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Interferometry and Synthesis in Radio Astronomy:

Interferometry and Synthesis in Radio Astronomy
By A. Richard Thompson, James M. Moran, George W., Jr. Swenson

Publisher: Wiley-Interscience
Number Of Pages: 715
Publication Date: 2001-05-02
ISBN-10 / ASIN: 0471254924
ISBN-13 / EAN: 9780471254928
Binding: Hardcover

Comprehensive, authoritative coverage of interferometric techniques for radio astronomy

In this Second Edition of Interferometry and Synthesis in Radio Astronomy, three leading figures in the development of large imaging arrays, including very-long-baseline interferometry (VLBI), describe and explain the technology that provides images of the universe with an angular resolution as fine as 1/20,000 of an arcsecond.

This comprehensive volume begins with a historical review followed by detailed coverage of the theory of interferometry and synthesis imaging, analysis of interferometer response, geometrical relationships, polarimetry, antennas, and arrays. Discussion of the receiving system continues with analysis of the response to signals and noise, analog design requirements, and digital signal processing.

The authors detail special requirements of VLBI including atomic frequency standards, broadband recording systems, and antennas in orbit. Further major topics include:
* Calibration of data and synthesis of images
* Image enhancement using nonlinear algorithms
* Techniques for astrometry and geodesy
* Propagation in the neutral atmosphere and ionized media
* Radio interference
* Related techniques: intensity interferometry, moon occultations, antenna holography, and optical interferometry

Interferometry and Synthesis in Radio Astronomy, Second Edition is comprehensive in that it provides an excellent overview of most radio astronomical instrumentation and techniques.

Summary: amazing engineering feats
Rating: 4

You can think of this as a course in very specialised antenna design. Certainly, the broad concepts would be immediately recognisable to any engineer who has built antennas. But here the sources that are being detected are at far reaches indeed. Correspondingly, the sizes of each radio dish far exceeds your typical antenna in industrial or military use.

Of course, the book points out that radio telescopes further enhance their resolving power by positioning these dishes at precise distances from each other, and adjusting the phases of incoming signals accordingly. To someone new to radio astronomy, one of the impressive achievements is that an array of dishes can thus be combined into one large telescope, spanning several kilometers.

The book then shows how this is taken to a logical limit of VLBI. Where arrays at different locations across the globe might combine their signals, giving a telescope comparable to the size of the globe, for greater resolution. A tribute to how engineering helps drive advances in pure research.

巧遇啊，对这些内容正在好奇，占位等书……

It is new book,just wait for download

:31bb :31bb :31bb

CONTENT'S
Preface to the Second Edition
Preface to the First Edition
1 Introduction and Historical Review
1.1 Applications of Radio Interferometry 1
1.2 Basic Tenns and Definitions 3
Cosmic Signals 3
Source Positions and Nomenclature 9
Receptiorl of Cosmic Signals 10
Evolution of Synthesis Techniques 12
Michelson Interferometer 13
Early 'ho-Element Radio Interferometers 16
Sea Interferometer 18
Phase-Switching Interferometer 18
Optical Identifications and Calibration Sources 21
Early Me,isurements of Angular Width 21
Survey Interferometers and the Mills Cross
Centimetcr-Wavelength Solar Mapping 26
Measurements of Intensity Profiles 27
Spectral Line Interferometry 28
Earth-Rolation Synthesis Mapping 28
Developnient of Synthesis Arrays 3 1
Very-Long-Baseline Interferometry 33
VLBI Us; ng Orbiting Antennas 37
1.3 Development of Radio Interferometry 12
24
1.4 Quantum Effect 39
xix
XXi
1
2 Introductory Thcory of Interferometry and Synthesis Imaging 50
2.1 Planar Analysis 50
2.2 Effect of Bandwidth 53
ix
x CONTENTS
2.3 One-Dimensional Source Synthesis 57
Interferometer Response as a Convolution 58
Convolution Theorem and Spatial Frequency 60
Example of One-Dimensional Synthesis 61
Projection-Slice Theorem 65
2.4 Two-Dimensional Synthesis 64
3 Analysis of the Interferometer Response 68
3.1 Fourier Transform Relationship between Intensity and
Visibility 68
3.2 Cross-Correlation and the Wiener-Khinchin Relation 77
3.3 Basic Response of the Receiving System 78
Antennas 78
Filters 79
Correlator 80
Response to the Incident Radiation 80
Analytic Signal 82
Truncated Function 84
Appendix 3.1 Mathematical Representation of Noise-Like Signals 82
4 Geometric Relationships and Polarimetry
4.1 Antenna Spacing Coordinates and ( u , u ) Loci 86
4.2 (u’, u’) Plane 90
4.3 Fringe Frequency 91
4.4 Visibility Frequencies 92
4.5 Calibration of the Baseline 93
4.6 Antenna Mounts 94
4.7 Beamwidth and Beam-Shape Effects 96
4.8 Polarimetry 97
Parameters Defining Polarization 97
Antenna Polarization Ellipse 99
Stokes Visibilities 102
Instrumental Polarization 105
Matrix Formulation 109
Calibration of Instrumental Polarization
Appendix 4.1 Conversion Between Hour Angle-Declination and
Azimuth-Elevation Coordinates 1 17
Appendix 4.2 Leakage Parameters in Terms of the Polarization Ellipse
Linear Polarization 1 18
Circular Polarization 119
1 12
117
86
5 Antennas and Arrays
CONTENTS xi
122
5. I
5.2
5.3
5.4
5.5
5.6
5.7
5.8
Antennas 122
Sampling 1 he Visibility Function
Sampling 'heorem 126
Discrete TNo-Dimensional Fourier Transform
Introductory Discussion of Arrays 129
Phased Arrays and Correlator Arrays
Spatial Sensitivity and the Spatial Transfer Function
Meter-Wavelength Cross and T Arrays
Spatial Transfer Function of a Tracking Array 138
Desirable Characteristics of the Spatial Transfer Function
Holes in the Spatial Frequency Coverage
Linear Tracking Arrays 142
Two-Dime nsional Tracking Arrays 147
Open-Endzd Configurations 148
Closed Configurations 150
VLBI Configurations I55
Orbiting C'LBI Antennas 158
Planar Arrays 159
Conclusions on Antenna Configurations 161
Other Considerations 162
Sensitivit) 162
Long Wavelengths 163
Millimeter Wavelengths 163
126
1 28
129
132
137
140
14 1
6 Response of the Receiving System 168
Frequency Conversion, Fringe Rotation, and Complex
Correlators 168
Frequencj Conversion 168
Response of a Single-Sideband System
Upper-Sideband Reception 17 I
Lower-Sideband Reception 172
Multiple Frequency Conversions 173
Delay Trazking and Fringe Rotation
Simple and Complex Correlators 174
Response of a Double-Sideband System
Double-Sideband System with Multiple Frequency
Fringe Stopping in a Double-Sideband System 180
Relative Advantages of Double- and Single-Sideband
6.1
169
173
175
Conversions 178
Systems 181
i i CONTENTS
Sideband Separation 18 I
Signal and Noise Processing in the Correlator
Noise in the Measurement of Complex Visibility
Signal-to-Noise Ratio in a Synthesized Map
Noise in Visibility Amplitude and Phase
Relative Sensitivities of Different Interferometer Systems
System Temperature Parameter a 199
Mapping in the Continuum Mode 200
Wide-Field Mapping with a Multichannel System
6.4 Effect of Visibility Averaging 205
Visibility Averaging Time 205
Effect of Time Averaging 206
6.2 Response to the Noise 183
183
188
189
192
193
6.3 Effect of Bandwidth 199
204
Appendix 6.1 Partial Rejection of a Sideband 208
7 Design of the Analog Receiving System 212
7. I Principal Subsystems of the Receiving Electronics 212
Low-Noise Input Stages 2 12
Noise Temperature Measurement 2 14
Local Oscillator 2 17
IF and Signal Transmission Subsystems 21 8
Optical Fiber Transmission 21 8
Delay and Correlator Subsystems 220
7.2 Local Oscillator and General Considerations of Phase
Stability 22 I
Round-Trip Phase Measuring Schemes 22 1
Swarup and Yang System 222
Frequency-Offset Round-Trip System 223
Automatically Correcting System 228
Fiberoptic Transmission of LO Signals 229
Phase-Locked Loops and Reference Frequencies 230
Phase Stability of Filters 232
Effect of Phase Errors 233
7.3 Frequency Responses of the Signal Channels 233
Optimum Response 233
Tolerances on Variation of the Frequency Response:
Tolerances on Variation of the Frequency Response:
Degradation of Sensitivity 235
Gain Errors 235
CONTENTS xiii
7.4
7.5
7.6
Appendix 7.1
Appendix 7.2
Delay-Set1 ing Tolerances 238
1mplemen:ation of Bandpass Tolerances 239
Polarization Mismatch Errors 240
Phase Switching 240
Reduction of Response to Spurious Signals 240
Implementation of Phase Switching 241
Interaction of Phase Switching with Fringe Rotation and Delay
Automatic Level Control and Gain Calibration
Sideband-Separating Mixer 248
Dispersioii in Optical Fiber 249
Adjustment 246
248
8 Digital Signal Pralcessing
8.1
8.2
8.3
8.4
8.5
8.6
8.7
Appendix 8.1
Appendix 8.2
Bivariate Gaussian Probability Distribution 255
Periodic Sampling 256
Nyquist Rate 256
Correlation of Sampled but Unquantized Waveforms 257
Sampling with Quantization 260
Two-Level Quantization 261
Four-Level Quantization 264
Three-Level Quantization 27 I
Quantizat on with Eight or More Levels
Quantization Correction 276
Comparison of Quantization Schemes 277
System Sensitivity 278
Accuracy in Digital Sampling 278
Principal Causes of Error 278
Tolerances in Three-Level Sampling 279
Digital Delay Circuits 282
Quadrature Phase Shift of a Digital Signal 283
Digital Correlators 283
Correlators for Continuum Observations 283
Principles of Digital Spectral Measurements
Lag (XF) Correlator 289
FX Correi ator 290
Comparison of Lag and FX Correlators
Hybrid Correlator 297
Demultipi exing in Broadband Correlators 297
Evaluatioi of c,"=R&,( qr,) 298
Probability Integral for Two-Level Quantization 299
273
284
293
254
xiv CONTENTS
Appendix 8.3 Correction for Four-Level Quantization 300
9 Very-Long-Baseline Interferometry
9.1
9.2
9.3
9.4
9.5
9.6
9.7
9.8
9.9
9.10
Early Development 304
Differences Between VLBI and Conventional
Interferometry 306
Basic Performance of a VLBI System 308
Time and Frequency Errors 308
Retarded Baselines 3 15
Noise in VLBI Observations
Probability of Error in the Signal Search 319
Coherent and Incoherent Averaging 323
Fringe Fitting for a Multielement Array
Global Fringe Fitting 326
Relative Performance of Fringe Detection Methods 329
Triple Product, or Bispectrum 330
Fringe Searching with a Multielement Array 331
Multielement Array with Incoherent Averaging 33 1
Phase Stability and Atomic Frequency Standards 332
Analysis of Phase Fluctuations 332
Oscillator Coherence Time 340
Precise Frequency Standards 342
Rubidium and Cesium Standards 346
Hydrogen Maser Frequency Standard 348
Local Oscillator Stability 35 1
Phase Calibration System 352
Time Synchronization 353
Recording Systems 353
Processing Systems and Algorithms 357
Fringe Rotation Loss ( q ~ )35 8
Fringe Sideband Rejection Loss ( q s ) 36 1
Discrete Delay Step Loss ( q D ) 363
Summary of Processing Losses 365
Bandwidth Synthesis 366
Burst Mode Observing 368
Phased arrays as VLBI Elements 369
Orbiting VLBI (OVLBI) 373
3 16
326
304
CONTENTS xv
10 Calibration and Fourier Transformation of Visibility Data 383
10.1
10.2
10.3
10.4
10.5
10.6
Appendix 10.1
Appendix 10.2
Appendix 10.3
Calibration of the Visibility 383
Corrections for Calculable or Directly Monitored Effects
Use of Calibration Sources 385
Derivation of Intensity from Visibility
Mapping tiy Direct Fourier Transformation
Weighting of the Visibility Data 388
Mapping tly Discrete Fourier Transformation
Convolving Functions and Aliasing 394
Aliasing and the Signal-to-Noise Ratio 398
Closure Relationships 399
Model Fitling 401
Basic Considerations for Models 402
Cosmic Biickground Anisotropy 404
Spectral Line Observations 404
General Considerations 404
VLBI Observations of Spectral Lines 406
Variation of Spatial Frequency over the Bandwidth 409
Accuracy of Spectral Line Measurements 409
Presentation and Analysis of Spectral Line Observations
Miscel1anc:ous Considerations 4 1 1
Interpretation of Measured Intensity 41 1
Errors in Maps 41 2
Hints on Planning and Reduction of Observations 413
The Edge of the Moon as a Calibration Source 414
Doppler Shift of Spectral Lines 417
Historical Notes 42 1
Maps from One-Dimensional Profiles 421
Analog Fourier Transformation 422
384
387
387
392
4 10
1 1 Deconvolution, Aldaptive Calibration, and Applications
1 1.1 Limitation of Spatial Frequency Coverage 426
1 1.2 The Clean Deconvolution Algorithm 427
CLEAN Algorithm 427
Implementation and Performance of the CLEAN
Algorithm 429
MEM Algorithm 432
Comparison of CLEAN and MEM 434
Other Dec,onvolution Procedures 435
1 1.3 Maximum Entropy Method 432
426
11.4
11.5
11.6
11.7
11.8
11.9
Adaptive Calibration and Mapping With Amplitude Data
Only 438
Hybrid Mapping 438
Self-Calibration 440
Mapping with Visibility Amplitude Data Only 444
Mapping With High Dynamic Range 445
Mosaicking 446
Methods of Producing the Mosaic Map 449
Some Requirements of Arrays for Mosaicking 45 1
Multifrequency Synthesis 453
Non-Coplanar Baselines 454
Further Special Cases of Image Analysis 459
Use of CLEAN and Self-Calibration with Spectral
Low-Frequency Mapping 459
Lensclean 461
Line Data 459
12 Interferometer Techniques for Astrometry and Geodesy
12.1
12.2
12.3
12.4
12.5
Appendix 12.1
Requirements for Astrometry 467
Reference Frames 469
Solution for Baseline and Source-Position Vectors 470
Connected-Element Systems 470
Measurements with VLBI Systems 472
Phase Referencing in VLBI 476
Time and the Motion of the Earth 480
Precession and Nutation 48 1
Polar Motion 482
Universal Time 482
Measurement of Polar Motion and UTl
Geodetic Measurements 485
Mapping Astronomical Masers 485
Least-Mean-Squares Analysis 490
484
13 Propagation Effects
13.1 Neutral Atmosphere 508
Basic Physics 508
Refraction and Propagation Delay 5 13
Absorption 5 18
Origin of Refraction 524
Smith-Weintraub Equation 528
Phase Fluctuations 530
467
507
CONTENTS xvii
13.2
13.3
13.4
13.5
13.6
Kolmogorov Turbulence 534
Anomalous Refraction 539
Water Vapx Radiometry 54 I
Atmospheric Effects at Millimeter Wavelengths 543
Site Testing by Opacity Measurement
Site Testing by Direct Measurement of Phase Stability
Reduction of Atmospheric Phase Errors by Calibration
Ionosphert: 554
Basic Physics 555
Refraction and Propagation Delay 559
Calibration of Ionospheric Delay 560
Absorption 562
Small- and Large-Scale Irregularities 562
Scattering Caused by Plasma Irregularities 564
Gaussian !Screen Model 564
Power-Law Model 569
Interplanetary Medium 57 1
Refraction 57 1
Interplanetary Scintillation 574
Interstellar Medium 576
Dispersion and Faraday Rotation 576
Diffractivt: Scattering 579
Refractive Scattering 580
543
546
550
14 Van Cittert-Zernike Theorem, Spatial Coherence, and Scattering 594
14.1
14.2
14.3
Van Cittert-Zernike Theorem 594
Mutual Coherence of an Incoherent Source 596
Diffraction at an Aperture and the Response of an Antenna 597
Assumptions in the Derivation and Application of the Van
Spatial Coherence 602
Incident F'ield 602
Source Coherence 603
Completely Coherent Source 606
Scattering and the Propagation of Coherence
Cittert-Zernike Theorem 600
607
15 Radio Interference
15.1 General Considerations 6 13
15.2 Short- anti Intermediate-Baseline Arrays 61 5
Fringe-Fr'zquency Averaging 6 16
613
Decorrelation of Broadband Signals 620
15.3 Very-Long-Baseline Systems 621
15.4 Interference From Airborne and Space Transmitters 624
Appendix 15.1 Regulation of the Radio Spectrum 625
16 Related Techniques 627
16.1 Intensity Interferometer 627
16.2 Lunar Occultation Observations 632
16.3 Measurements on Antennas 636
16.4 Optical Interferometry 641
Modem Michelson Interferometer 642
Sensitivity of Direct Detection and Heterodyne Systems 644
Optical Intensity Interferometer 646
Speckle Imaging 647
Principal Symbols 655
Author Index 667
Subject Index 677

Interferometry and Synthesis in Radio Astronomy.part1