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REGULARIZATION APPROACH FOR FAST INTEGER AMBIGUITY RESOLUTION OF MEDIUM-LONG BASELINE GPS NETWORK RTK 被引量:4
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作者 罗孝文 欧吉坤 袁运斌 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第3期235-242,共8页
An improved method based on the Tikhonov regularization principle and the precisely known reference station coordinate is proposed to design the regularized matrix. The ill-conditioning of the normal matrix can be imp... An improved method based on the Tikhonov regularization principle and the precisely known reference station coordinate is proposed to design the regularized matrix. The ill-conditioning of the normal matrix can be improved by the regularized matrix. The relative floating ambiguity can be computed only by using the data of several epochs. Combined with the LAMBDA method, the new approach can correctly and quickly fix the integer ambiguity and the success rate is 100% in experiments. Through using measured data sets from four mediumlong baselines, the new method can obtain exact ambiguities only by the Ll-frequency data of three epochs. Compared with the existing methods, the improved method can solve the ambiguities of the medium-long baseline GPS network RTK only using L1-frequency GPS data. 展开更多
关键词 GPS network RTK integer ambiguity fast resolution
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ALGORITHM FOR AMBIGUITY RESOLUTION IN RANGE AND VELOCITY 被引量:1
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作者 张弓 朱兆达 吕波 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期219-223,共5页
For enhancing performances and increasing functions of PD radar, High PRF, medium PRF and low PRF are commonly applied into system ambiguity appeared in range and velocity in some PRF. Based on clustering, a slidin... For enhancing performances and increasing functions of PD radar, High PRF, medium PRF and low PRF are commonly applied into system ambiguity appeared in range and velocity in some PRF. Based on clustering, a sliding window correlator algorithm for resolving the radar object ambiguity in range and velocity is described. Slide window algorithm is a searching algorithm. The probability of ambiguity resolution for targets and the computational efficiency are discussed. The relations between the probability of ambiguity resolution of this algorithm and PRF, the range of interest, and the width of sliding window are analyzed. Simulational results are also given. 展开更多
关键词 PD radar ambiguity resolution sliding window CLUSTERING
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Improvement of GPS ambiguity resolution using prior height information. Part Ⅰ: The method by using height validation 被引量:5
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作者 朱建军 Rock Santerre 《Journal of Central South University of Technology》 2002年第3期186-190,共5页
It is an attractive method to combine GPS observations with the information from other surveying system to improve the ambiguity resolution. This research is conducted to investigate how to obtain the prior height inf... It is an attractive method to combine GPS observations with the information from other surveying system to improve the ambiguity resolution. This research is conducted to investigate how to obtain the prior height information in bathymetric surveying by GPS positioning and how to use the prior height information and to obtain a robust result. The authors deal with the collection and the description of the prior height and the method using height validation to improve the ambiguity resolution. The principle of the method, the relationships between the height threshold and the ambiguity search space are presented. A method to determine the threshold for the height validation is suggested. The field tests are carried out to show the feasibility of the proposed methods. 展开更多
关键词 ambiguity resolution HEIGHT VALIDATION ROBUSTNESS OTF techniques
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HIGH RESOLUTION PARAMETRIC MODELLING FOR TWO-DIMENSIONAL RADAR TARGET USING PRONY ALGORITHM 被引量:2
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作者 Wang Jun (Institute of Electronic Engineering, Chinese Academy of Engineering and Physics, Mianyang 621900) 《Journal of Electronics(China)》 2000年第1期38-45,共8页
On the conditions of low-resolution radar, a parametric model for two-dimensional radar target is described here according to the theory of electromagnetic scattering and the geometrical theory of diffraction. A high ... On the conditions of low-resolution radar, a parametric model for two-dimensional radar target is described here according to the theory of electromagnetic scattering and the geometrical theory of diffraction. A high resolution estimation algorithm to extract the model parameters is also developed by building the relation of the scattering model and Prony model. The analysis of Cramer-Rao bound and simulation show that the method here has better statistical performance. The simulated analysis also indicates that the accurate extraction of the diffraction coefficient of scattering center is restricted by signal to noise ratio, radar center frequency and radar bandwidth. 展开更多
关键词 two-dimensional RADAR SCATTERING center attributes PARAMETRIC modelling PRONY algorithm resolution
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Ambiguity Resolution in Direction of Arrival Estimation with Linear Antenna Arrays Using Differential Geometry
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作者 Alamgir Safi Muhammad Asghar Khan +4 位作者 Fahad Algarni Muhammad Adnan Aziz M.Irfan Uddin Insaf Ullah Tanweer Ahmad Cheema 《Computers, Materials & Continua》 SCIE EI 2022年第1期581-599,共19页
Linear antenna arrays(LAs)can be used to accurately predict the direction of arrival(DOAs)of various targets of interest in a given area.However,under certain conditions,LA suffers from the problem of ambiguities amon... Linear antenna arrays(LAs)can be used to accurately predict the direction of arrival(DOAs)of various targets of interest in a given area.However,under certain conditions,LA suffers from the problem of ambiguities among the angles of targets,which may result inmisinterpretation of such targets.In order to cope up with such ambiguities,various techniques have been proposed.Unfortunately,none of them fully resolved such a problem because of rank deficiency and high computational cost.We aimed to resolve such a problem by proposing an algorithm using differential geometry.The proposed algorithm uses a specially designed doublet antenna array,which is made up of two individual linear arrays.Two angle observation models,ambiguous observation model(AOM)and estimated observation model(EOM),are derived for each individual array.The ambiguous set of angles is contained in the AOM,which is obtained from the corresponding array elements using differential geometry.The EOM for each array,on the other hand,contains estimated angles of all sources impinging signals on each array,as calculated by a direction-finding algorithm such as the genetic algorithm.The algorithm then contrasts the EOM of each array with its AOM,selecting the output of that array whose EOM has the minimum correlation with its corresponding AOM.In comparison to existing techniques,the proposed algorithm improves estimation accuracy and has greater precision in antenna aperture selection,resulting in improved resolution capabilities and the potential to be used more widely in practical scenarios.The simulation results using MATLAB authenticates the effectiveness of the proposed algorithm. 展开更多
关键词 Antenna array direction of arrival ambiguity resolution doublet antenna array ambiguous observation model estimated observation model
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ALGORITHM FOR THE NOMINAL RESOLUTION IN RECTANGULAR PULSE SIGNAL USING THE AMBIGUITY MATRIX
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作者 GuoQiang TaoRan WangYue ZhouSiyong ShanTao 《Journal of Electronics(China)》 2004年第1期23-32,共10页
It is a main form using the main beamwidth of the ambiguity function to judge the signal resolution, in which the range or Doppler resolution of the signals are investigated for the targets close to each other. Howeve... It is a main form using the main beamwidth of the ambiguity function to judge the signal resolution, in which the range or Doppler resolution of the signals are investigated for the targets close to each other. However, for the pulse signal with rectangular envelope, if the nominal range resolution is calculated from the classic definition, there exists the problem of infinite integral for the high power terms of sine function, and a definite result could not be obtained. Though a definite solution of the nominal velocity resolution can be calculated from the definition, the calculation for the signal consisting of multiple-pulse, especially several periods, is very complex. The paper begins with the physical meaning of nominal resolution rather than from the definition formula to solve the problem using the ambiguity matrix, and make the calculation simplified greatly. 展开更多
关键词 Rectangular pulse Nominal resolution ambiguity matrix Sync-plus-white
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Ambiguity Resolution in English Language Processing
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作者 唐慧君 黄曦 《海外英语》 2013年第13期248-250,共3页
Language ambiguity resolution has been widely studied by psycholinguists.Studies of lexical ambiguity resolution,syntactic ambiguity resolution and anaphoric ambiguity resolution have showed different results.One acco... Language ambiguity resolution has been widely studied by psycholinguists.Studies of lexical ambiguity resolution,syntactic ambiguity resolution and anaphoric ambiguity resolution have showed different results.One account assumes that ambiguity resolution involves"competition"of analysis which causes processing difficulties.The other account claims that an initial analysis is adopt and"reanalysis"occurs when the initial analysis turns out to be implausible. 展开更多
关键词 ambiguity resolution COMPETITION REANALYSIS
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Analysis of Resolution of Bistatic SAR 被引量:1
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作者 Tian-Ge Shao Jian-Guo Wang 《Journal of Electronic Science and Technology of China》 2007年第3期255-259,共5页
In this paper, the spatial resolutions at different directions of bistatic synthetic aperture radar (BiSAR) have been derived from the ambiguity function. Compared with monostatic signal to noise ratio, BiSAR's res... In this paper, the spatial resolutions at different directions of bistatic synthetic aperture radar (BiSAR) have been derived from the ambiguity function. Compared with monostatic signal to noise ratio, BiSAR's resolutions of a fixed point target are varying with slow time since BiSAR system is space-variant. Constraints for the assumption of space-invariant bistatic topology are proposed in the paper. Moreover, under the assumption of invariance, the change of resolutions at different point in the image scene is taken into account, and we have specified two key parameters that affect resolutions directly and analyzed the way how they influence on the resolutions. 展开更多
关键词 ambiguity function bistatic SAR resolution.
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Multi-dimensional ambiguity function for subarray-based space-time coding radar
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作者 LAN Lan LIAO Guisheng +1 位作者 XU Jingwei WANG Hanbing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期886-896,共11页
Space-time coding radar has been recently proposed and investigated.It is a radar framework which can perform transmit beamforming at the receiver.However,the range resolution decreases when the number of the transmit... Space-time coding radar has been recently proposed and investigated.It is a radar framework which can perform transmit beamforming at the receiver.However,the range resolution decreases when the number of the transmit element increases.A subarray-based space-time coding(sub-STC)radar is explored to alleviate the range resolution reduction.For the proposed radar configuration,an identical waveform is transmitted and it introduces a small time offset in different subarrays.The multidimensional ambiguity function of sub-STC radar is defined by considering resolutions in multiple domains including the range,Doppler,angle and probing direction.Analyses on properties of the multi-dimensional ambiguity function of the sub-STC radar with regard to the spatial coverage,resolution performance and low sidelobes are also given.Results reveal that the range resolution and low sidelobes performance are improved with the proposed approach. 展开更多
关键词 SPACE-TIME coding RADAR MULTI-DIMENSIONAL ambiguity function range resolution wide spatial coverage SUBARRAY SIDELOBE
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Resolution analysis of GEO spaceborne-airborne bistatic SAR based on sliding spotlight mode 被引量:1
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作者 Meng Lian Yicheng Jiang Bin Hu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期352-361,共10页
For a synthetic aperture radar(SAR) system mounted on a geostationary Earth orbit(GEO) satellite, the track can be curvilinear. Thus, a bistatic SAR system based up on geostationary transmitter and "receive-only... For a synthetic aperture radar(SAR) system mounted on a geostationary Earth orbit(GEO) satellite, the track can be curvilinear. Thus, a bistatic SAR system based up on geostationary transmitter and "receive-only" SAR system onboard airplanes, namely GEO spaceborne-airborne bistatic(GEO SA-Bi SAR), is significantly different from the traditional bistatic SAR. This paper mainly studies the resolution characteristic of the sliding spotlight GEO SA-Bi SAR system. Firstly, the common azimuth coverage and coherent accumulated time are theoretically analyzed in detail. Then,based on the gradient method, the accurate two dimensional resolution of a GEO SA-Bi SAR system is analytically calculated. Finally, the simulation data show the correctness and effectiveness of the proposed resolution analysis method. 展开更多
关键词 sliding spotlight mode geostationary Earth orbit(GEO) synthetic aperture radar(SAR) GEO spaceborneairborne bistatic SAR(GEO SA-Bi SAR) two-dimensional resolution
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ACCELERATION AMBIGUITY FUNCTION OF RADAR SIGNALS AND ITS APPLICATION
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作者 Zhao Hongzhong Zhou Jianxiong Li Weimin Fu Qiang (The ATR Laboratory of National University of Defence Technology, Changsha 410073) 《Journal of Electronics(China)》 2003年第6期401-406,共6页
High acceleration of radar targets is analyzed using Acceleration Ambiguity Function (AAF). The acceleration resolution based on AAF is defined. The AAF and acceleration resolution of rectangle pulse signal are deriva... High acceleration of radar targets is analyzed using Acceleration Ambiguity Function (AAF). The acceleration resolution based on AAF is defined. The AAF and acceleration resolution of rectangle pulse signal are derivated and the conclusion that its acceleration resolution is in inverse proportion with the square of its duration is drawn. In the end, these conclusions are applied to the parameter designing and performance evaluation for a certain type of pulse Doppler radar. 展开更多
关键词 Acceleration ambiguity Function(AAF) Acceleration resolution Doppler radar Accumulating time Maneuvering target
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Hybrid analytical resolution approach based on ambiguity function for attitude determination 被引量:8
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作者 Wen-rui JIN Chuan-run ZHAI +2 位作者 Li-duan WANG Yan-hua ZHANG Xing-qun ZHAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第7期1038-1048,共11页
When satellite navigation receivers are equipped with multiple antennas, they can deliver attitude information. In previous researches, carrier phase differencing measurement equations were built in the earth-centered... When satellite navigation receivers are equipped with multiple antennas, they can deliver attitude information. In previous researches, carrier phase differencing measurement equations were built in the earth-centered, earth-fixed (ECEF) co- ordinate, and attitude angles could be obtained through the rotation matrix between the body frame (BF) and the local level frame (LLF). Different from the conventional methods, a hybrid algorithm is presented to resolve attitude parameters utilizing the single differencing (SD) carrier phase equations established in LLF. Assuming that the cycle integer ambiguity is known, the measure- ment equations have attitude analytical resolutions by using simultaneous single difference equations for two in-view satellites. In addition, the algorithm is capable of reducing the search integer space into countable 2D discrete points and the ambiguity function method (AFM) resolves the ambiguity function within the analytical solutions space. In the case of frequency division multiple access (FDMA) for the Russian Global Orbiting Navigation Satellite System (GLONASS), a receiver clock bias estimation is employed to evaluate its carrier phase. An evaluating variable and a weighted factor are introduced to assess the integer ambiguity initialization. By static and dynamic ground experiments, the results show that the proposed approach is effective, with enough accuracy and low computation. It can satisfy attitude determination in cases of GPS alone and combined with GLONASS. 展开更多
关键词 Global positioning system (GPS) Russian Global Orbiting Navigation Satellite System (GLONASS) Analytical resolution Attitude determination ambiguity function method (AFM)
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Precise orbit determination of Haiyang‑2D using onboard BDS‑3 B1C/B2a observations with ambiguity resolution 被引量:3
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作者 Kecai Jiang Wenwen Li +4 位作者 Min Li Jianghui Geng Haixia Lyu Qile Zhao Jingnan Liu 《Satellite Navigation》 SCIE EI CSCD 2023年第3期167-184,共18页
The Haiyang-2D altimetry mission of China is one of the first Low Earth Orbit(LEO)satellites that can receive new B1C/B2a signals from the BeiDou-3 Navigation Satellite System(BDS-3)for Precise Orbit Determination(POD... The Haiyang-2D altimetry mission of China is one of the first Low Earth Orbit(LEO)satellites that can receive new B1C/B2a signals from the BeiDou-3 Navigation Satellite System(BDS-3)for Precise Orbit Determination(POD).In this work,the achievable accuracy of the single-receiver ambiguity resolution for onboard LEO satellites is studied based on the real measurements of new BDS-3 frequencies.Under normal conditions,six BDS-3 satellites on average are visible.However,the multipath of the B1C/B2a code observations presents some patchy patterns that cause near-field variations with an amplitude of approximately 40 cm and deteriorate the ambiguity-fixed rate.By modeling those errors,for the B2a code,a remarkable reduction of 53%in the Root Mean Square(RMS)is achieved at high elevations,along with an increase of 8%in the ambiguity-fixed rates.Additionally,an analysis of the onboard antenna’s phase center offsets reveals that when compared to the solutions with float ambiguities,the estimated values in the antenna’s Z direction in the solutions with fixed ambiguities are notably smaller.The independent validation of the resulting POD using satellite laser ranging at 16 selected high-performance stations shows that the residuals are reduced by a minimum of 15.4%for ambiguity-fixed solutions with an RMS consistency of approximately 2.2 cm.Furthermore,when compared to the DORIS-derived orbits,a 4.3 cm 3D RMS consistency is achieved for the BDS-3-derived orbits,and the along-track bias is reduced from 2.9 to 0.4 cm using ambiguity fixing. 展开更多
关键词 ambiguity resolution B1C/B2a Onboard BDS-3 Precise orbit determination Haiyang-2D
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Performance investigation of LAMBDA and bootstrapping methods for PPP narrow-lane ambiguity resolution
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作者 Omer Faruk Atiz Sermet Ogutcu +2 位作者 Salih Alcay Pan Li Ilkay Bugdayci 《Geo-Spatial Information Science》 SCIE EI CSCD 2021年第4期604-614,共11页
Precise point positioning with ambiguity resolution(PPP-AR)is a powerful tool for geodetic and time-constrained applications that require high precision.The performance of PPP-AR highly depends on the reliability of t... Precise point positioning with ambiguity resolution(PPP-AR)is a powerful tool for geodetic and time-constrained applications that require high precision.The performance of PPP-AR highly depends on the reliability of the correct integer carrier-phase ambiguity estimation.In this study,the performance of narrow-lane ambiguity resolution of PPP using the Least-squares AMBiguity Decorrelation(LAMBDA)and bootstrapping methods is extensively investigated using real data from 55 IGS stations over one-month in 2020.Static PPP with 24-,12-,8-,4-,2-,1-and½-h sessions using two different cutoff angles(7°and 30°)was conducted with three PPP modes:i.e.ambiguity-float and two kinds of ambiguity-fixed PPP using the LAMBDA and bootstrapping methods for narrow-lane AR,respectively.The results show that the LAMBDA method can produce more reliable results for 2 hour and shorter observation sessions com-pared with the bootstrapping method using a 7°cutoff angle.For a 30°cutoff angle,the LAMBDA method outperforms the bootstrapping method for observation sessions of 4 h and less.For long observation times,the bootstrapping method produced much more accurate coordinates compared with the LAMBDA method without considering the wrong fixes cases.The results also show that occurrences of fixing the wrong integer ambiguities using the bootstrapping method are higher than that of the LAMBDA method. 展开更多
关键词 ambiguity resolution narrow-lane Precise point positioning(PPP) LAMBDA BOOTSTRAPPING
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Precise orbit determination for LEO satellites:single-receiver ambiguity resolution using GREAT products
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作者 Xingxing Li Yujie Qin +4 位作者 Keke Zhang Jiaqi Wu Wei Zhang Qian Zhang Hongmin Zhang 《Geo-Spatial Information Science》 SCIE EI CSCD 2022年第1期63-73,共11页
In recent years,the large Low Earth Orbit(LEO)constellations have become a hot topic due to their great potential to improve the Global Navigation Satellite Systems(GNSS)positioning performance.One of the important fo... In recent years,the large Low Earth Orbit(LEO)constellations have become a hot topic due to their great potential to improve the Global Navigation Satellite Systems(GNSS)positioning performance.One of the important focus is how to obtain the accurate and reliable orbits for these constellations with dozens of LEO satellites.The GNSS-based Precise Orbit Determination(POD)will be exclusively performed to achieve this goal,where the Integer Ambiguity Resolution(IAR)plays a key role in acquiring high-quality orbits.In this study,we present a comprehensive analysis of the benefit of the single-receiver IAR in LEO POD and discuss its implication for the future LEO constellations.We perform ambiguity-fixed LEO POD for four typical missions,including Gravity Recovery and Climate Experiment(GRACE)Follow-On(GRACE-FO),Swarm,Jason-3 and Sentinel-3,using the Uncalibrated Phase Delay(UPD)products generated by our GREAT(GNSS+REsearch,Application and Teaching)software.The results show that the ambiguity fixing processing can significantly improve the accuracy of LEO orbits.There are negligible differences between our UPD-based ambiguity-fixed orbits and those based on the Observable Signal Bias(OSB)and Integer Recovery Clock(IRC)products,indicating the good-quality of UPD products we generated.Compared to the float solution,the fixed solution presents a better consistency with the external precise science orbits and the largest accuracy improvement of 5 mm is achieved for GRACE-FO satellites.Meanwhile,the benefit can be observed in laser ranging residuals as well,with a Standard Deviation(STD)reduction of 3–4 mm on average for the fixed solutions.Apart from the absolute orbits,the relative accuracy of the space baseline is also improved by 20–30%in the fixed solutions.The result demonstrates the superior performance of the ambiguity-fixed LEO POD,which appears as a particularly promising technique for POD of future LEO constellations. 展开更多
关键词 Precise orbit determination single-receiver ambiguity resolution onboard GPS observation LEO
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Indirect-Inversion A lgorithm via Precise Integration for Ill-Conditioned Matrix in Ambiguity Resolution
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作者 ZHAO Fang SUN Jin +1 位作者 ZHAO Jianjun YANG Libin 《Journal of Shanghai Jiaotong university(Science)》 EI 2020年第6期762-768,共7页
Global navigation satellite system(GNSS)positioning depends on the correct integer ambiguity resolu-tion(AR).If the double difference equation for solving the float solution remains il-conditioned,often happening due ... Global navigation satellite system(GNSS)positioning depends on the correct integer ambiguity resolu-tion(AR).If the double difference equation for solving the float solution remains il-conditioned,often happening due to the environment complexity and the equipment mobility,the corrcct AR is difficult to achieve.Concern-ing the il-conditioned problem,methods of modifying the equation cofficient matrix are widely applied,whose effects are heavily dependent on modifying parameters.Besides,the direct inversion of the il-conditioned coef-ficient matrix can lead to a reduction in the accuracy and stability of the float solution.To solve the problem of il-conditioned matrix inversion and further improve the accuracy,the present study for the first time proves the positive definite symmetry of the coefficient matrix in AR model and employs precise integration method to the indirect inverse of cofficient matrix.AR model for the GNSS positioning and the general resolving strate-gies introduction are briefly introduced.An indirect-inversion algorithm via precise integration for il-conditioned coefficient matrix is proposed.According to the simulations and comparisons,the proposed strategy has higher precision and stability on foat solution,and less dependence on modifying parameters. 展开更多
关键词 il-condition indirect-inversion ambiguity resolution precise integrat ion global navigation satellite system positioning
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基于韵律的英语介词短语挂靠歧义消解研究 被引量:1
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作者 何享 吴明军 王青 《北京第二外国语学院学报》 北大核心 2024年第3期132-147,共16页
在言语交际过程中,说话人口语表达的韵律线索对交际双方的语言理解发挥着重要作用。为了深入了解中国英语学习者英语口语产出的韵律线索与预期表达含义之间的相关性,本文以中国大学英语学习者为研究对象,采用基于情境的半开放式口语产... 在言语交际过程中,说话人口语表达的韵律线索对交际双方的语言理解发挥着重要作用。为了深入了解中国英语学习者英语口语产出的韵律线索与预期表达含义之间的相关性,本文以中国大学英语学习者为研究对象,采用基于情境的半开放式口语产出任务,考察在特定的情境化实验条件下,被试对英语介词短语挂靠造成的歧义句的朗读任务完成情况。研究结果表明:中国大学英语学习者具有对口语韵律特征与句法结构之间关系的潜在敏感性,能够通过口语的韵律停顿和音高重音实现对英语介词短语动、名词挂靠引起的歧义的消解。本研究结果进一步证实了英语口语韵律特征与预期含义之间的相互关系,凸显了韵律训练在大学英语课堂教学中的重要性,为高校英语听说及阅读教学实践的开展提供了参考建议。 展开更多
关键词 歧义消解 介词短语挂靠 韵律线索 情境化语境 韵律句法
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嵌套阵的疏密子阵融合波达方向估计方法
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作者 王娜 赵宣植 +1 位作者 刘增力 侯书画 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第3期607-614,共8页
为有效利用嵌套阵包含疏密子阵的几何结构以提高估计性能,本文提出一种在2子阵上分别测向再融合的波达方向估计方法。通过理论分析和实际案例阐明融合嵌套阵的两子阵测向结果可以消除信源角度估计模糊,且不会出现互质阵解模糊时伴随的... 为有效利用嵌套阵包含疏密子阵的几何结构以提高估计性能,本文提出一种在2子阵上分别测向再融合的波达方向估计方法。通过理论分析和实际案例阐明融合嵌套阵的两子阵测向结果可以消除信源角度估计模糊,且不会出现互质阵解模糊时伴随的匹配错误。利用无需谱峰搜索的求根多重信号分类方法在嵌套阵2子阵上求解测向结果,若稀疏子阵间距为N倍半波长,推导出对其复根开N次方可获含模糊角的高精度估计,再结合最小方差准则与精度较低但无模糊的密集子阵测向结果进行融合,最终得到高精度的波达方向估计。与嵌套阵已有算法相比,该算法提高了波达方向估计精度和分辨率,由于无需2子阵协方差降低了计算量,且能够支持嵌套阵的分布式配置。仿真结果验证了所提算法的有效性。 展开更多
关键词 嵌套阵列 求根多重信号分类 方差融合 疏密子阵 波达方向估计 稀疏子阵 密集子阵 解模糊
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基于Hatch滤波的改进矩阵变换法在BDS多频模糊度解算中的应用
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作者 刘国超 姜凯华 +1 位作者 黄文嘉 张莹 《工程勘察》 2024年第7期49-54,共6页
长基线条件下,空间相关性弱,电离层延迟残差和噪声影响变大,致使矩阵变换法模糊度解算过程中,窄巷组合受噪声影响大,单历元模糊度解算成功率低。因此,削弱电离层残差及噪声影响可以一定程度提高模糊度解算成功率。本文在分析矩阵变换算... 长基线条件下,空间相关性弱,电离层延迟残差和噪声影响变大,致使矩阵变换法模糊度解算过程中,窄巷组合受噪声影响大,单历元模糊度解算成功率低。因此,削弱电离层残差及噪声影响可以一定程度提高模糊度解算成功率。本文在分析矩阵变换算法基础上,利用Hatch滤波有效抑制伪距测量噪声和多径效应特点,结合弱电离层、低噪声的载波组合,通过相位平滑伪距代替组合伪距值参与解算,从而削弱电离层残差及观测噪声影响。通过实测数据分析,本文算法可有效提高矩阵变换法模糊度解算成功率。 展开更多
关键词 模糊度 BDS HATCH滤波 矩阵变换 载波相位平滑伪距
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一种针对机动目标的解速度模糊新算法
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作者 王建强 黄金杰 《现代信息科技》 2024年第12期61-65,共5页
解速度模糊是脉冲多普勒雷达中需要解决的重要问题,通常的解速度模糊算法皆未考虑加速度信息,当雷达跟踪火箭弹等长助推段目标时存在速度解算误差大或无法解算、不能有效预测目标速度信息等问题。针对上述情况,提出一种面向加速度目标... 解速度模糊是脉冲多普勒雷达中需要解决的重要问题,通常的解速度模糊算法皆未考虑加速度信息,当雷达跟踪火箭弹等长助推段目标时存在速度解算误差大或无法解算、不能有效预测目标速度信息等问题。针对上述情况,提出一种面向加速度目标的解速度模糊算法。计算机仿真及雷达模拟数据表明,该方法对长助推段目标速度、加速度解算准确度高,对传统目标兼容性良好。该文还给出了新算法的工程实现方法。 展开更多
关键词 脉冲多普勒雷达 解速度模糊 速度 加速度
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