نظریه دما و نویز و کاربردهای آن در سیستم‌های آنتن‌ ارتباطات فضایی عمیق (کتابخانه آنتن‌ها و انتشار آرتک هاوس)

deep Space Communications Technology Is Bringing Home Benefits To All Types Of Microwave Communications Systems. This Groundbreaking Resource Explains The Breakthroughs That The Nasa Jpl Deep Space Antenna Network Achieved In Reducing Noise And Signal Interference. The Book Focuses On Ground-based Receivers And How They Can Be Improved To Pick Up Weak Or Disrupted Signals. Practicing Microwave Engineers In All Fields Can Apply These Theories And Methods To Improve Systems Performance. In Particular, Engineers Working On Deep-space Antenna Systems Can Make The Most Of The Techniques For Analyzing Errors Caused By Noise Temperature. The Book Explains How To Confidently Predict Receiver Noise Temperature Thereby Boosting The Capability To Receive Data. Tutorials, Practical Formulas, And Powerful Techniques Earn This Book A Permanent Place On Every Microwave And Antenna Engineer's Desk. Noise Temperature Theory and Applications for Deep Space Communications Antenna Systems......Page 2 Contents vii......Page 8 Foreword xi......Page 12 Preface xiii......Page 14 Acknowledgments xv......Page 16 1.1 Antenna Noise Temperature as Functions of Pointing Angles 1......Page 18 1.2 Cosmic Background Noise Temperature 37......Page 54 1.3 Portable Microwave Test Packages 40......Page 57 1.4 Dichroic Plate in a Beam-Waveguide Antenna System 50......Page 67 2.1 Perforated Panels 71......Page 88 2.2 Solid Panels 88......Page 105 2.3 Painted Panels 108......Page 125 2.4 Wet Panels 131......Page 148 Noise Temperature Experiments 137......Page 154 3.2 Bird Net Cover for BWG Antennas 152......Page 169 3.3 G/T Improvement Task 156......Page 173 3.4 Measured Sun Noise Temperature at 32 GHz 172......Page 189 4.1 Antenna System Noise Temperature Calibration Mismatch Errors 189......Page 206 4.2 Equivalent Source Noise Temperature at Output of Cascaded Lossy Networks 222......Page 239 4.3 Effective Input Noise Temperature at Input of Cascaded Lossy Networks 229......Page 246 5.1 Two-Port Network Containing Two Internal Paths 235......Page 252 5.2 Three-Port Network with Two External Noise Sources 252......Page 269 6.1 Formulas Associated with Solid Metal Reflectors 269......Page 286 6.2 Formulas Associated with Metal Reflectors with Holes 271......Page 288 6.3 Other Useful Formulas 276......Page 293 About the Author 281......Page 298 Index 283......Page 300 "Confidently predict receiver system noise temperature using the techniques developed for NASA-JPL's Deep Space Network techniques presented, for the first time, in this groundbreaking resource. The book shows you how to analyze, design, measure and accurately evaluate the many detailed elements comprising noise temperature. After a thorough introductory overview, you delve into reflector performance issues, including material conductivity, perforations, protective coatings, the effects of terrestrial weather, and the influence of the Earth's Sun. This in-depth reference covers mismatch error equations, in terms of both reflection coefficient magnitudes and VSWRs. Moreover, you find expert guidance in calibrating system noise temperature and antenna efficiency. The book includes easy-to-use formulas that enable you to calculate noise temperature of solid metallic reflector surfaces and of leaks in perforated plates or wire grids. What's more, you get an invaluable tutorial on using S- parameters to predict noise temperature of multiports."--Publisher Explains the breakthroughs that the NASA JPL Deep Space Antenna Network achieved in reducing noise and signal interference. This book focuses on ground-based receivers and how they can be improved to pick up weak or disrupted signals. It explains how to confidently predict receiver noise temperature thereby boosting the capability to receive data