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中国古典园林中借“别有洞天”营造“转”空间的造景手法 被引量:3
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作者 李飞 《华中建筑》 2010年第4期136-139,共4页
"别有洞天"是中国古典园林中营造"转"空间的特殊的造景主题之一。该文从宏观和微观两个方面论述了"别有洞天"的地宜条件的特殊利用,同时提出借"别有洞天"营造"转"空间的造景手法,如... "别有洞天"是中国古典园林中营造"转"空间的特殊的造景主题之一。该文从宏观和微观两个方面论述了"别有洞天"的地宜条件的特殊利用,同时提出借"别有洞天"营造"转"空间的造景手法,如框景提示转折空间、加强空间对比等,也提出某些未以"别有洞天"为景名的景点也可以利用上述方法创造"别有洞天"的意境,如加强空间序列的收放对比、起伏对比、转折对比等,这些设计手法对现代风景园林中"转"空间的设计具有极好的启示作用。 展开更多
关键词 古典园林 “别有洞天” “转”空间 造景手法
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Neural Network Method for Colorimetry Calibration of Video Cameras 被引量:2
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作者 周双全 赵达尊 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期31-36,共6页
To transfer the color data from a device (video camera) dependent color space into a device? independent color space, a multilayer feedforward network with the error backpropagation (BP) learning rule, was regarded ... To transfer the color data from a device (video camera) dependent color space into a device? independent color space, a multilayer feedforward network with the error backpropagation (BP) learning rule, was regarded as a nonlinear transformer realizing the mapping from the RGB color space to CIELAB color space. A variety of mapping accuracy were obtained with different network structures. BP neural networks can provide a satisfactory mapping accuracy in the field of color space transformation for video cameras. 展开更多
关键词 color space transformation neural network color video camera
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Study on Tri-Stimulus Transformation 被引量:2
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作者 周双全 赵达尊 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期37-44,共8页
To decrease number of samples for the implementation of color space transformation, a method for modeling the chromatic characterization of video cameras was proposed. An additional transformation was required to pred... To decrease number of samples for the implementation of color space transformation, a method for modeling the chromatic characterization of video cameras was proposed. An additional transformation was required to predict output RGB values for an input color. This additional transformation was based on spectral reflectance relationship. The transformed color coordinates were taken as inputs of a multilayer neural network. Based on network outputs, the RGB values to be predicted were calculated. Experimental results were given to illustrate the performance of the method. Even though much less number of training samples are used, this method can also perform well on this color space transformation. 展开更多
关键词 color space transformation colorimetry model neural network cameras
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A Study on Vertical Spatial Transfer of Cultivated Land in Yunnan Province from 1986 to 2008 被引量:8
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作者 童绍玉 鲁永新 《Agricultural Science & Technology》 CAS 2011年第1期127-132,共6页
Based upon ArCGIS,the vertical spatial transfer law of cultivated land in Yunnan was studied through referring to three periods of remote sensing data of Land-Use and Land-Cover Change(LUCC) in Yunnan in 1986,1995 a... Based upon ArCGIS,the vertical spatial transfer law of cultivated land in Yunnan was studied through referring to three periods of remote sensing data of Land-Use and Land-Cover Change(LUCC) in Yunnan in 1986,1995 and 2000,Digital Elevation Model(DEM) of Yunnan Province and LUCC data in Yunnan from 2000 to 2008.The main factors that promote vertical spatial transfer law of cultivated land were analyzed by using SPSS,and the influence of policies and government acts upon the change of cultivated land was clarified.The findings indicated that for Yunnan cultivated land there is a trend that in the vertical direction steep slope areas and gentle slope areas divert into mid-slope areas.The primary factor influencing the vertical spatial transfer of cultivated land was policies and government acts.Also,the gradient of ground,total population and number of agriculture employed persons were also main factors in influencing the change of cultivated land,whose influence was obviously below policies and government acts. 展开更多
关键词 Cultivated land Vertical Spatial Transfer Driving factors Plicies Yunnan Province
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A novel method to improve spatial resolution of acousto-optic deflector 被引量:6
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作者 WEN Tao ZHUANG Zhao-wen WEI Ji-bo MA Dong-tang 《Optoelectronics Letters》 EI 2006年第1期34-36,共3页
In this paper, a novel method of laser beam deflecting is introduced to improve the spatial resolution of an acoustic-optic deflector (AOD). We use double AOD (DAOD) to control laser beam. Compared with single AOD, th... In this paper, a novel method of laser beam deflecting is introduced to improve the spatial resolution of an acoustic-optic deflector (AOD). We use double AOD (DAOD) to control laser beam. Compared with single AOD, the double AOD can improve speed and precision of target tracking and pointing significantly. Finally, a method of calculating the static and dynamic number of resolvable points (NRP) is provided, and it is supported by the experimental data excellently. 展开更多
关键词 光学偏 空间分辨率 激光束 靶点轨迹
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Darboux Transformations for Space-Like Isothermic Surfaces in R^m,1 被引量:4
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作者 ZUODa-Feng CHENQing CHENGYi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期816-820,共5页
In this paper,by using the G_(m,1)~(1,1)-system,we study Darboux transformations for space-like isothermic surfaces in Minkowski space R~(m,1),where G_(m,1)~(1,1)=O(m+1,2)/O(m,1)×O(1,1).
关键词 G_(m 1)~(1 1)-system Darboux transformation space-like isothermic surfaces
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A New Kind of Two-Fold Integration Transformation in Phase Space and Its Uses in Weyl Ordering of Operators 被引量:3
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作者 FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期935-937,共3页
We propose a new two-fold integration transformation in p-q phase space∫∫^∞-∞dpdq/π e^2i(p-x)(q-y)f(p,q)≡G(x,y),which possesses some well-behaved transformation properties. We apply this transformation t... We propose a new two-fold integration transformation in p-q phase space∫∫^∞-∞dpdq/π e^2i(p-x)(q-y)f(p,q)≡G(x,y),which possesses some well-behaved transformation properties. We apply this transformation to the Weyl ordering of operators, especially those Q-P ordered and P-Q ordered operators. 展开更多
关键词 new two-fold integration transform phase space Weyl ordering of operators
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Inverse log polar transformation algorithm based on sub-pixel interpolation 被引量:2
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作者 WANG Qi LI Yan-jun ZHANG Ke XIONG Xian-ze 《Optoelectronics Letters》 EI 2006年第3期213-216,共4页
Log polar transformation is an important algorithm of space-variant vision theory.It well depicts the retino-cortical mapping.Due to the logarithmic and the arctangent operation in the transformation,the log polar coo... Log polar transformation is an important algorithm of space-variant vision theory.It well depicts the retino-cortical mapping.Due to the logarithmic and the arctangent operation in the transformation,the log polar coordinate of an image is mostly a decimal fraction and the range is quite narrow.Aiming at solving these problems,this paper puts forward an inverse log polar transformation based on sub-pixel interpolation.The acquired log polar image of the new algorithm has no mosaic phenomenon,meanwhile it is a better simulation of retina-cortical mapping. 展开更多
关键词 化算法 空间变量 映射 插值
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Turbidity analysis using visible and near-infrared light images 被引量:2
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作者 ZHU Yuanyang ZHAO Wenzhu +1 位作者 LIU Sheng GAO Hongwen 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第1期27-35,共9页
The conventional photoelectric detection system requires complex circuitry and spectroscopic systems as well as specialized personnel for its operation.To replace such a system,a method of measuring turbidity using a ... The conventional photoelectric detection system requires complex circuitry and spectroscopic systems as well as specialized personnel for its operation.To replace such a system,a method of measuring turbidity using a camera is proposed by combining the imaging characteristics of a digital camera and the high-speed information processing capability of a computer.Two turbidity measurement devices based on visible and near-infrared(NIR)light cameras and a light source driving circuit with constant light intensity were designed.The RGB data in the turbidity images were acquired using a self-developed image processing software and converted to the CIE Lab color space.Based on the relationship between the luminance,chromatic aberration,and turbidity,the turbidity detection models for luminance and chromatic aberration of visible and NIR light devices exhibiting values from 0-1000 NTU,less than 100 NTU,and more than 100 NTU were established.By comparing and analyzing the proposed models,the two measurement models with the best all-around performance were selected and fused to generate new measurement models.The experimental results prove that the correlation between the three models and the commercial turbidity meter measurements exhibite a significance value higher than 0.999.The error of the fusion model is within 1.05%,with a mean square error of 1.14.The visible light device has less error at low turbidity measurements and is less influenced by the color of the image.The NIR light device is more stable and accurate at full range and high turbidity measurements and is therefore more suitable for such measurements. 展开更多
关键词 image processing water quality turbidity measurement near-infrared image color space conversion
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Spatial Relation Resolution and Spatial Relation Abstraction 被引量:2
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作者 AlTinghua LIUYaolin 《Geo-Spatial Information Science》 2003年第4期10-16,共7页
This paper attempts toregard spatial relation transformationas an important process in map gener-alization. The spatial relation generali-zation can be divided into the compo-nents of abstraction: topology, dis-tance ... This paper attempts toregard spatial relation transformationas an important process in map gener-alization. The spatial relation generali-zation can be divided into the compo-nents of abstraction: topology, dis-tance and orientation. The concept‘ spatial relation resolution' is intro-duced to describe the constraints ofrelative spatial relation. On the basisof nine intersection models, the cardi-nal direction models and the iso-dis-tance-relation models, this paper givesthree sorts of relation resolution repre-sentations for topological, distance andorientation relation, respectively. Twomapping implementations in map gen-eralization is discussed. 展开更多
关键词 map generalization spatial relation spatial relation resolu-tion
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Urban Spatial Restructuring in Transitional Economy——Changing Land Use Pattern in Shanghai 被引量:10
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作者 XU Jiangang LIAO Banggu +2 位作者 SHEN Qing ZHANG Feng MEI Anxin 《Chinese Geographical Science》 SCIE CSCD 2007年第1期19-27,共9页
For almost three decades, China has been undergoing significant transition from a planned economy to a market economy. Fast-paced economic growth and urbanization, interacting with market-oriented reforms in land re- ... For almost three decades, China has been undergoing significant transition from a planned economy to a market economy. Fast-paced economic growth and urbanization, interacting with market-oriented reforms in land re- sources allocation, have caused profound spatial restructuring of Chinese cities. This paper examines urban expansion and land use reconfiguration in Shanghai’s central city from 1979 to 2002, with a special focus on the effect of the adoption of the land-leasing system in 1988. The empirical research, which employs GIS-based spatial analysis tech- niques to explore land use data for multiple years, indicates fundamental changes in the spatial characteristics of urban development in Shanghai after this important land policy reform. 展开更多
关键词 land use pattern land policy GIS SHANGHAI China
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SPATIAL DIFFERENTIATION OF LAND TRANSFER——Case Study of Shanghai, Nanjing and Taizhou in Changjiang River Delta 被引量:5
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作者 DU Wen-xing HUANG Xian-jin +1 位作者 ZHAI Wen-xia PENG Bu-zhuo 《Chinese Geographical Science》 SCIE CSCD 2006年第1期24-31,共8页
The policy of land transfer has greatly influenced the macro economy of China with the commencement of another innovation of land use system. Therefore, it is urgent to put forward some rational and feasible suggestio... The policy of land transfer has greatly influenced the macro economy of China with the commencement of another innovation of land use system. Therefore, it is urgent to put forward some rational and feasible suggestions for local government to manage the market of land transfer. Moreover, it is important in the field of study on agricultural land use change to analyze the spatial differentiation and structural specification of land transfer, which are caused by rural households' behavior. This paper selected I l factors covering four aspects of rural households' family structure, family location, family income structure and the natural quality of land resources, all of which influence the behavior differentiation of rural households, to establish the index model indicating spatial differentiation of land transfer. Results show that the spatial differentiation of land transfer can be divided into four degrees and three categories through analyzing rural households' questionnaires from Shanghai, Nanjing and Taizhou in the Changjiang (Yangtze) River Delta. Since up to 80% of rural households belong to middle degrees, it can be concluded that the rural land market develops evenly in the study areas. And it is also indicated that the natural quality of land resources and the maximum income of rural land are most important factors influencing the spatial differentiation of land transaction. Considering different factors, the countermeasures can be carried out to enhance the spatial differentiation of land transfer so as to promote economic development and social security of rural China. All in all, both micro- factors and macro-factors influencing rural households' behavior of rural land transfer should be taken into account in order to make spatial differentiation and structural specification of rural land transfer notable. 展开更多
关键词 land transfer spatial differentiation land transaction Changjiang River Delta
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New Multi-soliton Solutions for the (2+1)-Dimensional Kadomtsev-Petviashvili Equation
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作者 Zhaqilao LI Zhi-Bin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期585-589,共5页
In this paper, an explicit N-fold Darboux transformation with multi-parameters for both a (1+1)- dimensional Broer-Kaup (BK) equation and a (1+1)-dimensional high-order Broer-Kaup equation is constructed with ... In this paper, an explicit N-fold Darboux transformation with multi-parameters for both a (1+1)- dimensional Broer-Kaup (BK) equation and a (1+1)-dimensional high-order Broer-Kaup equation is constructed with the help of a gauge transformation of their spectral problems. By using the Darboux transformation and new basic solutions of the spectral problems, 2N-soliton solutions of the BK equation, the high-order BK equation, and the Kadomtsev-Petviashvili (KP) equation are obtained. 展开更多
关键词 Darboux transformation soliton solution KP equation BK equation
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Reconstruction algorithm in lattice-invariant signal spaces
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作者 冼军 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期760-763,共4页
In this paper, we mainly pay attention to the weighted sampling and reconstruction algorithm in lattice-invariant signal spaces. We give the reconstruction formula in lattice-invariant signal spaces, which is a genera... In this paper, we mainly pay attention to the weighted sampling and reconstruction algorithm in lattice-invariant signal spaces. We give the reconstruction formula in lattice-invariant signal spaces, which is a generalization of former results in shift-invariant signal spaces. That is, we generalize and improve Aldroubi, Groechenig and Chen's results, respectively. So we obtain a general reconstruction algorithm in lattice-invariant signal spaces, which the signal spaces is sufficiently large to accommodate a large number of possible models. They are maybe useful for signal processing and communication theory. 展开更多
关键词 Lattice-invariant space Reconstruction algorithm Irregular sampling
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A Compact Low Energy Electron Microscope for Surface Analysis
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作者 张冠华 孙巨龙 +3 位作者 金艳玲 臧侃 郭方准 杨学明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第4期369-373,J0001,共6页
The description and function characterization of a flange-on type low energy electron mi- croscope are given. In this microscope a magnetic beam separator with 10° deflection angle is used in order to facilitate ... The description and function characterization of a flange-on type low energy electron mi- croscope are given. In this microscope a magnetic beam separator with 10° deflection angle is used in order to facilitate compacting the instrument on a single 10 in. flange. Mean- while some correcting elements in the electron optical system are simplified to reduce the complexities of construction and operation. The sample is set close to ground potential, so that all the electrostatic lenses are easily to float at high voltages. The performance of the microscope in typical low energy electron microscopy, low energy electron diffraction and photoemission electron microscopy modes is demonstrated through several experiments. A lateral resolution of 51 nm is estimated for low energy electron microscopy imaging. With femtosecond laser as light source, the consequent nonlinear photoemission makes this micro-scope also suitable for the observation of optical near field phenomena and a lateral resolution of 110 nm is obtained. 展开更多
关键词 Low energy electron microscopy Flange-on Femtosecond laser Lateral reso-lution Small deflection angle
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Notes on Application of WKB Method
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作者 GU Xiao-Yan SUN Jian-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期864-866,共3页
The notes here presented are of the modifications introduced in the application of WKB method.Theproblems of two-and three-dimensional harmonic oscillator potential are revisited by WKB and the new formulationof quant... The notes here presented are of the modifications introduced in the application of WKB method.Theproblems of two-and three-dimensional harmonic oscillator potential are revisited by WKB and the new formulationof quantization rule respectively.It is found that the energy spectrum of the radial harmonic oscillator,which isreproduced exactly by the standard WKB method with the Langer modification,is also reproduced exactly without theLanger modification via the new quantization rule approach.An alternative way to obtain the non-integral Maslov indexfor three-dimensional harmonic oscillator is proposed. 展开更多
关键词 WKB method quantization rules harmonic oscillator two-dimensional space
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Triaxial Shape, Signature Splitting, and Shape Coexistence in ^(127,129,131)Nd
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作者 DONG Bao-Guo MA Hai-Liang YAN Yu-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期187-192,共6页
Signature splitting and shape coexistence at high spin in the neutron deficient nucleus ^129Nd are investigated with the configuration-dependent cranked Nilsson-Strutinsky approach. The calculated bands are compared w... Signature splitting and shape coexistence at high spin in the neutron deficient nucleus ^129Nd are investigated with the configuration-dependent cranked Nilsson-Strutinsky approach. The calculated bands are compared with the observed signature partner bands and very good agreement results at high spin are obtained. The observed deformed bands are confirmed as normal and highly deformed and their properties are explained theoretically. Terminating states in ^129Nd and other terminations are predicted. There is shape coexistence within the same configuration from lowspin states to high-spin states. Possible normal and highly deformed bands with rotation around the intermediate principal axis in several interesting configurations of ^129Nd are discussed. The experimental results for ^131Nd are simply discussed and the calculated bands are in good agreement with observed bands at high spin. TriaxiM shapes in ^127 Nd with a triaxial deformation of γ -12° are predicted and should be observed experimentally. The value of negative γ of π(h11/2)^4v(h11/2)^7 configuration increases with neutron number increasing in ^127,129,131Nd. The triaxial shape evolutions with neutron number increasing in ^127,129,131Nd and in ^126,128,130,132pr are explained by the strong driving force of specified single particle orbitals towards to triaxial shape. 展开更多
关键词 rotational structure triaxial shape signature splitting CONFIGURATION
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Spectral Description of a Class of Infinite-Dimensional Hamiltonian Operators and Its Application to Plane Elasticity Equations Without Body Force
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作者 Alatancang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期983-986,共4页
In this paper,the results of spectral description and invertibility of upper triangle infinite-dimensionalHamiltonian operators with a diagonal domain are given.By the above results,it is proved that the infinite-dime... In this paper,the results of spectral description and invertibility of upper triangle infinite-dimensionalHamiltonian operators with a diagonal domain are given.By the above results,it is proved that the infinite-dimensionalHamiltonian operator associated with plane elasticity equations without the body force is invertible,and the spectrumof which is non-empty and is a subset of R. 展开更多
关键词 plane elasticity equations infinite-dimensional Hamiltonian operator SPECTRUM
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Urban China in Transformation:Hybrid Economy,Juxtaposed Space,and New Testing Ground for Geographical Enquiries 被引量:4
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作者 George C S LIN 《Chinese Geographical Science》 SCIE CSCD 2011年第1期1-16,共16页
History has brought us into a significant moment when the majority of the human kind has taken up resi-dence in urban settlements. The focus of global urbanization has shifted to the developing world and the center of... History has brought us into a significant moment when the majority of the human kind has taken up resi-dence in urban settlements. The focus of global urbanization has shifted to the developing world and the center of manufacturing is no longer confined to the Global North. This paper provides a periodical assessment of the current status of China's urban transformation in the global context of a shifting emphasis of industrialization and urbaniza-tion. China's phenomenal urban transformation deserves a special attention not only because of its unparalleled scale and speed but also because of its distinct trajectory of growth that does not conform to normal theoretical ex-pectations. The results of assessment revealed an urban economy with remarkable hybridity, a society that is in-creasingly stratified, polarized, and segregated, and a juxtaposed urban space undergoing restless and pervasive transformation. A decentering world should entail a decentering knowledge production. A critical reflection upon the Chinese patterns and processes of urban transformation has identified 4 main issues with great potentials for inno-vative knowledge production, namely: 1) privatization and economic development; 2) state, society, and space; 3) urbanization of capital, labor, and land; and 4) the environment and Chinese political ecology. The paper closes with the remark that a rapidly transforming urban China has presented itself as a fertile and resourceful testing ground for critical and innovative geographic enquiries. 展开更多
关键词 urban geography URBANIZATION Chinese cities political economy China
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Wireless Channel Parameter Estimation Algorithms: Recent Advances and Future Challenges 被引量:6
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作者 Rui Feng Yu Liu +3 位作者 Jie Huang Jian Sun Cheng-Xiang Wang George Goussetis 《China Communications》 SCIE CSCD 2018年第5期211-228,共18页
Temporal and three-dimensional(3 D) spatial information is important for the characterization of wireless channels. In this paper, the commonly used array signal processing(ASP) methods to estimate channel parameters ... Temporal and three-dimensional(3 D) spatial information is important for the characterization of wireless channels. In this paper, the commonly used array signal processing(ASP) methods to estimate channel parameters are summarized. Firstly, algorithms that can be used to estimate azimuth angle of arrival(AAo A) and elevation Ao A(EAo A) are introduced. They include multiple signal classification(MUSIC), estimation of signal parameter via rotational invariance techniques(ESPRIT), and Unitary ESPRIT algorithms. Secondly, algorithms that can be used to jointly estimate delay, AAo A, and EAo A are given. They include joint angle and delay estimation(JADE) MUSIC, JADE ESPRIT, shift-invariance(SI) JADE, and space-alternating generalized expectation-maximization(SAGE) algorithms. We also propose an improved SIJADE algorithm to further reduce computation complexity by incorporating with the Unitary ESPRIT algorithm. Performance of the above algorithms to extract only spatial information and to jointly extract temporal and spatial information is compared in both synthetic and 60 GHz real channel environments. Simulation results show that with the inclusion of delay estimation, the joint temporal and spatial estimation algorithms can provide better resolution than algorithms estimating only angles.Measurement data processing results show that MUSIC algorithm can provide comparable results with SAGE algorithm in estimating AAoA and EAoA. SI-JADE and the improved SI-JADE algorithms are also applicable to process 60 GHz channel measurement data.However, MUSIC, SI-JADE, and the improved SI-JADE algorithms can greatly reduce computational burden compared with SAGE algorithm. At last, some future directions are pointed out. 展开更多
关键词 MUSIC JADE MUSIC/ESPRIT SI-JADE SAGE algorithm millimeter wave
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