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基于向量投影的立体阵定位算法

电子与信息学报 2024年第1期46卷 31-40页

作者：孙大军蔡珩郑翠娥程驰宇哈尔滨工程大学水声技术全国重点实验室哈尔滨150001 海洋信息获取与安全工信部重点实验室(哈尔滨工程大学)工业和信息化部哈尔滨150001 哈尔滨工程大学水声工程学院哈尔滨150001

传统适配立体阵型的超短基线定位算法计算量大、定位误差难以通过解析式精确表征。针对这些问题,该文提出基于向量投影的立体阵定位算法,从向量投影的角度构建立体阵中各基线向量与目标方位之间的观测方程,实现对传统算法定位模型的简... 详细信息

传统适配立体阵型的超短基线定位算法计算量大、定位误差难以通过解析式精确表征。针对这些问题,该文提出基于向量投影的立体阵定位算法,从向量投影的角度构建立体阵中各基线向量与目标方位之间的观测方程,实现对传统算法定位模型的简化。该文算法通过求解线性方程组即可实现对目标方位的估计,时间复杂度远小于传统算法。此外,基于该文算法简洁的观测方程,给出了适配立体阵的定位误差精确解析表征。仿真结果表明,该文算法消耗的运算时间远小于传统算法,且定位误差变化规律与基于理论解析式得到的结论相符。湖试试验结果表明,该文算法的定位精度与传统算法几乎一致,且计算效率更高。

关键词：超短基线定位立体阵向量投影

Improvement of Seafloor Positioning Through Correction of Sound Speed Profile Temporal Variation

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 1099-1101页

作者： Miao Yu Kuijie Cai Cuie Zheng dajun sun Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China College of Mathematical Sciences Harbin Engineering UniversityHarbin 150001China

Dear Editor,This letter proposes a high-precision seafloor transponder positioning method based on the correction of sound speed profile(SSP)temporal *** the proposed method,the ocean sound speed error is modeled as the temporal variation of a background SSP,and the linearized expression of the acoustic travel time with respect to the sound speed coefficient is derived based on the ray acoustic ***,the proposed method introduces the constraint of acoustic ranging observations between seafloor transponders and determines the weights of travel time and ranging observations using Akaike’s Bayesian information criterion(ABIC)to reduce the positioning error caused by the correlation between sound speed and position *** experimental results in the South China Sea show that the proposed method performs better than the global navigation satellite system-acoustic ranging combined positioning solver(GARPOS)[1],in terms of rigid distance errors and long baseline positioning accuracy.

关键词： ocean travel sound

Rapid calibration method for rank defect marine geodetic station network

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Chinese Journal of Acoustics 2023年第4期42卷 434-449页

作者： sun dajun OUYANG Yujie HAN Yunfeng National Key Laboratory of Underwater Acoustic Technology Harbin Engineering UniversityHarbin 150001 Key Laboratory of marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001

A rapid calibration method for marine geodetic control networks based on the combination of beacon mutual ranging information and absolute coordinate information is *** with existing methods, the rapid calibration method reduces the initial condition restriction of free net adjustment, the number of absolute calibration points is reduced by more than 50%, and the calibration efficiency and absolute coordinate precision are significantly improved. In addition, several typical formations under ideal conditions are proposed by analyzing the formations and absolute calibration points. The shallow water test results show that the calibration efficiency is improved by 50% when the calibration precision of the reference network is greater than 0.2 m.

关键词： formations marine shallow

Small moving target interference suppression detection method in space-time Doppler frequency shift domain

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Chinese Journal of Acoustics 2023年第1期42卷 1-21页

作者： sun dajun HOU Kaiyang TENG Tingting MEI Jidan LIU Huimin LI Yecheng Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001 East China Research Institute of Electronic Engineering Hefei 230088 The 54thResearch Institute of China Electronics Technology Group Corporation Shijiazhuang 050081

Active sonar can separate clutter,reverberation,and moving targets in the Doppler frequency shift domain using Doppler sensitive signals,but time and Doppler leakages of strong interference can inundate weak targets at low signal-to-interference ***,a small moving target interference suppression detection method based on an adaptive least mean square(LMS)algorithm and wide-band ambiguity function(WAF)is ***,an adaptive notch filter based on LMS is used to suppress interference in the spatial Doppler frequency shift domain and then WAF used to detect targets in the fast-time Doppler frequency shift *** simulation and pool experiments are performed and the results demonstrated that the proposed method effectively suppress strong interference and accurately estimate the target delay and Doppler *** 13 dB of interference suppression is observed in *** addition,the system is able to tolerate interference fluctuations with normalized amplitude fluctuation variance less than 0.5 and improve the active detection capacity for small moving targets.

关键词： Small moving method

A Symbol-Based Passband Doppler Tracking and Compensation Algorithm for Underwater Acoustic DSSS Communications

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Journal of Communications and Information Networks 2020年第2期5卷 168-176页

作者： dajun sun Xiaoping Hong Hongyu Cui Lu Liu College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(HEU) Ministry of Industry and Information TechnologyHarbin 150001China

In this paper,we consider the problem of Doppler tracking and compensation for a direct sequence spread spectrum(DSSS)signal in underwater acoustic(UWA)*** the dynamic property of the UWA channel and the long duration of DSSS signals result in significant Doppler spread that severely distorts the propagated signal,Doppler tracking and compensation are *** on the ultra-wideband property of UWA signal,the Doppler spread not only results in the frequency shift,but also changes the signal ***,the accurate estimation of the signal expansion/compression in the time domain can reflect the Doppler ***,we present a Doppler tracking and compensation algorithm for a DSSS signal operating on the correlation output of passband signal at a symbol-by-symbol *** that the carrier frequency of UWA communication is around several kilohertz,and thus the time delay estimation can be performed on the passband to improve the ***,the prior information of Doppler limit is used to refine the resolution of delay estimation and achieve sequential *** compensate the correlation magnitude distortion induced by the velocity variation,the local reference signal is selected adaptively based on the filtered Doppler *** results demonstrate that the proposed passband Doppler tracking algorithm achieves a superior performance compared with the conventional receiver.

关键词： UWA communications DSSS passband Doppler tracking and compensation three-point interpolation

A Block Parallel l_0-Norm Penalized Shrinkage and Widely Linear Affine Projection Algorithm for Adaptive Filter

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China Communications 2017年第1期14卷 86-97页

作者： Youwen Zhang Shuang Xiao Lu Liu dajun sun Acoustic Science and Technology Laboratory Harbin Engineering University Harbin 150001 China College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China

To improve the identification capability of AP algorithm in time-varying sparse system, we propose a block parallel l_0-SWL-DCD-AP algorithm in this paper. In the proposed algorithm, we first introduce the l_0-norm constraint to promote its application for sparse system. Second, we use the shrinkage denoising method to improve its track ability. Third, we adopt the widely linear processing to take advantage of the non-circular properties of communication signals. Last, to reduce the high computational complexity and make it easy to implemented, we utilize the dichotomous coordinate descent(DCD) iterations and the parallel processing to deal with the tapweight update in the proposed algorithm. To verify the convergence condition of the proposed algorithm, we also analyze its steadystate behavior. Several simulation are done and results show that the proposed algorithm can achieve a faster convergence speed and a lower steady-state misalignment than similar APA-type algorithm. When apply the proposed algorithm in the decision feedback equalizer(DFE), the bite error rate(BER) decreases obviously.

关键词： signal processing adaptive algorithm LMS l0-norm shrinkage linear DCD

Seafloor geodetic network establishment and key technologies

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Science China Earth Sciences 2020年第8期63卷 1188-1198页

作者： Yuanxi YANG Yanxiong LIU dajun sun Tianhe XU Shuqiang XUE Yunfeng HAN Anmin ZENG State Key L aboratory of Geo-Information Engineering Xi'an Research Institute of Surveying and MappingXi'an 710054China First Institute of Oceanography Ministry of Natural ResourceQingdao 266061China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Institute of Space Sciences Shandong UniversityWeihai 264209China Chinese Academy of Surveying and Mapping Beijing 100830China

Seafloor geodetic network construction involves the development of geodetic station shelter, network configuration design, location selection and layout, surveying strategy, observation model establishment and optimization, data processing strategy and so on. This paper tries to present main technological problems involved in the seafloor geodetic network construction, and seek the technically feasible solutions. Basic conceptions of developing seafloor geodetic station shelters for shallow sea and deep-sea are described respectively. The overall criteria of seafloor geodetic network construction for submarine navigation and those of network design for crustal motion monitoring are both proposed. In order to enhance application performances of the seafloor geodetic network, the seafloor network configuration should prefer a symmetrical network structure. The sea surface tracking line measurements for determining the seafloor geodetic station position should also adopt an approximately symmetrical configuration, and we recommend circle tracking line observations combined with cross-shaped line(or double cross-shape line) observations for the seafloor positioning mode. As to the offset correction between the Global Navigation Satellite System antenna phase center and the acoustic transducer, it is recommended to combine the calibration through external measurements and model parameter estimation. Besides, it is suggested to correct the sound speed error with a combination of observation value correction and parameterized model correction, and to mainly use the model correction to reduce the influence of acoustic ray error on the seafloor positioning. Following the proposed basic designs, experiments are performed in shallow sea area and deep-sea area respectively. Based on the developed seafloor geodetic shelter and sufficient verification in the shallow sea experiment, a long-term seafloor geodetic station in the deep-sea area of 3000 m depth was established for the

关键词： Seafloor geodesy Seafloor geodetic network Seafloor shelter Undersea navigation Acoustic positioning

High-resolution topography measurement of PACMANUS and DESMOS hydrothermal fields using a ROV in Manus basin

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Science Bulletin 2016年第15期61卷 1154-1156页

作者： Xiaochuan Ma Jun Yan Zhendong Luan Xin Zhang Cui-E Zheng dajun sun Institute of Oceanology Chinese Academy of Sciences KeyLaboratory of Marine Geology and EnvironmentQingdao 266071 China Harbin Engineering University Ringgold Standard Institution College of Underwater Acoustic Engineering Harbin 150001China

In China,the lack of high-resolution topographical data from small target areas limits our understanding of deep sea ***,the high-resolution topography of the PACMANUS hydrothermal field and the DESMOS hydrothermal field were measured using a remotely operated underwater vehicle(ROV)with a multibeam system.A composition positioning system on the ROV provided high positioning accuracy(greater than 0.5 m).The data show that four knolls develop in the PACMANUS field on the crest of the Pual ***

关键词：高分辨率地形测量 ROV 热场海盆组合定位系统目标区域多波束系统

Crosslinked hydrogels--a promising class of insoluble solid molecular dispersion carriers for enhancing the delivery of poorly soluble drugs

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Acta Pharmaceutica Sinica B 2014年第1期4卷 26-36页

作者： dajun D.sun Ping I.Lee Department of Pharmaceutical Sciences Leslie Dan Faculty of PharmacyUniversity of TorontoToronto M5S 3M2OntarioCanada

Water-insoluble materials containing amorphous solid dispersions(ASD)are an emerging category of drug carriers which can effectively improve dissolution kinetics and kinetic solubility of poorly soluble *** based on water-insoluble crosslinked hydrogels have unique features in contrast to those based on conventional water-soluble and water-insoluble *** example,solid molecular dispersions of poorly soluble drugs in poly(2-hydroxyethyl methacrylate)(PHEMA)can maintain a high level of supersaturation over a prolonged period of time via a feedback-controlled diffusion mechanism thus avoiding the initial surge of supersaturation followed by a sharp decline in drug concentration typically encountered with ASDs based on water-soluble *** creation of both immediate-and controlled-release ASD dosage forms is also achievable with the PHEMA based *** far,ASD systems based on glassy PHEMA have been shown to be very effective in retarding precipitation of amorphous drugs in the solid state to achieve a robust physical *** review summarizes recent research efforts in investigating the potential of developing crosslinked PHEMA hydrogels as a promising alternative to conventional water-soluble ASD carriers,and a related finding that the rate of supersaturation generation does affect the kinetic solubility profiles implications to hydrogel based ASDs.

关键词： Amorphous solid dispersions Crosslinked hydrogels Poly(2-hydroxyethylmethacrylate) Supersaturation Kinetic solubility