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Moving target localization for multistatic passive radar using delay, Doppler and Doppler rate measurements

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Journal of Systems Engineering and Electronics 2020年第5期31卷 939-949页

作者： ZHAO Yongsheng hu dexiu ZHAO Yongjun LIU Zhixin Data and Target Engineering Institute PLA Strategic Support Force Information Engineering UniversityZhengzhou 450001China

Time delay and Doppler shift between the echo signal and the reference signal are two most commonly used measurements in target localization for the passive radar. Doppler rate, which can be obtained from the extended cross ambiguity function, offers an opportunity to further enhance the localization accuracy. This paper considers using the measurement Doppler rate in addition to measurements of time delay and Doppler shift to locate a moving target. A closed-form solution is developed to accurately and efficiently estimate the target position and *** proposed solution establishes a pseudolinear set of equations by introducing some additional variables, imposes weighted least squares formulation to yield a rough estimate, and utilizes the function relation among the target location parameters and additional variables to improve the estimation accuracy. Theoretical covariance and Cramer-Rao lower bound(CRLB) are derived and compared, analytically indicating that the proposed solution attains the CRLB. Numerical simulations corroborate this analysis and demonstrate that the proposed solution outperforms existing methods.

关键词： target localization multistatic passive radar time delay Doppler shift Doppler rate

Effect of sodium alginate on phosphorus recovery by vivianite precipitation

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Journal of Environmental Sciences 2020年第7期32卷 164-169页

作者： Cong Zhang dexiu hu Ruijie Yang Zichen Liu State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi’an University of TechnologyXi’an 710048China

There are good prospects for phosphorus recovery from excess sludge by vivianite crystallization while a large number of extracellular polymeric substances in sludge will have impact on vivianite *** this study,as a representative of extracellular polymeric substance,the effect of sodium alginate(SA)on phosphorus recovery by vivianite precipitation under different initial SA concentrations(0–800 mg/L),p H values(6.5–9.0)and Fe/P molar ratios(1:1–2.4:1)was investigated using synthetic *** results showed that SA in low concentrations(≤400 mg/L)had little inhibitory effect on the phosphorus recovery ***,when the concentration of SA was larger than 400 mg/L,the phosphorus recovery rate decreased significantly with increasing SA *** inhibition rate of 800 mg/L SA was about 3 times as large as that of 400 mg/L *** was worth noting that the inhibitory effect of SA on vivianite precipitation decreased with increasing initial p H and Fe/P molar ***,SA has no obvious influence on the composition of products,but the morphology of harvested crystals was transformed from branches to plates or rods in uneven sizes.

关键词： Phosphorus recovery Excess sludge Vivianite Sodium alginate

Moving target localization in distributed MIMO radar with transmitter and receiver location uncertainties

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Chinese Journal of Aeronautics 2019年第7期32卷 1705-1715页

作者： Yongsheng ZHAO dexiu hu Yongjun ZHAO Zhixin LIU National Digital Switching System Engineering and Technological Research Center (NDSC)

In this paper, the problem of moving target localization from Bistatic Range(BR) and Bistatic Range Rate(BRR) measurements in a Multiple-Input Multiple-Output(MIMO) radar system having widely separated antennas is investigated. We consider a practically motivated scenario,where the accurate knowledge of transmitter and receiver locations is not known and only the nominal values are available for processing. With the transmitter and receiver location uncertainties,which are usually neglected in MIMO radar systems by prior studies, taken into account in the measurement model, we develop a novel algebraic solution to reduce the estimation error for moving target localization. The proposed algorithm is based on the pseudolinear set of equations and two-step weighted least squares estimation. The Cramer-Rao Lower Bound(CRLB) is derived in the presence of transmitter and receiver location uncertainties. Theoretical accuracy analysis demonstrates that the proposed solution attains the CRLB, and numerical examples show that the proposed solution achieves significant performance improvement over the existing algorithms.

关键词： Bistatic range Bistatic range rate Location uncertainty MIMO radar Target localization Two-step weighted least squares

Joint TDOA, FDOA and differential Doppler rate estimation： Method and its performance analysis

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Chinese Journal of Aeronautics 2018年第1期31卷 137-147页

作者： dexiu hu Zhen huANG Shangyu ZHANG Jianhua LU Space Technology Research Center Tsinghua University Beijing 100084 China Zhengzhou Information Technology Institute Zhengzhou 450002 China

Considering the estimation accuracy reduction of Frequency Difference of Arrival （FDOA） caused by relative Doppler companding, a joint Time Difference of Arrival （TDOA）, FDOA and differential Doppler rate estimation method is proposed and its Cramer-Rao low bound is derived in this paper. Firstly, second-order ambiguity function is utilized to reduce the dimensionality and estimate initial TDOA and differential Doppler rate. Secondly, the TDOA estimation is updated and FDOA is obtained using cross ambiguity function, in which relative Doppler com- panding is compensated by the existing differential Doppler rate. Thirdly, differential Doppler rate estimation is updated using cross estimator. Theoretical analysis on estimation variance and Cramer-Rao low bound shows that the final estimation of TDOA, FDOA and differential Doppler rate performs well at both low and high signal-noise ratio, although the initial estimation accuracy of TDOA and differential Doppler rate is relatively poor under low signal-noise ratio conditions. Simulation results finally verify the theoretical analysis and show that the proposed method can overcome relative Doppler companding problem and performs well for all TDOA, FDOA and differential Doppler rate estimation.

关键词： Differential Doppler rate Frequency difference of arrival Passive location Performance analysis Time difference of arrival

基于MLR–SARIMA模型的土石坝位移预测

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工程科学与技术 2019年第2期51卷 108-114页

作者：李斌胡德秀杨杰程琳西安理工大学水利水电学院陕西西安710048 西北旱区生态水利国家重点实验室西安理工大学陕西西安710048

为分析周期因子与时效因子分别对土石坝位移的影响,更好地掌握土石坝位移变化的成因和趋势,进行土石坝位移数据中周期成分和趋势成分的变化规律和预测方法研究。采用HP(Hodrick–Prescott)滤波将实测位移序列分解为趋势项和周期项两部分... 详细信息

为分析周期因子与时效因子分别对土石坝位移的影响,更好地掌握土石坝位移变化的成因和趋势,进行土石坝位移数据中周期成分和趋势成分的变化规律和预测方法研究。采用HP(Hodrick–Prescott)滤波将实测位移序列分解为趋势项和周期项两部分,对趋势项建立基于MLR(multiple linear regression)的预测模型,对周期项建立基于SARIMA(seasonal auto-regressive integrated moving average)的预测模型,结合以上两模型的结果对土石坝位移进行预测,即MLR–SARIMA预测模型。该模型突出了MLR模型在趋势性数据上的预测优势和SARIMA模型在周期性数据上的预测优势,且仅从实测位移数据分析预测,可适用于缺少环境量数据的情况。实测位移序列经HP滤波分解后,趋势项位移呈缓慢增长趋势,年变幅从1.42至0.51 mm逐渐降低,表明由时效因子引起的土石坝趋势性位移量逐年减小,且已趋于稳定;周期项位移具有明显年周期性,这是由于土石坝位移受到年周期性变化的水位和温度影响,年变幅约为7.00 mm,表明该土石坝位移量主要是由周期因子引起的周期性位移;该变化规律符合土石坝位移的一般变化规律,说明HP滤波可很好地提取土石坝位移数据中的周期成分和趋势成分。MLR–SARIMA模型预测结果准确,相对误差较小,均在5%以内,且均方根误差、平均绝对误差百分比和调整的平均绝对误差百分比这3个指标均优于单一SARIMA模型,表明MLR–SARIMA模型突出了其在预测周期性和趋势性数据方面的优势,可适用于土石坝位移预测。

关键词：土石坝 MLR–SARIMA模型位移预测 HP滤波

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基于脉冲串的雷达信号分选性能评估指标

信号处理 2022年第11期38卷 2350-2358页

作者：谢敏赵闯胡德秀中国人民解放军战略支援部队信息工程大学数据与目标工程学院河南郑州450001

针对目前基于脉冲的雷达信号分选性能评估指标不够全面且战术性体现不足的问题,本文将分选过程置于电子侦察流程中进行考察,基于去交错结果提炼出更契合战术性的分选性能评估指标。在评估分选性能时,以脉冲串为处理单元,重点关注辐射源... 详细信息

针对目前基于脉冲的雷达信号分选性能评估指标不够全面且战术性体现不足的问题,本文将分选过程置于电子侦察流程中进行考察,基于去交错结果提炼出更契合战术性的分选性能评估指标。在评估分选性能时,以脉冲串为处理单元,重点关注辐射源的漏检和脉冲串的虚警。此外,考察了分选出子谐波的情况和分选处理流程的时间,又从电子情报质量的角度考察了脉冲重复间隔(Pulse Repetition Interval,PRI)估计和脉冲序列匹配度。仿真实验研究了PRI抖动和脉冲丢失对分选性能评估指标的影响。仿真结果表明,所提评估指标的实验数据与PRI抖动和脉冲丢失率对分选过程的影响机理相互印证,体现了所提指标的合理性。此外,借助评估指标可以对分选过程进行精准分析,所提评估指标的有效性及全面性得到验证。

关键词：分选性能评估脉冲重复间隔分选脉冲串脉冲重复间隔抖动脉冲丢失

偏最小二乘法回归在水利工程安全监测中的应用

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农业工程学报 2007年第3期23卷 136-140页

作者：杨杰方俊胡德秀闫建文西安理工大学水利水电学院水工系西安710048 四川电力职业技术学院水利建筑系成都610072

针对常规最小二乘法回归难以有效识别和消除自变量因子间的多重相关性影响这一不足,对偏最小二乘法回归在水利工程安全监测数据分析中的应用进行了研究。采用偏最小二乘法进行回归建模分析,将模型拟合与非模型式的数据内涵分析有机结合... 详细信息

针对常规最小二乘法回归难以有效识别和消除自变量因子间的多重相关性影响这一不足,对偏最小二乘法回归在水利工程安全监测数据分析中的应用进行了研究。采用偏最小二乘法进行回归建模分析,将模型拟合与非模型式的数据内涵分析有机结合,同时实现回归建模、数据结构简化以及因子间的多重相关性分析,并通过交叉有效性检验来确保模型精度。对绕坝渗流地下水位实测资料的建模分析表明,偏最小二乘回归法能有效克服因子间的多重相关性影响,所分离出的因子变量对实测结果具有更好的物理成因解释能力,因而在水利工程安全监测及有关数据的统计分析方面具有广阔的应用前景。

关键词：偏最小二乘法多重相关性水利工程安全监测

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空间目标位置误差未知的碰撞概率算法

计算机工程与应用 2011年第33期47卷 219-221,225页

作者：吴波赵拥军胡德秀解放军信息工程大学信息工程学院郑州450002

针对航天器和空间碎片位置误差未知的情况,提出一种空间目标碰撞概率的计算方法。该方法基于正交投影变换将碰撞概率中的三维问题转化到二维进行求解,并利用变量置换的方法计算空间目标碰撞概率。讨论了位置误差椭球形状和大小变化对碰... 详细信息

针对航天器和空间碎片位置误差未知的情况,提出一种空间目标碰撞概率的计算方法。该方法基于正交投影变换将碰撞概率中的三维问题转化到二维进行求解,并利用变量置换的方法计算空间目标碰撞概率。讨论了位置误差椭球形状和大小变化对碰撞概率的影响。根据实际碰撞事例验证了其有效性。

关键词：碰撞概率空间碎片正交投影变量置换

基于FRT-MLVD的无源雷达机动目标徙动补偿算法

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通信学报 2019年第7期40卷 95-103页

作者：赵勇胜胡德秀靳科刘智鑫赵拥军战略支援部队信息工程大学数据与目标工程学院

无源雷达机动目标长时间相参积累过程中,目标的运动参数会引起距离徙动和多普勒徙动,导致回波信号能量分散和检测性能恶化。为实现含有第二加速度的变加速运动目标相参积累,提出了一种基于频域序列反转变换(FRT)和改进吕分布(MLVD)的相... 详细信息

无源雷达机动目标长时间相参积累过程中,目标的运动参数会引起距离徙动和多普勒徙动,导致回波信号能量分散和检测性能恶化。为实现含有第二加速度的变加速运动目标相参积累,提出了一种基于频域序列反转变换(FRT)和改进吕分布(MLVD)的相参积累算法。首先,利用 FRT 去除信号的距离徙动,将回波能量积累至同一距离单元;然后,利用 MLVD 对该距离单元内的回波进行处理,估计出目标加速度和第二加速度;在补偿目标的加速度和第二加速度引起的多普勒徙动后,利用 Keystone 变换(KT)校正目标速度引起的线性徙动,实现距离和速度的估计。仿真结果表明,所提算法可有效补偿无源雷达中机动目标的距离徙动和多普勒徙动,对变加速目标的积累效果和检测概率显著优于现有算法。

关键词：机动目标相参积累无源雷达频域序列反转变换改进吕分布 Keystone 变换