水下无人系统学报

Ocean Acoustic Target Detection Technologies: a Review

YANG Yi-xin, HAN Yi-na, ZHAO Rui-qin, LIU Xiong-hou, WANG Yong

2018, 26(5): 369-386. doi: 10.11993/j.issn.2096-3920.2018.05.001

[Abstract](2474) [PDF 3847KB](4754)

Abstract:

Underwater Multi-Target Tracking Based on Collaborative Detection Data Fusion

Long-xiang, YU Han-jun, SHENG Xue-li, HAN Xiao, HAO Hao-yan, CHEN Yang

2018, 26(5): 387-394. doi: 10.11993/j.issn.2096-3920.2018.05.002

[Abstract](1133) [PDF 1197KB](734)

Abstract:
在高杂波密度的水下环境中, 若只利用局部传感器来跟踪多个目标, 会产生较高的虚警, 而且跟踪效果受限于传感器本身性能。为此文中基于分布式数据融合模型, 首先在各个无人平台上利用联合概率数据关联(JPDA)形成局部航迹, 然后再用匈牙利算法实现对关联矩阵的最优分配从而达到航迹的实时关联, 最后通过凸组合融合算法形成全局航迹。仿真结果表明, 经过此方法完成的多目标跟踪结果具有更好的可靠性, 其跟踪精度基本在两站跟踪精度之间且具有较低的跟踪误差, 适合在未知基站估计精度的系统中获得更为可信的估计结果。

Underwater Acoustic Communication Technology Adopting Low Complexity Single Carrier Frequency-Domain Turbo Equalization

XI Rui, DANG Qian-qian, HE Cheng-bing, ZHANG Rui-yu, ZHANG Qun-fei

2018, 26(5): 395-402. doi: 10.11993/j.issn.2096-3920.2018.05.003

[Abstract](858) [PDF 1376KB](561)

Abstract:
Underwater acoustic communication in shallow sea has the characteristics of severe multipath delay spread, channel fading and low signal-to-noise ratio(SNR). To overcome the high computation complexity and high sensitivity to receiver parameters of conventional time-domain decision feedback equalizer, a low complexity frequency-domain Turbo iterative equalization method is proposed for sparse underwater communication channel, which is based on single-carrier block transmission structure with spreading codes. At the transmitter spreading codes are inserted between data blocks as the cyclic prefixes. At the receiver known spreading codes are employed to estimate the sparse channel and the rotational phase caused by Doppler shift, then the frequency-domain Turbo equalization technique based on the minimum mean square error criteria and the multichannel joint processing method are used to eliminate the intersymbol interference(ISI) caused by the multipath effect. The performance of the system is improved significantly. Lake test shows that the underwater communication with effective data rates of 3 kbps and 4.5 kbps is achieved via QPSK and 8PSK modulation, respectively, at a communication distance of 10.8 km, and error-free transmission is always achieved in three times of iterative equalization. This study may provide a reference for the research of robust underwater acoustic communication with high data rate.

Novel Surrogate Modeling Method in Uncertainty Propagation from Environment to Acoustic Field

LIU Zong-wei, LÜ Lian-gang, YANG Chun-mei, JIANG Ying, YU Xiao-lin, HUANG Long-fei

2018, 26(5): 403-408. doi: 10.11993/j.issn.2096-3920.2018.05.004

[Abstract](723) [PDF 669KB](336)

Abstract:
Uncertainty of ocean environmental parameters is one of the main sources of uncertainty in underwater acoustic field prediction. In addition, the relationship between the environmental parameters and the acoustic field may be highly nonlinear, so it is difficult to calculate the uncertainty of acoustic field through the uncertainty of ocean environmental parameters. The traditional Monte Carlo method needs to run the acoustic field calculation model many times, which results in too much calculation. To overcome the drawbacks of the existing methods, this paper proposes a new surrogate modeling method based on polynomial-chaos-Kriging(PC-Kriging) which can calculate the uncertainty transfer process efficiently from ocean environmental parameters to acoustic field. This method extracts the global trend of the system response using the polynomial chaos expansions(PCE) and approaches the local response using the Kriging method. Computer simulations using the general mismatched benchmark acoustic environmental model is performed to verify the proposed method in two aspects — the accuracy of the model approaching accuracy and the probability density function of the propagation loss. The results indicate that the surrogate modeling method based on the PC-Kriging is efficient and better in accuracy than the PCE or Kriging method. The probability density functions of propagation loss obtained by PC-Kriging and direct Monte Carlo are consistent, showing the suitability of PC-Kriging for the uncertainty propagation from environment to acoustic field.

Target Movement Parameter Estimation Based on Particle Swarm Optimization Algorithm

GUAN Shan-zheng, CHEN Shao-hua, CHEN Chuan

2018, 26(5): 409-414. doi: 10.11993/j.issn.2096-3920.2018.05.005

[Abstract](841) [PDF 627KB](360)

Abstract:
Considering the demand for real-time property and accuracy of an underwater target passive tracking and location system, a target parameter estimation method is proposed by using the target’s azimuth and Doppler shift information. With the measured target’s azimuth variation and Doppler frequency shift, a parameter estimation equation is established based on the minimum mean square error(MMSE) criterion, and a set of motion parameters is determined by the particle swarm optimization(PSO) algorithm to minimize the mean square error function, thus the accurate estimations of target’s real-time position, velocity, and closest passing distance are achieved. Simulation results show that the PSO algorithm converges more rapidly with equivalent convergence precision compared with the extended Kalman filter algorithm; and for the close-distance and high-speed target, the PSO algorithm can provide accurate prediction of target’s closest passing distance and high tracking precision before and after it passes by, respectively. This research is expected to provide a reference for passive tracking of underwater target and accurate estimation of movement parameters.

Array Layout Design and Beampattern Optimization for Circular-Array MIMO Sonar with Limited Physical Size

WU Jing-rong, LIU Xiong-hou, FAN Kuan, SUN Chao, YANG Yi-xin

2018, 26(5): 415-420. doi: 10.11993/j.issn.2096-3920.2018.05.006

[Abstract](741) [PDF 915KB](460)

Abstract:
By using a receiving circular array, the traditional active sonar can achieve a 360° view field. However, it suffers from a wide beamwidth and a high sidelobe level under the condition of limited physical size of the circular array. To address this problem, we focus on a circular-array multiple-input multiple-output(MIMO) sonar, and propose the corresponding array layout design and beampattern optimization method. The circular-array MIMO sonar is composed of a circular transmitting array and a circular receiving array. And for the purpose of suppressing the sidelobe level, the radius of the two arrays and the relative rotation angle between them are optimized synchronously. Furthermore, to obtain a low sidelobe beampattern, we calculate the weights on the virtual planar array of the designed circular-array MIMO sonar by solving a convex optimization problem. Specifically, the objective function is established to minimize the sidelobe level and set the mainlobe direction response without distortion, and the Euclid norm constraint on the calculated weights is used to ensure relatively robust beampattern performance. Numerical simulations show that the proposed method can obtain a lower sidelobe level than the traditional active sonar with same physical array size and same mainlobe width.

Superdirective Beamforming Method for Cylindrical Arrays Based on Eigenbeam Decomposition and Synthesis

ZHU Shao-hao, YANG Yi-xin, WANG Yong

2018, 26(5): 421-426. doi: 10.11993/j.issn.2096-3920.2018.05.007

[Abstract](1000) [PDF 775KB](413)

Abstract:
To apply the small-aperture sensor array with relatively high spatial directivity to the space-limited unmanned undersea systems or other platforms, the superdirective beamforming method is used to improve the spatial directivity and array gains of the sensor array, and the target detection performance of the array is improved. First, a superdirective beamforming method based on eigenbeam decomposition and synthesis(EBDS) for circular arrays is introduced; then, a superdirective beamforming model for cylindrical arrays is proposed by using two-level subarrays at arbitrary pitch direction, and the noise cross-spectral matrix with circulant property in the isotropic noise field is derived. Simulation results of beampatterns and array gains show that the proposed superdirective beamforming method has many advantages over the conventional beamforming method in the directivity and the array gain at low frequency, which extends the application scope of cylindrical arrays with the EBDS and enhances the detection ability of cylindrical arrays. This study may provide a reference for application of small-aperture sensor array to detection of unmanned undersea systems at low frequency.

Capability Requirements Analysis of Underwater Acoustic Communication for Torpedo Cooperative Guidance

YUE Ling, FAN Shu-hong, FENG Xi-an

2018, 26(5): 427-433. doi: 10.11993/j.issn.2096-3920.2018.05.008

[Abstract](930) [PDF 658KB](480)

Abstract:
Underwater acoustic communication plays an important role in torpedo informatization and networked cooperative operations. A new concept of underwater weapon attack mode, including multi-torpedo salvo, cooperative guidance and cluster attack, is proposed based on the submarine launched heavy wire-guided torpedo antisubmarine warfare(ASW). Linear centralized type and triangular distributed type of multi-torpedo cooperative guidance systems are constructed. Then, the capability requirements of underwater acoustic communication such as operation range, data rate, bit error rate and Doppler adaptability are analyzed quantitatively for the proposed multi-torpedo cooperative guidance systems. Comparison with the performance parameters of the foreig6n commercial underwater acoustic modem proves that the existing underwater acoustic communication technology can effectively support multi-torpedo characteristic level cooperative guidance and cluster attack. This research may provide a reference for engineering realization of torpedo weapon cluster operation, network detection and cooperative guidance.

Simulation Analysis of Joint Localization Algorithm Based on Distributed Arrays

WANG Zhi-gang, CHEN Shao-hua, WANG Wei

2018, 26(5): 433-438. doi: 10.11993/j.issn.2096-3920.2018.05.009

[Abstract](659) [PDF 538KB](361)

Abstract:
A multi-array joint localization system has the performances of strong anti-interference and survivability, compared with the bearing-only target localization and tracking algorithm, which needs a large amount of calculation and is of poor real-time performance and low accuracy of localization and estimation. In this paper, a distributed arrays based on joint localization algorithm is proposed for underwater acoustic network. Simulation models of the localization methods of Jacobi iteration, triangular center of gravity, least square method(LSM) are presented. The simulation performances of three localization methods for different array numbers and distribution situations are analyzed and compared. Simulation results show that the Jacobi iteration method with tri-array can achieve better positioning accuracy and convergence performance than the other two methods. Furthermore, the suitable parameters of array layout, array numbers, and distances among arrays for distributed arrays joint localization are proposed to improve the target localizing performance and the network survivability. This study may provides a reference for engineering application of multi-array target positioning.

Non-Threatening Degree Assessment Method of Sonar Targets Based on Multi-Source Information Fusion

ZHOU Bin, WANG Qing, QUAN Heng-heng

2018, 26(5): 439-443. doi: 10.11993/j.issn.2096-3920.2018.05.010

[Abstract](697) [PDF 2505KB](641)

Abstract:
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[6] 吕琳. 未来反潜战中的多基地声呐作战[J]. 电子世界, 2018(4): 109-111.
[7] 王杰贵, 罗景青. 基于多目标多特征信息融合数据关联的无源跟踪方法[J]. 电子学报, 2004, 32(6): 1013-1016.
Wang Jie-gui, Luo Jing-qing. Passive Tracking Based on Data Association with Information Fusion of Multi-Fea- ture and Multi-Target[J]. Acta Electronica Sinica, 2004, 32(6): 1013-1016.
[8] 孙启臣, 郭伟震, 闫倩倩, 等. 一种基于灰关联分析的多目标跟踪算法[J], 鲁东大学学报, 2017, 33(1): 20- 25.
Sun Qi-chen, Guo Wei-zhen, Yan Qian-qian, et al. A Multi-target Tracking Algorithm Based on Grey Relational Analysis[J]. Ludong University Journal(Natural Science Edition), 2017, 33(1): 20-25.
[9] 孙伟, 尚金涛, 朱鲲. 一种新的多目标融合关联算法[J]. 声学与电子工程, 2016(3): 1-3.
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An Improved Hungarian Algorithm for Multiple Hypothesis Tracking

ZHAO Wei-kang, HAN Yi-na, ZHANG Hao-yu, YANG Yi-xin, LIU Qing-yu

2018, 26(5): 444-448. doi: 10.11993/j.issn.2096-3920.2018.05.011

[Abstract](753) [PDF 457KB](913)

Abstract:
Hungarian algorithm is a core algorithm in multiple hypothesis tracking technology, and it takes up most of the computation time in multiple hypothesis tracking(MHT). Considering that the assignment problem in the MHT has particularity, i.e., the efficiency matrix is sparse, this paper proposes a method for reducing the dimension of the efficiency matrix, and the computation flow is given. Comparison of the time consumption between the proposed method and traditional Hungarian algorithm in dealing with larger efficiency matrix shows that the proposed method greatly reduces the amount of computation while ensuring consistency with the results of the Hungarian algorithm.

Design and Application of Acoustic Communication System for Unmanned Undersea Vehicle

MA Lu, WEN Meng-hua, QIAO Gang, SUN Zong-xin, CHI Qing-xi, LI Shan, LI Zhi-qiang

2018, 26(5): 449-455. doi: 10.11993/j.issn.2096-3920.2018.05.012

[Abstract](1080) [PDF 1167KB](702)

Abstract:
To remotely control and monitor an unmanned undersea vehicle(UUV), it is necessary to establish a communication link between the UUV and the surface control platform. In this study, a telecommunication system adopting acoustic wave as the carrier is designed for the UUV. Because the underwater acoustic channel has the significant characteristics of multipath interference and Doppler shift, this system uses incoherent multi-carrier frequency shift keying (MFSK) technology to ensure the stability of acoustic communication link. In order to further strengthen the transmission reliability of telecontrol instruction and status information, the stop-and-wait automatic repeat request(ARQ) protocol is used for error control. All of the control algorithms are timely realized on the low-power digital signal processor(DSP) hardware platform. Tests in South China Sea verify the practicability and stability of the present system.

Key Technologies of Multistatic Sonar Fusion Detection

ZHANG Hao-yu, HAN Yi-na, ZHAO Wei-kang, YANG Yi-xin, LIU Qing-yu

2018, 26(5): 456-464. doi: 10.11993/j.issn.2096-3920.2018.05.013

[Abstract](782) [PDF 914KB](680)

Abstract:
To solve the fusion detection problem for multistatic sonar, this paper discusses three key technologies, i.e., measurement model, data association, and tracker performance model. The measurement model includes the error distributions of time, azimuth, position and sound velocity, as well as the localization expression of a target. The expression of each error factor and the expression of localization error are given. Data association is an important part of fusion detection to solve the assignment problem between measurements and known targets. The methods of nearest neighbor data association and multiple hypothesis data association are introduced in detail. The two data association methods use the same data model, measurement model and motion model. Simulations on the nearest neighbor data association and multiple hypothesis data association show that the target can be well tracked. The tracker performance model is used to evaluate the output quality of the tracker. The output quality is evaluated according to three performance parameters, i.e., tracking probability of detection, tracking fragmentation, and false alarm rate if tracking. According to the performance parameters from simulation, the output quality of the multiple hypothesis data association tracker is significantly better than that of the nearest neighbor data association tracker.

Mobile Underwater Acoustic Communication System Based on AD Variable Sampling

WANG Xiao-yang, ZHENG Si-yuan, LI Bin, TONG Feng

2018, 26(5): 465-469. doi: 10.11993/j.issn.2096-3920.2018.05.014

[Abstract](548) [PDF 1004KB](380)

Abstract:
For the Doppler problem in mobile underwater acoustic communication of underwater mobile platforms such as autonomous undersea vehicle(AUV), the traditional software variable sampling Doppler correction method needs to accept one complete frame signal at first, and the signal is resampled after Doppler estimation, so it has high computational complexity and is difficult to implement in hardware. In this paper, an AUV mobile communication scheme based on analog-to-digital(AD) variable sampling suppression Doppler is proposed. The Doppler estimation is performed in the front part of the signal, then the AD sampling rate is adjusted by the microcontroller unit(MCU) to receive the signal, which is equivalent to Doppler compensation directly to the signal. The underwater acoustic communication system designed according to the scheme can communicate in real time and improve the communication quality. Simultaneously, adopting the direct spread spectrum technology and channel coding helps further improve communication performance of the system. Sea trial verifies the effectiveness of the proposed scheme.

Analysis on the Key Technology of Integrated Underwater Detection and Communication

LU Jun, ZHANG Qun-fei, SHI Wen-tao

2018, 26(5): 470-479. doi: 10.11993/j.issn.2096-3920.2018.05.015

[Abstract](1611) [PDF 5000KB](853)

Abstract:
The integrated technology combined with underwater acoustic communication and underwater detection possesses the advantages of reducing platform volume and power consumption, and enhancing concealment. However, the development of this technology is restricted by the physical characteristics, acoustic characteristics and underwater acoustic environment of a sonar. In this paper, an integrated detection and communication technology based on communication signals under the sharing system is researched by means of the existing radar communication integration technology, underwater acoustic communication and detection technology. The detection and communication performances of the commonly used underwater acoustic communication modulation mode are analyzed, and the modulation modes suitable for underwater shared waveforms are selected. Aiming at the single base operation mode, a multi-level self-interference cancellation method and a method for estimating and detecting target based on the characteristics of communication signal are proposed, and a emiting leakage analog canceller is designed. Aiming at the bistatic operation mode, a spatial matrix filter is used to eliminate the direct waves, the relationship among signal-to-noise ratio(SNR), bit error rate(BER) and detection performance are analyzed, and the transmitted signal and echo wave which are obtained by direct wave are matched for filtering, so the performance of target parameter estimation and detection is improved.

Effect of Underwater Acoustic Signal Frequency on Performance of Time Reversal Detection

WANG Ming-hao, WANG Hai-yan, SHEN Xiao-hong, ZHANG Zhi-chen

2018, 26(5): 480-486. doi: 10.11993/j.issn.2096-3920.2018.05.016

[Abstract](870) [PDF 1089KB](601)

Abstract:
How to detect weak targets in complex multi-path shallow sea environment has become a research hotspot in the field of underwater sound detection, in which the time reversal(TR) has broad applications. According to literature, the combination of passive time-reversal(PTR) and array signal processing(ASP) can improve the performance of the weak target detection and positioning. In complex multi-path shallow sea environment, the main peak and the side peak of TR focusing overlap when the signal pulse width is greater than the threshold. Therefore, the overlapping could have a great impact on the power of focusing peak. According to these phenomena, this paper derives the relationship between the processing gain of PTR signal-to-noise ratio and the signal frequency, and reaches a conclusion that since TR processing cannot completely avoid delay spread (overlapping of sound line beyond mirror reflection), as for the same PTR detection system, its performance of detection and positioning relates to both the matching of estimated signal channel and the features(frequency and pulse width) of sound source in time domain. This study may provide a reference for TR communication and TR detection, especially for the case where information source or sound source is the signal with large pulse-width and narrow band.

Design and Implementation of a New Type of Acoustic Modem Analog Circuit

LIAO Jian-yu, SHEN Xiao-hong, LÜ Xiao-peng, WANG Hai-yan

2018, 26(5): 487-491. doi: 10.11993/j.issn.2096-3920.2018.05.017

[Abstract](877) [PDF 1049KB](497)

Abstract:
In view of the large volume, high power consumption and short communication distance of the traditional underwater acoustic modem, this study analyzed the key issues of relating the transmitting channel and the receiving channel in the overall design of the underwater acoustic modem. These issues include class-D power amplifier circuit design, dual resonant circuit impedance matching circuit design and receiving preprocessing circuit design. Subsequently, a class-D power amplifier circuit with small volume and high conversion efficiency, as well as a new combined bandpass filter design method and pro-gram-controlled automatic gain control(AGC) implementation method, was proposed. These methods were applied to the test prototype, and the prototype passed the pool test and the Danjiangkou reservoir communication test. The test results show that the sound source level of the prototype is improved by 10 dB, and its communication distance reaches to 4.8 km compared with the traditional prototype, which verifies the feasibility of the proposed scheme. This design may provide a reference for the development of underwater acoustic modem prototype.

A Method for Background Suppression of Sonar Image Using Gaussian Mixture Model and Radon Transform

FAN Wei, ZHU Dai-zhu, ZHANG De-ze, ZENG Sai

2018, 26(5): 492-497. doi: 10.11993/j.issn.2096-3920.2018.05.018

[Abstract](783) [PDF 3274KB](487)

Abstract:
The background of sonar image of small underwater moving target fluctuates with space and time. The background suppression is one of the key processes in sonar detection. In this paper, the Gaussian mixture model is used to model the amplitude variation of each azimuth-range resolution cell of sequential sonar image, so as to suppress the main background of highlight area and highlight band in the sonar image. In order to solve the problem of residual noise from the Gaussian mixture model, the continuous change characteristics of the track from an underwater moving target are considered, the line features of the history-accumulated sonar image are extracted, and the residual noise is filtered out by Radon transform and inverse Radon transform. The analysis of multi-beam sonar data from measurement under the conditions of small underwater target’s linear motion and cross-azimuth curvilinear motion shows that the complex sonar background can be removed and the clean sonar back-ground can be obtained by using the Gaussian mixture model and the filtering method via Radon transform, which can be used in sonar detection of underwater moving targets.

Application of Broad Bandwidth to Mosaic Transducer

SONG Zhe, YAN You-rong

2018, 26(5): 498-502. doi: 10.11993/j.issn.2096-3920.2018.05.019

[Abstract](855) [PDF 1491KB](598)

Abstract:
To realize low-frequency acoustic emission of small caliber underwater unmanned vehicle(UUV), further reduce the volume and mass proportion of a transducer in the UUV, and widen available frequency band of the transducer, a kind of thin-walled mosaic cylindrical transducer for the UUV was designed. Considering the limitation of the UUV on the transducer’s size and mass, the influence of height parameter of the mosaic circular ring on the electroacoustic performance of the transducer was analyzed by combination of the theoretical formula with the finite element software ANSYS. The reasonable design of the ring height can realize the coupling of the radial breathing vibration modal of the circular ring and the bending vibration modal in height direction to widen the frequency band. Thin wall design was adopted to reduce the mass and space occupancy. The vibration form and acoustic performance of the transducer in the frequency band below resonant frequency were analyzed through modal analysis. According to the simulated optimized results, a prototype of the transducer was fabricated. Tests show that in the operating frequency band from 5.5 to 33 kHz, the in-band transmitting voltage response fluctuates between 4 dB and +4 dB approximately, which is basically consistent with the simulation results. The in-band sound source level is greater than 173 dB, while in the lower frequency band from 500 Hz to 1 kHz the sound source level is higher than 144 dB, indicating a certain low-frequency acoustic emission performance. This work may provide a reference for realizing low-frequency and wide-band acoustic emission of small caliber UUV transducer.

A Shape Estimation Algorithm of Deformed Towed Array in Passive Sonar

TENG Yue-hui, ZENG Sai

2018, 26(5): 503-509. doi: 10.11993/j.issn.2096-3920.2018.05.020

[Abstract](797) [PDF 1858KB](438)

Abstract:
Towed array sonar is the main equipment to detect remote underwater targets. Its tactical maneuver may induce the shape deformation of the towed array, thus reducing the spatial processing gain and increasing the target azimuth estimation error with the towed array sonar. Therefore, a shape deformation estimation method for towed array sonar has been proposed based on parabolic model and exponential model. The shape deformation of the towed array are described by using space projection of three-dimensional curve. Exploiting the information of heading sensor and pitching sensor in the towed array, a three-dimensional array shape estimation algorithm with strong robustness is proposed. The factors of heading precision and model mismatch for the estimation performance of towed array shape parameters are analyzed. It is concluded that three-dimensional towed array shape deformation can be estimated with the presented algorithm, which breaks through the limitation of plane and micro shape deformation in the towed array.

2018 Vol. 26, No. 5

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