multi-platform surveying and mapping data real-time splicing module, and networking operation and data post-processing are realized. The networking measurement method has the characteristics of high measurement efficiency, high platform and sensor compatibility and the high multi-instrument networking observation and multi-source data fusion level.

The invention discloses a method for combined pulse speed measurement for an acoustic Doppler flow rate section plotter. An acoustic wave energy exchanger is adopted by the acoustic Doppler flow rate section plotter to serve as a sensor, scattering echoes are generated by sound wave pulses transmitted by the acoustic Doppler flow rate section plotter through an irregular scattering body in water, and after the scattering echoes are received by the acoustic wave energy exchanger, the radial water flow speed is obtained through analysis and processing. The method is characterized in that combined pulses serve as transmitting signals of the acoustic wave energy exchanger; after echo signals are received by the acoustic wave energy exchanger, the echo signals are multiplied by transmitted combined pulse signals; a result is analyzed through a low-pass filter wave and a following frequency spectrum, and therefore the radial flow speed needing to be measured is obtained.

The invention relates to installation equipment for acquiring ocean current data on a floating platform, in particular to an ADCP (Acoustic Doppler Current Profiler) installation system applied to the floating platform. The ADCP installation system comprises an armored cable, a steel cable sliding rail, a fixed frame and a limiting clamp seat, wherein the limiting clamp seat is arranged on an underwater cross beam of the floating platform and is used for limiting the fixed frame; one end of the steel cable sliding rail is connected with the limiting clamp seat; the other end of the steel cable sliding rail is connected below a deck of the floating platform; the fixed frame can be connected with the steel cable sliding rail in a vertically-sliding manner; an ADCP is arranged in the fixed frame; a probe of the ADCP faces downwards; one end of the armored cable is hung on the fixed frame; the other end of the armored cable is connected with a winch arranged on the floating platform; and the fixed frame is pulled by the winch to vertically move along the steel cable sliding rail. According to the ADCP installation system disclosed by the invention, ADCP equipment can be quickly fixed to the bottom of the floating platform and can be quickly lifted when the repair and the maintenance are required; and the workload of divers and underground robots is reduced and the maintenance cost is reduced.

The invention relates to an experiment device for testing dynamic behaviors of a pipe string in deep water. The device comprises a nitrogen cylinder, a nitrogen pressure reducing valve, a flow meter,a connection pipeline, a micro-pressure sensor, laser velocity measurement sensors, flexible joints, a water insulation pipe string, an acoustic Doppler flow velocity profiler, strain rosettes, a datacollection cable, a display, an ocean wave and current co-creating experiment flume, a pipe string holder, a test pipe string and a mechanical flow meter. The nitrogen cylinder generates high pressure airflow. Pressure of the high pressure airflow is reduced to required pressure through utilization of the nitrogen pressure reducing valve. The strain rosettes collect data that the high pressure airflow results in deformation of the test pipe string. The laser velocity measurement sensor collects integrated deformation of the pipe string. The micro-pressure sensor collects stress in an axial direction of the pipe string. The stress is displayed on the display. The device has the advantages that various occasion situations can be simulated, and the device is safe and reliable, is convenientfor operation and is accurate in measured data.

The invention relates to a method for optimizing and selecting transmitting frequency of an ADCP (acoustic Doppler current profiler) with environmental adaptability. The method comprises the followingsteps: S1, according the mathematic relation among a transducer receiving level in an ADCP transducer receiving level as well as a sound source level, one-way propagation loss, a target intensity level and a background noise level, acquiring a sonar equation of the transducer receiving level as well as the sound source level, the one-way propagation loss, the target intensity level and the background noise level; S2, according to the mathematic relation among transmitting frequency, acoustic diameter of a transmitting transducer, the wavelength of transmitting sound wave and the sound sourcelevel, acquiring a calculation formula of the sound source level; S3, according to the mathematic relation among the measuring distance, the attenuation coefficient of water for the sound wave and theone-way propagation loss, acquiring a calculation formula of the one-way propagation loss; and performing other steps to acquire the transmitting frequency. The echo signal-to-noise ratio of the ADCPby using the method can be increased by at most 20 dB compared with that of the ADCP with fixed transmitting frequency.

The invention provides a device for monitoring seabed shallow sediment erosion resuspension in an internal wave environment. The device comprises a snorkeling system, an observation platform and a supporting system, the snorkeling system comprises a glass floating ball combination, a mooring rope, a subsurface buoy, a Kelvar cable and a limiting cylinder. The observation platform comprises a middle supporting rod, a stabilizing circular ring, a supporting rod, an acoustic Doppler current profiler, a sediment capturer, a circular ring with a hole, an optical backscattering turbidity meter, a battery bin, a conductivity-temperature-depth meter, a supporting plate and an acoustic Doppler velocimetry. The supporting system comprises a buffering device, a vertical supporting rod and a gravity anchor. According to the technical scheme of the invention; the device aims to directly reach the seabed to collect and obtain accurate suspended sediment concentration information on the basis of notdestroying the seabed environment. The influence of the seabed on the internal solitary wave suspended sediments is discussed; and the device is good for evaluating the suspension quantity caused by internal solitary waves and the influence on the seabed deposition process, is good for further predicting the seabed evolution, is good for accurately describing the sediment movement and improving the sediment resuspension quantity prediction level in application, and also provides a new technology and means for sediment resuspension research.

Provided is a method of effectively improving the flow direction measurement precision of an acoustic doppler current profiler (ADCP), relating to an ADCP. The method comprises: firstly, establishing a mathematic model, analyzing the relation between magnetic north angle change and final flow direction change, and obtaining that an angle variable quantity is equal to a flow direction variable quantity when only the magnetic north angle change exists; and based on the above, using a least square method to fit errors of a flow direction influenced by magnetism, and using a fitting coefficient to compensate for ADCP actual measurement flow direction output. Compared with a standard flow direction, the root-mean-square value of the errors of a flow direction influenced by magnetism can be reduced by 70%. The method can effectively compensate for the flow direction error of an ADCP internal magnetic compass caused by environmental magnetic field interference in an azimuth scope of 0-360 DEG, thereby substantially improve flow direction measurement precision in an omnibearing scope, and have engineering guidance value for long-term fixed point flow measurement in sea observation.