AP公司的Loudspeaker EA Measurements-扬声器电声测量
2024-03-26 07:33:57 1.94MB
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LTE RF Measurements with the R&S®CMW500 according to 3GPP TS 36.521-1
2023-02-07 11:23:00 3.69MB LTE CMW500
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Basic Performance Measurements of the Intel Optane DC Persistent
2022-10-06 14:00:30 1.28MB NVDIMM
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双频降水雷达Python软件包(DRpy) (发音为derpy) 注意:修复了io功能(2021年3月8日) 我期待使用自定义绘图功能。 在本月晚些时候给大家。 drpy.core.GPMDPR(): 此类旨在从NASA的全球降水测量任务双频降水雷达(GPM-DPR)中读取hdf5文件到xarray数据集中。 drpy.core.APR(): 此类旨在用于从NASA的机载降水雷达(主要在OLYMPEX中开发)中读取hdf5文件,因此,如果您使用其他活动时要当心,则某些数据集名称可能会有所不同。 创建此程序包的原因不是重新发明轮子(即h5py可以正常工作),而是允许用户访问xarray中的有用功能。 具体来说,当前支持的数据文件是2级DPR文件(2A.DPR *)。 拥有帐户后,您可以从这里免费下载它们:ftp://arthurhou.pps.eosdis.nasa.gov
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Image Correlation for Shape, Motion and Deformation Measurements
2022-05-16 09:14:34 10.05MB 机器人
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这项研究报告了在11 GHz和14 GHz的室内传播测量活动和信道表征的结果,它们是未来通信系统的候选频段。 测量程序可以表征视距(LOS)和非LOS(NLOS)通道的大型和小型统计数据。 基于这些测量,提出了对数距离路径损耗模型,并讨论了均方根(RMS)延迟扩展。 通过使用Kolmogorov-Smirnov,卡方检验和Anderson-Darling检验,发现Nakagami分布很好地描述了小规模衰落的统计数据。 提出了一种与距离有关的线性模型来预测Nakagami m参数。 此外,根据测量结果分析了这些信道参数的互相关性,并且在LOS条件下可以清楚地观察到阴影衰落,RMS延迟扩展和m因子之间的互相关性,而NLOS的阻塞减少了互相关性。相关性。
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Principles of Planar Near-Field Antenna Measurements 介绍天线近场测量的基础知识 Contents Preface xi 1 Introduction 1 1.1 The phenomena of antenna coupling 1 1.2 Characterisation via the measurement process 4 1.2.1 Free space radiation pattern 6 1.2.2 Polarisation 7 1.2.3 Bandwidth 8 1.3 The organisation of the book 11 1.4 References 12 2 Maxwell’s equations and electromagnetic wave propagation 13 2.1 Electric charge 13 2.2 The EM field 14 2.3 Accelerated charges 16 2.4 Maxwell’s equations 18 2.5 The electric and magnetic potentials 24 2.5.1 Static potentials 24 2.5.2 Retarded potentials 24 2.6 The inapplicability of source excitation as a measurement methodology 28 2.7 Field equivalence principle 28 2.8 Characterising vector EM fields 30 2.9 Summary 33 2.10 References 33 3 Introduction to near-field antenna measurements 35 3.1 Introduction 35 3.2 Antenna measurements 35 3.3 Forms of near-field antenna measurements 40 3.4 Plane rectilinear near-field antenna measurements 43 3.5 Chambers, screening and absorber 44 3.6 RF subsystem 47 3.7 Robotics positioner subsystem 52 3.8 Near-field probe 56 3.9 Generic antenna measurement process 58 3.10 Summary 60 3.11 References 60 4 Plane wave spectrum representation of electromagnetic waves 63 4.1 Introduction 63 4.2 Overview of the derivation of the PWS 64 4.3 Solution of the scalar Helmholtz equation in Cartesian coordinates 65 4.3.1 Introduction to integral transforms 65 4.3.2 Fourier transform solution of the scalar Helmholtz equation 65 4.4 On the choice of boundary conditions 78 4.5 Operator substitution (derivative of a Fourier transform) 79 4.6 Solution of the vector Helmholtz equation in Cartesian coordinates 81 4.7 Solution of the vector magnetic wave equation in Cartesian coordinates 83 4.8 The relationship between electric and magnetic spectral components 84 4.9 The free-space propagation vector k 87 4.10 Plane wave impedance 88 4.11 Interpretation as an angular spectrum of plane waves 90 4.12 Far-field antenna radiation patterns: approximated by the angular spectrum 92 4.13 Stationary phase evaluation of a double integral 95 4.14 Coordinate free form of the near-field to angular spectrum transform 101 4.15 Reduction of the coordinate free form of the near-field to far-field transform to Huygens’ principle 104 4.16 Far-fields from non-planar apertures 106 4.17 Microwave holographic metrology (plane-to-plane transform) 107 4.18 Far-field to near-field transform 108 4.19 Radiated power and the angular spectrum 112 4.20 Summary of conventional near-field to far-field transform 115 4.21 References 117 5 Measurements – practicalities of planar near-field antenna measurements 119 5.1 Introduction 119 5.2 Sampling (interpolation theory) 120 5.3 Truncation, spectral leakage and finite area scan errors 121 5.4 Antenna-to-antenna coupling (transmission) formula 125 5.4.1 Attenuation of evanescent plane wave mode coefficients 136 5.4.2 Simple scattering model of a near-field probe during a planar measurement 137 5.5 Evaluation of the conventional near-field to far-field transform 138 5.5.1 Standard techniques for the evaluation of a double Fourier integral 139 5.6 General antenna coupling formula: arbitrarily orientated antennas 143 5.7 Plane-polar and plane-bipolar near-field to far-field transform 148 5.7.1 Boundary values known in plane-polar coordinates 150 5.7.2 Boundary values known in plane-bipolar coordinates 151 5.8 Regular azimuth over elevation and elevation over azimuth coordinate systems 156 5.9 Polarisation basis and antenna measurements 159 5.9.1 Cartesian polarisation basis – Ludwig I 159 5.9.2 Polar spherical polarisation basis 160 5.9.3 Azimuth over elevation basis – Ludwig II 161 5.9.4 Copolar and cross-polar polarisation basis – Ludwig III 163 5.9.5 Circular polarisation basis – RHCP and LHCP 165 5.10 Overview of antenna alignment corrections 169 5.10.1 Scalar rotation of far-field antenna patterns 169 5.10.2 Vector rotation of far-field antenna patterns 171 5.10.4 Rotation of copolar polarisation basis – generalized Ludwig III 173 5.10.5 Generalized compound vector rotation of far-field antenna patterns 174 5.11 Brief description of near-field coordinate systems 175 5.11.1 Range fixed system 176 5.11.2 Antenna mechanical system 177 5.11.3 Antenna electrical system 178 5.11.4 Far-field azimuth and elevation coordinates 178 5.11.5 Ludwig III copolar and cross-polar definition 178 5.11.6 Probe alignment definition (SPP) 178 5.11.7 General vector rotation of antenna radiation patterns 179 5.12 Directivity and gain 180 5.12.1 Directivity 180 5.12.2 Gain – by substitution method 181 5.12.3 Gain-transfer (gain-comparison) method 182 5.13 Calculating the peak of a pattern 183 5.13.1 Peak by polynomial fit 183 5.13.2 Peak by centroid 185 5.14 Summary 186 5.15 References 187 6Pr obe pattern characterisation 189 6.1 Introduction 189 6.2 Effect of the probe pattern on far-field data 189 6.3 Desirable characteristics of a near-field probe 191 6.4 Acquisition of quasi far-field probe pattern 193 6.4.1 Sampling scheme 194 6.4.2 Electronic system drift (tie-scan correction) 197 6.4.3 Channel-balance correction 198 6.4.4 Assessment of chamber multiple reflections 200 6.4.5 Correction for rotary errors 202 6.4.6 Re-tabulation of probe vector pattern function 205 6.4.7 Alternate interpolation formula 209 6.4.8 True far-field probe pattern 211 6.5 Finite element model of open-ended rectangular waveguide probe 213 6.6 Probe displacement correction 217 6.7 Channel-balance correction 217 6.8 References 218 7 Computational electromagnetic model of a planar near-field measurement process 219 7.1 Introduction 219 7.2 Method of sub-apertures 220 7.3 Aperture set in an infinite perfectly conducting ground plane 223 7.3.1 Plane wave spectrum antenna–antenna coupling formula 225 7.4 Vector Huygens’ method 227 7.5 Kirchhoff–Huygens’ method 229 7.6 Generalized technique for the simulation of near-field antenna measurements 233 7.6.1 Mutual coupling and the reaction theorem 234 7.7 Near-field measurement simulation 237 7.8 Reaction theorem 239 7.8.1 Lorentz reciprocity theorem (field reciprocity theorem) 240 7.8.2 Generalized reaction theorem 244 7.8.3 Mutual impedance and the reaction theorem 247 7.9 Summary 247 7.10 References 248 8 Antenna measurement analysis and assessment 249 8.1 Introduction 249 8.2 The establishment of the measure from the measurement results 249 8.2.1 Measurement errors 250 8.2.2 The sources of measurement ambiguity and error 253 8.2.3 The examination of measurement result data to establish the measure 256 8.3 Measurement error budgets 259 8.3.1 Applicability of modelling error sources 259 8.3.2 The empirical approach to error budgets 260 8.4 Quantitative measures of correspondence between data sets 261 8.4.1 The requirement for measures of correspondence 261 8.5 Comparison techniques 263 8.5.1 Examples of conventional data set comparison techniques 263 8.5.2 Novel data comparison techniques 267 8.6 Summary 282 8.7 References 283 9 Advanced planar near-field antenna measurements 285 9.1 Introduction 285 9.2 Active alignment correction 285 9.2.1 Acquisition of alignment data in a planar near-field facility 287 9.2.2 Acquisition of mechanical alignment data in a planar near-field facility 289 9.2.3 Example of the application of active alignment correction 291 9.3 Amplitude only planar near-field measurements 296 9.3.1 PTP phase retrieval algorithm 297 9.3.2 PTP phase retrieval algorithm – with aperture constraint 301 9.4 Efficient position correction algorithms, in-plane and z−plane corrections 303 9.4.1 Taylor series expansion 305 9.4.2 K-correction method 311 9.5 Partial scan techniques 315 9.5.1 Auxiliary translation 315 9.5.2 Rotations of the AUT about the z-axis 319 9.5.3 Auxiliary rotation – bi-planar near-field antenna measurements 320 9.5.4 Near-field to far-field transformation of probe corrected data 329 9.5.5 Applicability of the poly-planar technique 335 9.5.6 Complete poly-planar rotational technique 338 9.6 Concluding remarks 342 9.7 References 344 Appendix A: Other theories of interaction 347 A.1 Examples of postulated mechanisms of interaction 347 Appendix B: Measurement definitions as used in the text 354 Appendix C: An overview of coordinate systems 357 C.1 Antenna mechanical system (AMS) 357 C.2 Antenna electrical system (AES) 357 C.3 Far-field plotting systems 358 C.4 Direction cosine 358 C.5 Azimuth over elevation 360 C.6 Elevation over azimuth 361 C.7 Polar spherical 362 C.8 Azimuth and elevation (true-view) 364 C.9 Range of spherical angles 365 C.10 Transformation between coordinate systems 366 C.11 Coordinate systems and elemental solid angles 367 C.12 Relationship between coordinate systems 368 C.13 Azimuth, elevation and Roll angles 371 C.14 Euler angles 373 C.15 Quaternion 374 C.16 Elemental solid angle for a true-view coordinate system 377 Appendix D: Trapezoidal discrete Fourier transform 380 Appendix E: Calculating the semi-major axis, semi-minor axis and tilt angle of a rotated ellipse 384 Index 389
2022-03-25 05:09:19 5.22MB Antenna Near-Field Measurement
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matlab雷达距离距离代码卡尔曼滤波器融合雷达传感器 3D 测量 使用非线性卡尔曼滤波器进行目标跟踪(单传感器、单目标)的状态估计 这是 matlab 中的扩展卡尔曼滤波器实现,用于在 3D 中融合雷达传感器测量。 传感器测量的三维目标包括距离(距离) r 、方位角(转弯角)θ和仰角(仰角)\Phi。 Range r表示测得的目标距跟踪器中心的距离,而方位角或旋转角 \Theta 表示跟踪器在 x 轴和 y 轴方向旋转的运动方向,仰角 \Phi 表示跟踪器仰角在x、y到z轴方向的运动方向。 此文件尚未完成。 等式、代码说明和图片将很快上传。
2021-11-28 10:57:28 17KB 系统开源
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GPS经典文章,由Stanford的P.Misra编写
2021-09-23 15:31:28 1.75MB GPS
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《雷达散射截面测量》 Eugene F. Knott 的英文原版,详细介绍了雷达散射截面(RCS)的测量。
2021-08-19 11:37:53 14.31MB 雷达散射截面 Radar radar cross
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