CN112362902B - Doppler current profiler with self-adaptive intelligent current measurement - Google Patents
Doppler current profiler with self-adaptive intelligent current measurement Download PDFInfo
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- CN112362902B CN112362902B CN202011456373.1A CN202011456373A CN112362902B CN 112362902 B CN112362902 B CN 112362902B CN 202011456373 A CN202011456373 A CN 202011456373A CN 112362902 B CN112362902 B CN 112362902B
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- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
- G01P5/24—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting acoustical wave
- G01P5/241—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting acoustical wave by using reflection of acoustical waves, i.e. Doppler-effect
- G01P5/244—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting acoustical wave by using reflection of acoustical waves, i.e. Doppler-effect involving pulsed waves
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Abstract
The invention discloses a Doppler current profiler with self-adaptive intelligent current measurement. The device comprises a first processing module, a second processing module, a transmitter module, a receiving and sending combined energy-replacing device and an AD sampling module, wherein the first processing module is used for setting a measuring mode and a measuring parameter corresponding to the preliminarily acquired water body environment information and matching the measuring mode and the measuring parameter according to the preliminarily acquired water body environment information. According to the invention, the most suitable flow measurement method is automatically matched through the initially acquired environment information, so that the trouble of manually setting a working mode is avoided, the limitation of the navigation ADCP in different hydrological environments is broken through, the flow measurement is carried out in a shallow water environment by using a pulse coherent method, the flow measurement is carried out in a deep water environment by using a broadband method, and the flow measurement method combining two measurement modes is used at a medium water level, so that the method not only can be better suitable for various hydrological environments, but also can further expand the measured water profile, reduce the estimation area and improve the measurement precision.
Description
Technical Field
The invention relates to the technical field of Doppler current profilers with self-adaptive intelligent current measurement, in particular to a Doppler current profiler with self-adaptive intelligent current measurement.
Background
The ADCP (acoustic Doppler current profiler) is a device developed based on the acoustic Doppler principle and used for measuring the flow velocity of a water body. The direct measurement of ADCP is the radial velocity component in the direction of the sound beam, and usually the depth measured from the first layer of ADCP is WF + WS/2, where WF is the blind area of ADCP and WS is the thickness of the element layer of ADCP. For ADCP using broadband current surveying, WS has certain limitations, because the layer thickness depends mainly on the pulse width of the broadband signal, and the flow velocity for the shallow water depth cannot be measured by using broadband current surveying. The pulse coherent measurement mode utilizes coherent pulse train signals to transmit, receive and process, greatly reduces the pulse width for transmitting signals, and the speed measurement performance of the coherent measurement mode is not determined by a single pulse width any more, so the pulse width can only take a few carrier cycles, and compared with a broadband measurement mode, the depth unit layer thickness is greatly reduced. However, for the pulse coherent flow measurement method, the phase change between a plurality of continuous echoes at the same depth is measured, the flow measurement range of the pulse coherence depends on the time interval between coherent pulse trains, and if the interval is too long, the change of the movement of the scatterer in water is large, the correlation between the continuous echoes cannot be ensured.
For the underway ADCP, it is necessary to adapt to various water depths for profile measurement, and the current ADCP always uses a single measurement method, sacrifices a part of the profile not to be directly measured, and calculates the rest by estimation, thus losing part of the accuracy.
From the above description, it is important to design an adaptive hydrological environment intelligent matching measurement method, an ADCP having both high-precision shallow water flow measurement and deep water flow measurement functions. Therefore, the wrong estimation of a user to a strange hydrological environment is avoided, more water flow profiles can be covered through a proper measuring mode, and accurate measurement can be carried out in both a shallow water low-flow-rate environment and a deep water high-flow-rate environment.
Disclosure of Invention
The invention aims to provide a Doppler current profiler with self-adaptive intelligent current measurement aiming at the defects in the prior art.
In order to achieve the above object, the present invention provides a doppler current profiler with adaptive intelligent flow measurement, comprising:
the first processing module is used for setting a measuring mode and a measuring parameter corresponding to the preliminarily acquired water body environment information, and matching the measuring mode and the measuring parameter according to the currently preliminarily acquired water body environment information, wherein the water body environment information comprises the depth, the flow velocity, the sand content and the signal-to-noise ratio of the water body;
the second processing module is used for being connected with the first processing module, receiving the measurement mode and the measurement parameters sent by the first processing module and modulating the PWM wave control signals corresponding to the water body detection signals according to the measurement mode and the measurement parameters;
the transmitter module is used for being connected with the second processing module so as to receive the PWM wave control signal issued by the second processing module and convert the PWM wave control signal into a voltage control signal;
the receiving and combining displacement energy converter is connected with the transmitter module so as to send out a water body detection signal according to the voltage control signal and acquire water body environment data by receiving the returned water body detection signal;
and the AD sampling module is connected with the receiving and transmitting combined energy-replacing device and the second processing module respectively to send the water body environment data to the second processing module after analog-to-digital conversion processing, and the second processing module further sends the water body environment data to the first processing module so that the first processing module analyzes the final water body environment information according to the water body environment data.
Further, first processing module is used for issuing preliminary measurement instruction to with preliminary measurement instruction send to second processing module, second processing module sends preliminary measurement instruction to the transmitter module, the transmitter module closes the replacement can ware according to preliminary measurement instruction control receiving and dispatching and sends the preliminary measurement signal of water, first processing module closes the degree of depth and the velocity of flow that the signal that returns is received to the transducer and tentatively acquires current water based on receiving and dispatching.
Further, the measurement method includes:
when the depth of the water body obtained in the initial step is lower than a shallow water threshold and the flow velocity is lower than a flow velocity threshold, matching a pulse coherent flow measurement mode;
when the depth of the water body obtained in the initial step is lower than a shallow water threshold and the flow velocity is higher than a flow velocity threshold or the depth of the water body obtained in the initial step is higher than a deep water threshold, matching a broadband flow measurement mode;
and when the depth of the water body obtained in the initial step is between the shallow water threshold and the deep water threshold, matching a mode of pulse coherent flow measurement and broadband flow measurement.
Further, the shallow water threshold is 1m; the deepwater threshold is 2m; the flow velocity threshold is 1m/s.
Further, the measurement parameter includes a layer thickness;
for the primarily obtained water body with the depth less than 1m, the layer thickness adopted by the pulse coherent flow measurement mode is 0.1m;
for the primarily obtained water body with the depth of 1m to 2m, the sound wave signal with the layer thickness of 0.1m is adopted in the pulse coherent flow measurement mode, and the layer thickness of 0.4m is adopted in the broadband flow measurement mode;
for the water body with the depth of 2m to 15m obtained preliminarily, if the signal to noise ratio is more than 10dB, the layer thickness adopted by the broadband flow measurement mode is 0.4m, and if the signal to noise ratio is less than 10dB, the layer thickness adopted by the broadband flow measurement mode is 0.8m;
for the water body with the depth of more than 15m obtained preliminarily, if the signal-to-noise ratio is more than 10dB, the layer thickness adopted by the broadband flow measurement mode is 0.8m, and if the signal-to-noise ratio is less than 10dB, the layer thickness adopted by the broadband flow measurement mode is 1.6m.
Further, the water body preliminary measurement signal is a vertical beam.
Further, the first processing module includes a DSP chip.
Further, the second processing module includes an FPGA chip.
Has the advantages that: the initially acquired environmental information is automatically matched with the most suitable flow measuring method, so that the trouble of manually setting a working mode is avoided, the limitation of the navigation ADCP in different hydrological environments is broken through, the flow is measured in a shallow water environment by using a pulse coherent method, the flow is measured in a deep water environment by using a broadband method, and the flow measuring method combining two measuring modes is used at a medium water level. The flow measurement method combining pulse coherence and broadband can be better suitable for various hydrological environments, the measured water profile can be further enlarged, the estimation area is reduced, and the measurement precision is improved.
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Figure 1 is a schematic block diagram of a doppler flow profiler with adaptive intelligent flow measurement.
Detailed Description
The present invention will be further illustrated with reference to the accompanying drawings and specific examples, which are carried out on the premise of the technical solution of the present invention, and it should be understood that these examples are only for illustrating the present invention and are not intended to limit the scope of the present invention.
As shown in fig. 1, an embodiment of the present invention provides a doppler flow profiler with adaptive intelligent flow measurement, which includes a first processing module 1, a second processing module 2, a transmitter module 3, a transceiver transducer 4, and an AD sampling module 5.
Wherein the first processing module 1 preferably comprises a DSP chip. The first processing module 1 is configured to set a measurement mode and a measurement parameter corresponding to the water body environment information, match the measurement mode and the measurement parameter according to the preliminarily acquired current water body environment information, and then send the matched measurement mode and the matched measurement parameter to the second processing module 2. The water environment information includes information such as depth, flow velocity, sand content, signal-to-noise ratio, etc. of the water, it should be noted that the preliminarily obtained environment information of the current water may be a rough measurement result by other devices, or a rough measurement result of the profiler.
The second processing module 2 preferably comprises an FPGA chip. The second processing module 2 is used for being connected with the first processing module 1, receiving the measuring mode and the measuring parameters sent by the first processing module 1, and modulating the PWM wave control signals corresponding to the water detection signals according to the measuring mode and the measuring parameters. And then the PWM wave control signal corresponding to the water detection signal is sent to the transmitter module 3.
The transmitter module 3 is used for being connected with the second processing module 2 to receive the PWM wave control signal sent by the second processing module 2, convert the PWM wave control signal into a voltage control signal, and send the converted voltage control signal to the transceiver transducer 4.
The receiving and transmitting combined energy replacing device 4 is used for being connected with the transmitter module 3, voltage control signals output by the transmitter module 3 are loaded to two ends of the receiving and transmitting combined energy converter 4, water body detection signals (sound wave signals) are sent out according to the voltage control signals, the returned water body detection signals (sound wave signals) are received, and the water body environment data in the form of electric signals are obtained through conversion between the sound wave signals and the electric signals.
The AD sampling module 5 is connected with the receiving and transmitting combined transducer 4 and the second processing module 2 respectively, the AD sampling module 5 is used for carrying out analog-to-digital conversion processing on water body environment data in an electric form and sending the water body environment data after the analog-to-digital conversion processing to the second processing module 2, and the second processing module 2 further sends the water body environment data in a digital signal form to the first processing module 1 so that the first processing module 1 can analyze final water body environment information according to the water body environment data. Similarly, the final water environment information also includes environment information such as depth, flow velocity, sand content and signal-to-noise ratio of the water, and compared with the initially acquired environment information of the current water, the accuracy of the final water environment information analyzed by the first processing module 1 is greatly improved.
The degree of depth and the velocity of flow of the current water that preliminary acquireed are preferred to be accomplished by this velocity of flow section plotter, when carrying out preliminary measurement, send out preliminary measurement instruction through first processing module 1, and send preliminary measurement instruction to second processing module 2, second processing module 2 sends preliminary measurement instruction to transmitter module 3, transmitter module 3 closes transducer 4 according to preliminary measurement instruction control receiving and dispatching and sends out the preliminary measurement signal of water, the preliminary measurement signal of water is preferred vertical beam signal, and vertical beam signal downwardly emitting signal, thereby carry out the rough measurement to the water environment. The first processing module 1 preliminarily acquires the depth and the flow velocity of the current water body based on the signals received and returned by the receiving and sending combined transducer 4. Specifically, this signal processing flow is the same with above-mentioned water body environment data processing flow, receive and dispatch and close the preliminary measuring signal (sound wave signal) that can ware 4 received the return, then turn into the preliminary measuring signal of electric form to the preliminary measuring signal of sound wave form received, AD sampling module 5 carries out the analog-to-digital conversion back to preliminary measuring signal, then sends to first processing module 1 through second processing module 2, like this, first processing module 1 can be from the preliminary measuring signal that returns analyzing out the degree of depth and the velocity of flow of the current water body of preliminary acquisition. After the current depth and flow velocity of the water body are obtained preliminarily, subsequent matching measurement modes and measurement parameter processes can be automatically carried out.
The measuring mode of the embodiment of the invention comprises the following steps: and when the depth of the primarily acquired water body is lower than the shallow water threshold and the flow velocity is lower than the flow velocity threshold, matching a pulse coherent flow measurement mode. The pulse coherent flow measurement method has the advantages that the spatial resolution and the time resolution are improved, the speed measurement precision is improved, the thickness of a unit layer is reduced, and the accuracy of a measurement result is obviously improved for a shallow water environment. However, the pulse coherent flow measurement method is limited by the velocity-distance fuzzy formula, and cannot measure the flow in a large water depth environment, because the fuzzy velocity of the measurement is seriously reduced, that is, the measurement cannot be performed in a high flow velocity environment. And when the depth of the initially acquired water body is lower than the shallow water threshold and the flow velocity is higher than the flow velocity threshold or the depth of the initially acquired water body is higher than the deep water threshold, matching a broadband flow measurement mode. The broadband lateral flow method, which uses a transducer to transmit broadband coded pulses for measurement, has the advantage of measuring in a deeper environment, but limits the thickness of the unit layer, since the thickness of the unit layer depends on the width of the transmitted pulses. And when the depth of the water body obtained in the initial step is between the shallow water threshold and the deep water threshold, matching a mode of pulse coherent flow measurement and broadband flow measurement. The measurement method is used for measuring the ADCP, and the effective section occupation ratio during measurement can be effectively improved. Among them, the shallow water threshold is preferably 1m. The deepwater threshold is preferably 2m. The flow rate threshold is preferably 1m/s. The measurement parameters comprise the layer thickness, the layer thickness adopted by the pulse coherent flow measurement mode is preferably 0.1m for the primarily acquired water body with the depth less than 1m, the layer thickness adopted by the pulse coherent flow measurement mode is preferably 0.1m acoustic wave signals for the primarily acquired water body with the depth of 1m to 2m, and the layer thickness adopted by the broadband flow measurement mode is preferably 0.4m. For the water body with the depth of 2m to 15m obtained preliminarily, selecting a corresponding layer thickness by combining the signal-to-noise ratio, for example, when the signal-to-noise ratio is above 10dB, the layer thickness adopted by the broadband flow measurement mode is preferably 0.4m, and if the signal-to-noise ratio is less than 10dB, the layer thickness adopted by the broadband flow measurement mode is preferably 0.8m. For the water body with the depth of more than 15m obtained preliminarily, the corresponding layer thickness is selected by combining the signal-to-noise ratio, for example, when the signal-to-noise ratio is more than 10dB, the layer thickness adopted by the broadband flow measurement mode is preferably 0.8m, and when the signal-to-noise ratio is less than 10dB, the layer thickness adopted by the broadband flow measurement mode is preferably 1.6m.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that other parts not specifically described are within the prior art or common general knowledge to those of ordinary skill in the art. Without departing from the principle of the invention, several improvements and modifications can be made, and these improvements and modifications should also be construed as the scope of the invention.
Claims (5)
1. A doppler flow profiler with adaptive intelligent flow measurement, comprising:
the first processing module is used for setting a measuring mode and a measuring parameter corresponding to the preliminarily acquired water body environment information, and matching the measuring mode and the measuring parameter according to the currently preliminarily acquired water body environment information, wherein the water body environment information comprises the depth, the flow velocity, the sand content and the signal-to-noise ratio of the water body;
the second processing module is used for being connected with the first processing module, receiving the measurement mode and the measurement parameters sent by the first processing module and modulating the PWM wave control signals corresponding to the water body detection signals according to the measurement mode and the measurement parameters;
the transmitter module is used for being connected with the second processing module so as to receive the PWM wave control signal sent by the second processing module and convert the PWM wave control signal into a voltage control signal;
the receiving and combining displacement energy converter is connected with the transmitter module so as to send out a water body detection signal according to the voltage control signal and acquire water body environment data by receiving the returned water body detection signal;
the AD sampling module is respectively connected with the receiving, sending, combining and replacing energy device and the second processing module so as to send the water body environment data to the second processing module after analog-to-digital conversion processing, and the second processing module further sends the water body environment data to the first processing module so that the first processing module can analyze the final water body environment information according to the water body environment data;
the measurement mode comprises the following steps:
when the depth of the water body obtained in the initial step is lower than a shallow water threshold and the flow velocity is lower than a flow velocity threshold, matching a pulse coherent flow measurement mode;
when the depth of the water body obtained in the initial step is lower than a shallow water threshold and the flow velocity is higher than a flow velocity threshold or the depth of the water body obtained in the initial step is higher than a deep water threshold, matching a broadband flow measurement mode;
when the depth of the water body obtained in the initial step is between the shallow water threshold and the deep water threshold, matching a mode of combining pulse coherent flow measurement and broadband flow measurement;
the shallow water threshold is 1m; the deepwater threshold value is 2m; the flow speed threshold value is 1m/s;
the measurement parameter comprises a layer thickness;
for the primarily obtained water body with the depth less than 1m, the layer thickness adopted by the pulse coherent flow measurement mode is 0.1m;
for the primarily obtained water body with the depth of 1m to 2m, the thickness of the sound wave signal adopted by the pulse coherent flow measurement mode is 0.1m, and the thickness of the sound wave signal adopted by the broadband flow measurement mode is 0.4m;
for the water body with the depth of 2m to 15m obtained preliminarily, if the signal to noise ratio is more than 10dB, the layer thickness adopted by the broadband flow measurement mode is 0.4m, and if the signal to noise ratio is less than 10dB, the layer thickness adopted by the broadband flow measurement mode is 0.8m;
for the water body with the depth of more than 15m obtained preliminarily, if the signal-to-noise ratio is more than 10dB, the layer thickness adopted by the broadband flow measurement mode is 0.8m, and if the signal-to-noise ratio is less than 10dB, the layer thickness adopted by the broadband flow measurement mode is 1.6m.
2. The Doppler current profiler with adaptive intelligent flow measurement according to claim 1, wherein the first processing module is configured to issue a preliminary measurement command and send the preliminary measurement command to the second processing module, the second processing module sends the preliminary measurement command to the transmitter module, the transmitter module controls the transceiver displacement transducer to send out a preliminary measurement signal of the water body according to the preliminary measurement command, and the first processing module initially obtains the depth and the flow rate of the current water body based on a signal returned by the transceiver displacement transducer.
3. The doppler flow profiler with adaptive intelligent flow measurement according to claim 2, wherein the water preliminary measurement signal is a vertical beam.
4. The doppler flow profiler with adaptive intelligent flow measurement according to claim 1, wherein the first processing module comprises a DSP chip.
5. The doppler flow profiler with adaptive intelligent flow measurement according to claim 1, wherein the second processing module comprises an FPGA chip.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US5208785A (en) * | 1990-09-26 | 1993-05-04 | Rowe, Deines Instruments Incorporated | Broadband acoustic doppler current profiler |
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| DE69126040T2 (en) * | 1990-09-26 | 1998-01-02 | Rowe, Deines Instruments Inc., San Diego, Calif. | ACOUSTIC FLOW PROFILE KNIFE WITH LARGE DOPPLER BANDWIDTH |
| US7539082B2 (en) * | 2006-09-28 | 2009-05-26 | Teledyne Rd Instruments, Inc. | System and method for acoustic Doppler velocity processing with a phased array transducer including using a wide bandwidth pulse transmission to resolve ambiguity in a narrow bandwidth velocity estimate |
| US9404744B2 (en) * | 2014-02-07 | 2016-08-02 | Teledyne Instruments, Inc. | System and method for a handheld current profiler |
| CN104913768B (en) * | 2015-06-25 | 2018-08-28 | 江苏中海达海洋信息技术有限公司 | The adjusting method of the adaptive dynamic adjusting system of multibeam echosounder |
| CN105021843A (en) * | 2015-07-28 | 2015-11-04 | 江苏中海达海洋信息技术有限公司 | 600kHZ broadband acoustics Doppler current profiler and realization method |
| WO2020097390A1 (en) * | 2018-11-07 | 2020-05-14 | Rowe Technologies, Inc. | Horizontal acoustic sediment and current profiler apparatus and methods |
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| US5208785A (en) * | 1990-09-26 | 1993-05-04 | Rowe, Deines Instruments Incorporated | Broadband acoustic doppler current profiler |
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