CN113109824B - Split beam-based underwater target identification method - Google Patents
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Abstract
The invention belongs to the technical field of marine underwater target identification, and particularly relates to an underwater target identification method based on split beams, which comprises the following steps: transmitting acoustic wave signals with specific frequency and specific bandwidth to a sea area in a form of a 'narrow-band-broadband' wave beam alternating period, transmitting the acoustic wave signals to a marine organism target to be detected in the sea area, generating scattered echo signals, and sequentially reflecting the scattered echo signals to four channel receivers of a four-quadrant split-beam transducer; the signal mixer performs beam splitting processing of narrowband signals on the received digital signals alternately transmitted by the narrowband and the broadband of the four channels to obtain the position of a target to be detected in split beams; meanwhile, the signal synthesizer performs synthesis processing of broadband signals on the received digital signals of the four channels, extracts broadband signals in the digital signals of the four channels, synthesizes the four broadband signals to obtain a single-beam broadband signal, and processes the single-beam broadband signal to obtain the size and biological species of the target to be detected.
Description
Technical Field
The invention belongs to the technical field of marine underwater target identification and acoustic measurement, and particularly relates to an underwater target identification method based on split beams.
Background
In recent years, the damage to the ecological environment of the sea, the river and the like is more and more serious, the fishery resources which are important indexes of the ecological system are seriously exhausted, the fishery and biological resource monitoring of the sea, the inland the lake are one of important key problems of the protection and the ecological restoration of the aquatic organisms, and particularly, the resource quantity, the density and the fish swarm activity state change of the marine organisms such as fishes and the like are important bases for establishing a resource monitoring and evaluating theory and a method. The biological resources are quantitatively monitored and evaluated, the condition of the amount of the fishery resources can be mastered in time, the growth state of the direct index of the water ecological environment is known, and protection measures are timely taken for repairing, so that the sustainable development of the marine fishery resources is ensured.
Acoustic measurement technology is an important method for monitoring and evaluating marine fishery resources, and has been applied to marine fishery resource investigation and evaluation. Due to the fact that the underwater visibility is low in most cases, the optical equipment has a limited working distance due to the fact that the optical equipment is greatly influenced by the attenuation of light in seawater, and the optical equipment is difficult to play a role in monitoring and evaluating fishery resources in large-area ocean, inland and other water areas. From the trend of marine organism resource monitoring technology development, the acoustic technology is a main method for monitoring and evaluating marine organism resources, and compared with the optical monitoring method, although the acoustic technology is not as visual as the optical method, the acoustic technology can meet the requirements of monitoring and evaluating marine organism resources such as oceans, inland rivers and the like in a large area because the propagation distance of the acoustic technology in water is far more than that of the optical method, electromagnetic waves and the like.
At present, scientific fish probes for the evaluation of marine fishery resources are mostly installed on investigation ships, and marine fishery resources such as oceans, lakes and other organisms are investigated and evaluated by adopting a sailing mode. However, with the needs of marine ecological environment monitoring, repairing and protecting, the existing method has errors in the identification of underwater targets, has poor timeliness of navigation investigation data, cannot effectively monitor and evaluate, and cannot perform long-term and real-time fixed monitoring.
Disclosure of Invention
In order to solve the defects in the prior art, the invention provides a split beam-based underwater target identification method, which can realize efficient and fixed monitoring and effective resource assessment on fishery resource quantity in water areas such as oceans, lakes, large-scale aquaculture net cages and the like, and can evaluate the fishery resource quantity in the monitored water areas, time-space distribution, density measurement, species identification and the like, and provides a resource quantity evaluation and species identification method applicable to fishery resource monitoring.
The invention provides a split beam-based underwater target identification method, which comprises the following steps:
the four-quadrant split beam transducer transmits sound wave signals with specific frequency and specific bandwidth to a sea area in a mode of 'narrow-band-broadband' beam alternating period, transmits the sound wave signals to a marine organism target to be detected in the sea area, generates scattered echo signals, and sequentially reflects the scattered echo signals to four channel receivers of the four-quadrant split beam transducer;
each channel receiver sequentially receives echo signals reflected from a target to be detected, performs gain control amplification and AD analog-to-digital conversion on each echo signal to obtain digital signals alternately transmitted by the narrow bands and the wide bands of the four channels, and sends the digital signals alternately transmitted by the narrow bands and the wide bands of the four channels to a signal mixer;
the signal mixer performs beam splitting processing of narrowband signals on the received digital signals alternately transmitted by the narrowband and the broadband of the four channels to obtain the position of a target to be detected in split beams;
meanwhile, the signal synthesizer carries out synthesis processing of broadband signals on the received digital signals of the four channels, extracts broadband signals in the digital signals of the four channels, synthesizes the four broadband signals to obtain a single-beam broadband signal, and processes the single-beam broadband signal to obtain the size and biological species of a target to be detected;
and fusing the positions, the sizes and the types of the targets to be detected in the four split beams to obtain information of the targets to be detected, and completing identification of the targets to be detected.
As one of the improvements of the above technical solutions, the four-quadrant split beam transducer includes:
the circular plane array and a plurality of tap, circular plane array divide into 4 quadrant areas that head and tail are connected, include: a first quadrant region with an upper right of the first channel receiver, a second quadrant region with an upper left of the second channel receiver, a third quadrant region with a lower left of the third channel receiver, and a fourth quadrant region with a lower right of the fourth channel receiver; and the first quadrant area, the second quadrant area, the third quadrant area and the fourth quadrant area are respectively provided with a tap.
As one of the improvements of the above technical solution, P primitives are set in each of the first quadrant, the second quadrant, the third quadrant and the fourth quadrant, where P is determined by the beam width, the conversion efficiency and the side lobe level.
As one of the improvements of the above technical solution, the signal mixer performs beam splitting processing of narrowband signals on the received digital signals alternately transmitted by narrowband and wideband of four channels, so as to obtain the position of the object to be detected in the split beam; the specific process is as follows:
the signal mixer extracts narrow-band signals in the digital signals of the four channels respectively to form four half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a first quadrant area where the first channel receiver is located and a second quadrant area where the second channel receiver is located respectively, and combines the narrow-band signals into upper half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a second quadrant area where the second channel receiver is located and a third quadrant area where the third channel receiver is located respectively, and the narrow-band signals are combined into left half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a third quadrant area where the third channel receiver is located and a fourth quadrant area where the fourth channel receiver is located respectively, and the narrow-band signals are combined into a lower half beam of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a fourth quadrant area where the fourth channel receiver is located and a first quadrant area where the first channel receiver is located respectively, and the narrow-band signals are combined into a right half beam of the split beam array;
determining a vertical deviation angle of a target to be measured through the phase difference between the upper half beam of the split beam array and the lower half beam of the split beam array, and determining a horizontal deviation angle of the target to be measured through the phase difference between the left half beam of the split beam array and the right half beam of the split beam array; and determining the position of the object to be measured in the split beam according to the vertical offset angle and the horizontal offset angle of the object to be measured.
As one of the improvements of the above technical solution, the vertical offset angle of the object to be measured is determined by the phase difference between the upper half beam of the split beam array and the lower half beam of the split beam array, and the horizontal offset angle of the object to be measured is determined by the phase difference between the left half beam of the split beam array and the right half beam of the split beam array; determining the position of the target to be measured in the split beam according to the vertical offset angle and the horizontal offset angle of the target to be measured; the specific process is as follows:
the signals received by the four quadrant array elements of the first quadrant area, the second quadrant area, the third quadrant area and the fourth quadrant area are sequentially X 1 ，X 2 ，X 3 ，X 4
By finding X 1 And X 4 Or X 2 And X 3 Is used to detect the correlation peak R (τ) 0 ) Thus, the phase difference of the array element receiving signals passing through the upper half beam of the split beam array and the lower half beam of the split beam array is obtained, and the phase difference is used as the azimuth angle of the target to be detected, namely the vertical offset angle phi;
by finding X 1 And X 2 Or X 3 And X 4 Is a cross-correlation function R of 1 (τ) detection of correlation peak R 1 (τ 01 ) Thus, the phase difference of the left half wave beam of the split wave beam array and the right half wave beam of the split wave beam array, which are used as the azimuth angle of the target to be measured, namely the horizontal offset angle theta, of the array element receiving signals are obtained;
determining the distance r of an object to be measured:
wherein c is the speed of sound; t is the time of detecting the echo of the target to be detected;
establishing a spherical coordinate system with the center of the split beam array as the origin of coordinates, and taking the position of the object to be measured in the split beam array as the coordinates
And the coordinates are set
Performing coordinate conversion to obtain the position of the object to be measured in a rectangular coordinate system as coordinates (x, y, z);
wherein,,
and taking the position of the object to be measured in the rectangular coordinate system as the position of the object to be measured in the split beam array.
As one of the improvements of the above technical solution, the signal synthesizer performs synthesis processing of broadband signals on the received digital signals of the four channels, extracts broadband signals in the digital signals of the four channels, synthesizes the four broadband signals to obtain a single-beam broadband signal, and processes the single-beam broadband signal to obtain the size and biological species of the target to be detected; the specific process is as follows:
the signal synthesizer extracts broadband signals in the received digital signals of the four channels, and synthesizes the four broadband signals to obtain synthesized broadband signals;
performing time-varying gain compensation on the synthesized broadband signal to compensate the expansion loss and absorption loss of the sound wave propagating in the water, obtaining the real echo energy of the target, and compensating according to the distance to obtain the broadband signal after gain compensation:
x RX ＝x TX +Loss
wherein x is TX Is a synthesized width signal of the transmitted time sequence; x is x RX Receiving a time-series gain-compensated wideband signal;
wherein,,
Loss＝20log R+αR (1)
where Loss is the Loss compensation amount in units of: dB (dB); r is the distance of the object to be measured, unit: rice; alpha is the absorption coefficient of water, unit: dB/m;
and (3) adopting a matched filter and adopting a Fourier transform and inverse Fourier transform method to perform pulse compression processing on the broadband signal after gain compensation to obtain a compressed pulse signal:
x MF ＝F -1 {F(x TX )F(x RX )} (2)
wherein x is MF Is a pulse compressed signal; f (·) is the Fourier transform; f (F) -1 {. The inverse fourier transform;
pulse compression signal x MF The spatial resolution of the pulse compression signal is dependent on the bandwidth of the signal, a signal detection threshold is set according to the marine organism detection condition, peak separation processing is carried out on the pulse compression signal, the initial position of the target to be detected and the target echo width are obtained, and then the size of the target to be detected is estimated;
and obtaining broadband spectrums of echoes of different anatomical structures of the marine organisms according to Fourier transformation of the pulse compression signals, and identifying biological species of the target to be detected by utilizing the difference of scattering of the anatomical structures of the marine organisms to different acoustic frequencies and utilizing the existing identification method.
Compared with the prior art, the invention has the beneficial effects that:
1. the method is based on the combination of broadband and split beam signals, can be used as split beams and broadband single beams independently through the multiplexing of a four-quadrant split beam transducer, can also be used through the combination of signal alternate transmission/reception, and realizes the measurement and tracking of the single object intensity of living things such as fish, the evaluation and distribution of resource quantity and the identification of biological species by utilizing the working mode of the split beam transducer of a multi-mode phase control device comprising a planar transducer array;
2. the invention is based on the combination treatment of broadband signals and split beams, and can simultaneously solve the problems of fish target tracking and biological species identification;
3. the invention is based on the combination processing of broadband and split beams, so that signal estimation is more stable, the target detection capability is improved, and the accuracy of fishery resource estimation is improved;
4. the invention is based on broadband signal processing, effectively utilizes broadband spectrum scattering characteristics of the target to be detected, and can improve the biological group detection spatial resolution and the biological species identification accuracy;
5. the invention is based on the combination treatment of broadband and split beams, can be applied to the long-term monitoring and resource quantity evaluation of fishery resources in water areas such as ocean, river and the like, and can be used for monitoring the time-space distribution of the fishery resources.
Drawings
FIG. 1 is a flow chart of a split beam based method of identifying an underwater target of the present invention;
FIG. 2 is a schematic illustration of a "narrowband-wideband" beam emitted by a four-quadrant split-beam transducer alternately and periodically in a split-beam based method of identifying an underwater target of the present invention;
fig. 3 is a schematic structural diagram of a four-quadrant split beam transducer in a split beam based method for identifying an underwater target according to the present invention.
Detailed Description
The invention will now be further described with reference to the accompanying drawings.
As shown in fig. 1, the invention provides a split beam-based underwater target identification method, which uses a broadband four-quadrant split beam transducer as a front-end information sensor; the method specifically comprises the following steps:
the four-quadrant split beam transducer transmits sound wave signals with specific frequency and specific bandwidth to a sea area in a mode of 'narrow-band-broadband' beam alternating period, transmits the sound wave signals to a marine organism target to be detected in the sea area, generates scattered echo signals, and sequentially reflects the scattered echo signals to four channel receivers of the four-quadrant split beam transducer;
each channel receiver sequentially receives echo signals reflected from a target to be detected, performs gain control amplification and AD analog-to-digital conversion on each echo signal to obtain digital signals alternately transmitted by the narrow bands and the wide bands of the four channels, and sends the digital signals alternately transmitted by the narrow bands and the wide bands of the four channels to a signal mixer;
the signal mixer performs beam splitting processing of narrowband signals on the received digital signals alternately transmitted by the narrowband and the broadband of the four channels to obtain the position of a target to be detected in split beams;
specifically, as shown in fig. 1 and 2, the signal mixer extracts narrowband signals in the digital signals of four channels respectively to form four half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a first quadrant area where the first channel receiver is located and a second quadrant area where the second channel receiver is located respectively, and combines the narrow-band signals into upper half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a second quadrant area where the second channel receiver is located and a third quadrant area where the third channel receiver is located respectively, and the narrow-band signals are combined into left half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a third quadrant area where the third channel receiver is located and a fourth quadrant area where the fourth channel receiver is located respectively, and the narrow-band signals are combined into a lower half beam of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a fourth quadrant area where the fourth channel receiver is located and a first quadrant area where the first channel receiver is located respectively, and the narrow-band signals are combined into a right half beam of the split beam array;
determining a vertical deviation angle of a target to be measured through the phase difference between the upper half beam of the split beam array and the lower half beam of the split beam array, and determining a horizontal deviation angle of the target to be measured through the phase difference between the left half beam of the split beam array and the right half beam of the split beam array; and determining the position of the object to be measured in the split beam according to the vertical offset angle and the horizontal offset angle of the object to be measured.
Specifically, the signals received by the four quadrant array elements of the first quadrant area, the second quadrant area, the third quadrant area and the fourth quadrant area are sequentially X 1 ，X 2 ，X 3 ，X 4
By finding X 1 And X 4 Or X 2 And X 3 Is used to detect the correlation peak R (τ) 0 ) Thus, the phase difference of the array element receiving signals passing through the upper half beam of the split beam array and the lower half beam of the split beam array is obtained, and the phase difference is used as the azimuth angle of the target to be detected, namely the vertical offset angle phi;
by finding X 1 And X 2 Or X 3 And X 4 Is a cross-correlation function R of 1 (τ) detection of correlation peak R 1 (τ 01 ) Thus, the phase difference of the left half wave beam of the split wave beam array and the right half wave beam of the split wave beam array, which are used as the azimuth angle of the target to be measured, namely the horizontal offset angle theta, of the array element receiving signals are obtained;
determining the distance r of an object to be measured:
wherein c is the speed of sound; t is the time of detecting the echo of the target to be detected;
establishing a spherical coordinate system with the center of the split beam array as the origin of coordinates, and taking the position of the object to be measured in the split beam array as the coordinates
And the coordinates are set
Performing coordinate conversion to obtain the position of the object to be measured in a rectangular coordinate system as coordinates (x, y, z);
wherein,,
and taking the position of the object to be measured in the rectangular coordinate system as the position of the object to be measured in the split beam array.
Adopting a Kalman filter as a target tracker to realize tracking of a target to be detected; other types of trackers, such as multi-hypothesis tracker (multi-hypothesis tracker MHT), alpha-beta tracker, and more complex algorithms may be employed to achieve tracking of the target under test.
Meanwhile, the signal synthesizer carries out synthesis processing of broadband signals on the received digital signals of the four channels, extracts broadband signals in the digital signals of the four channels, synthesizes the four broadband signals to obtain a single-beam broadband signal, and processes the single-beam broadband signal to obtain the size and biological species of a target to be detected;
specifically, the signal synthesizer extracts broadband signals in the received digital signals of the four channels, and synthesizes the four broadband signals to obtain synthesized broadband signals;
performing time-varying gain compensation on the synthesized broadband signal to compensate the expansion loss and absorption loss of the sound wave propagating in the water, obtaining the real echo energy of the target, and compensating according to the distance to obtain the broadband signal after gain compensation:
x RX ＝x TX +Loss
wherein x is TX Is a synthesized width signal of the transmitted time sequence; x is x RX Receiving a time-series gain-compensated wideband signal;
wherein,,
Loss＝20log R+αR (1)
where Loss is the Loss compensation amount in units of: dB (dB); r is the distance of the object to be measured, unit: rice; alpha is the absorption coefficient of water, unit: dB/m;
and (3) adopting a matched filter and adopting a Fourier transform and inverse Fourier transform method to perform pulse compression processing on the broadband signal after gain compensation to obtain a compressed pulse signal:
x MF ＝F -1 {F(x TX )F(x RX )} (2)
wherein x is MF Is a pulse compressed signal; f (·) is the Fourier transform; f (F) -1 {. The inverse fourier transform;
pulse compression signal x MF The spatial resolution of the pulse compression signal is dependent on the bandwidth of the signal, a signal detection threshold is set according to the marine organism detection condition, peak separation processing is carried out on the pulse compression signal, the initial position and the target echo width of the target to be detected are obtained, the scattering sectional area of each target is measured, and the size of the target to be detected is estimated by utilizing the functional relation between the target strength and the single length of the target to be detected; based on waitingMeasuring the size of a target, estimating the density and density distribution of the biological group in the monitoring area, and further estimating the biomass of the biological group; the method comprises the steps of obtaining a biological group density based on echo signals by utilizing an echo integration method.
And obtaining broadband spectrums of echoes of different anatomical structures of the marine organisms according to Fourier transformation of the pulse compression signals, and identifying biological species of the target to be detected by utilizing the difference of scattering of the anatomical structures of the marine organisms to different acoustic frequencies and utilizing the existing identification method.
And fusing the positions, the sizes and the types of the targets to be detected in the four split beams to obtain information of the targets to be detected, and finishing accurate identification of the targets to be detected.
Wherein, as shown in fig. 2 and 3, the four-quadrant split beam transducer comprises:
the circular plane array and a plurality of tap, circular plane array divide into 4 quadrant areas that are connected end to end, and it includes from right to left: a first quadrant region with an upper right of the first channel receiver, a second quadrant region with an upper left of the second channel receiver, a third quadrant region with a lower left of the third channel receiver, and a fourth quadrant region with a lower right of the fourth channel receiver; and the first quadrant area, the second quadrant area, the third quadrant area and the fourth quadrant area are respectively provided with a tap.
The first quadrant region, the second quadrant region, the third quadrant region and the fourth quadrant region comprise a plurality of primitives, and the number of the primitives in the first quadrant region, the second quadrant region, the third quadrant region and the fourth quadrant region is equal; n, N being determined by the beam width, conversion efficiency and side lobe level.
Aiming at the technical problem that the existing identification method cannot realize long-term and real-time fixed monitoring of fishery resources such as oceans and the like, the invention provides a method for identifying underwater species targets and evaluating the fishery resource amount in water areas such as oceans, inland rivers, large-scale aquaculture net cages and the like. The method utilizes a multi-mode phase control device comprising a planar transducer array, splits the working mode of a beam transducer, adopts a combination method of broadband single beams and split beams, and simultaneously realizes target tracking of biological monomers such as fishes, identification of species, target strength measurement and fishery resource quantity evaluation of water areas such as oceans, inland rivers, large-scale aquaculture net cages and the like; the method can also be applied to a monitoring network formed by a plurality of nodes so as to realize the networking and long-term monitoring and evaluation of the specific water area.
The invention relates to an integrated method for acoustic evaluation and identification of fishery resources based on split beams, in particular to an integrated method for realizing accurate evaluation and species identification of fishery resources by using a broadband-narrowband combination method of split beams. The broadband single beam and the split beam are combined and optimized by utilizing an integrated combination design strategy, and the broadband signal and the narrow-band signal are combined in turn for transmitting and receiving or are independently transmitted and received, and the received echo broadband signal of the four quadrants of the split beam is synthesized, so that the broadband signal can be obtained, and the split beam signal can be obtained by independent processing, thereby realizing the monitoring of fishery resources in a monitored water area, the positioning and tracking of a single target, the measurement of the target strength and the evaluation of the resource quantity.
Finally, it should be noted that the above embodiments are only for illustrating the technical solution of the present invention and are not limiting. Although the present invention has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the present invention, which is intended to be covered by the appended claims.
Claims (5)
1. A method of identifying an underwater target based on split beams, the method comprising:
the four-quadrant split beam transducer transmits sound wave signals with specific frequency and specific bandwidth to a sea area in a mode of 'narrow-band-broadband' beam alternating period, transmits the sound wave signals to a marine organism target to be detected in the sea area, generates scattered echo signals, and sequentially reflects the scattered echo signals to four channel receivers of the four-quadrant split beam transducer;
each channel receiver sequentially receives echo signals reflected from a target to be detected, performs gain control amplification and AD analog-to-digital conversion on each echo signal to obtain digital signals alternately transmitted by the narrow bands and the wide bands of the four channels, and sends the digital signals alternately transmitted by the narrow bands and the wide bands of the four channels to a signal mixer;
the signal mixer performs beam splitting processing of narrowband signals on the received digital signals alternately transmitted by the narrowband and the broadband of the four channels to obtain the position of a target to be detected in split beams;
meanwhile, the signal synthesizer carries out synthesis processing of broadband signals on the received digital signals of the four channels, extracts broadband signals in the digital signals of the four channels, synthesizes the four broadband signals to obtain a single-beam broadband signal, and processes the single-beam broadband signal to obtain the size and biological species of a target to be detected;
fusing the positions, the sizes and the biological species of the targets to be detected in the four split beams to obtain information of the targets to be detected, and completing identification of the targets to be detected;
the signal synthesizer is used for synthesizing the broadband signals of the four channels, extracting the broadband signals in the digital signals of the four channels, synthesizing the four broadband signals to obtain a single-beam broadband signal, and processing the single-beam broadband signal to obtain the size and biological species of the target to be detected; the specific process is as follows:
the signal synthesizer extracts broadband signals in the received digital signals of the four channels, and synthesizes the four broadband signals to obtain synthesized broadband signals;
performing time-varying gain compensation on the synthesized broadband signal to compensate the expansion loss and absorption loss of the sound wave propagating in the water, obtaining the real echo energy of the target, and compensating according to the distance to obtain the broadband signal after gain compensation:
x RX ＝x TX +Loss
wherein x is TX Is a synthesized width signal of the transmitted time sequence; x is x RX Receiving a time-series gain-compensated wideband signal;
wherein,,
Loss＝20logR+αR (1)
where Loss is the Loss compensation amount in units of: dB (dB); r is the distance of the object to be measured, unit: rice; alpha is the absorption coefficient of water, unit: dB/m;
and (3) adopting a matched filter and adopting a Fourier transform and inverse Fourier transform method to perform pulse compression processing on the broadband signal after gain compensation to obtain a compressed pulse signal:
x MF ＝F -1 {F(x TX )F(x RX )} (2)
wherein x is MF Is a pulse compressed signal; f (·) is the Fourier transform; f (F) -1 {. The inverse fourier transform;
pulse compression signal x MF The spatial resolution of the pulse compression signal is dependent on the bandwidth of the signal, a signal detection threshold is set according to the marine organism detection condition, peak separation processing is carried out on the pulse compression signal, the initial position of the target to be detected and the target echo width are obtained, and then the size of the target to be detected is estimated;
and obtaining broadband spectrums of echoes of different anatomical structures of the marine organisms according to Fourier transformation of the pulse compression signals, and identifying biological species of the target to be detected by utilizing the difference of scattering of the anatomical structures of the marine organisms to different acoustic frequencies and utilizing the existing identification method.
2. The split-beam based underwater target identification method of claim 1 wherein the four-quadrant split-beam transducer comprises:
the circular plane array and a plurality of tap, circular plane array divide into 4 quadrant areas that head and tail are connected, include: a first quadrant region with an upper right of the first channel receiver, a second quadrant region with an upper left of the second channel receiver, a third quadrant region with a lower left of the third channel receiver, and a fourth quadrant region with a lower right of the fourth channel receiver.
3. The method of claim 2, wherein the first, second, third and fourth quadrants are each provided with P primitives, P being determined by a beam width, a conversion efficiency and a side lobe level.
4. The method for identifying an underwater target based on split beams according to claim 3, wherein the signal mixer performs beam splitting processing of narrowband signals on the received digital signals alternately transmitted by narrowband and wideband of four channels to obtain the position of the target to be detected in the split beams; the specific process is as follows:
the signal mixer extracts narrow-band signals in the digital signals of the four channels respectively to form four half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a first quadrant area where the first channel receiver is located and a second quadrant area where the second channel receiver is located respectively, and combines the narrow-band signals into upper half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a second quadrant area where the second channel receiver is located and a third quadrant area where the third channel receiver is located respectively, and the narrow-band signals are combined into left half beams of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a third quadrant area where the third channel receiver is located and a fourth quadrant area where the fourth channel receiver is located respectively, and the narrow-band signals are combined into a lower half beam of the split beam array;
the signal mixer extracts narrow-band signals in digital signals of a fourth quadrant area where the fourth channel receiver is located and a first quadrant area where the first channel receiver is located respectively, and the narrow-band signals are combined into a right half beam of the split beam array;
determining a vertical deviation angle of a target to be measured through the phase difference between the upper half beam of the split beam array and the lower half beam of the split beam array, and determining a horizontal deviation angle of the target to be measured through the phase difference between the left half beam of the split beam array and the right half beam of the split beam array; and determining the position of the object to be measured in the split beam according to the vertical offset angle and the horizontal offset angle of the object to be measured.
5. The method for identifying an underwater target based on split beams according to claim 4, wherein the vertical offset angle of the target to be measured is determined by the phase difference between the upper half beam of the split beam array and the lower half beam of the split beam array, and the horizontal offset angle of the target to be measured is determined by the phase difference between the left half beam of the split beam array and the right half beam of the split beam array; determining the position of the target to be measured in the split beam according to the vertical offset angle and the horizontal offset angle of the target to be measured; the specific process is as follows:
the signals received by the four quadrant array elements of the first quadrant area, the second quadrant area, the third quadrant area and the fourth quadrant area are sequentially X 1 ，X 2 ，X 3 ，X 4
By finding X 1 And X 4 Or X 2 And X 3 Is used to detect the correlation peak R (τ) 0 ) Thereby obtaining the phase difference of the array element receiving signals passing through the upper half beam of the split beam array and the lower half beam of the split beam array, and taking the phase difference as the azimuth angle, namely the vertical offset angle, of the target to be measured
By finding X 1 And X 2 Or X 3 And X 4 Is a cross-correlation function R of 1 (τ) detection of correlation peak R 1 (τ 01 ) Thus, the phase difference of the left half wave beam of the split wave beam array and the right half wave beam of the split wave beam array, which are used as the azimuth angle of the target to be measured, namely the horizontal offset angle theta, of the array element receiving signals are obtained;
determining the distance r of an object to be measured:
wherein c is the speed of sound; t is the time of detecting the echo of the target to be detected;
establishing a spherical coordinate system with the center of the split beam array as the origin of coordinates, and taking the position of the object to be measured in the split beam array as the coordinates
And the coordinates are set
Performing coordinate conversion to obtain the position of the object to be measured in a rectangular coordinate system as coordinates (x, y, z);
and taking the position of the object to be measured in the rectangular coordinate system as the position of the object to be measured in the split beam array.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108710133A (en) * | 2018-05-07 | 2018-10-26 | 哈尔滨工程大学 | A kind of planar phased array transducer array and phased method |
| CN109782291A (en) * | 2018-12-25 | 2019-05-21 | 中国科学院声学研究所 | A kind of planar array transducer array and multi-modal phase-control device |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107589419A (en) * | 2017-07-25 | 2018-01-16 | 武汉滨湖电子有限责任公司 | A kind of method of energy peak joint wideband Range Profile Objective extraction |
| CN108710133A (en) * | 2018-05-07 | 2018-10-26 | 哈尔滨工程大学 | A kind of planar phased array transducer array and phased method |
| CN109782291A (en) * | 2018-12-25 | 2019-05-21 | 中国科学院声学研究所 | A kind of planar array transducer array and multi-modal phase-control device |
Non-Patent Citations (2)
| Title |
|---|
| 典型分裂波束声学探测系统及其应用;张同伟 等;《舰船科学技术》;20190228;第41卷(第2期);全文 * |
| 宽带分裂波束探鱼仪关键技术研究及试验验证;吴陈波;《中国优秀硕士学位论文全文数据库 农业科技辑》;20210315(第03期);第7-18页 * |
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