Microwave Propagation and Remote Sensing Atmospheric Influences with Models and Applications

Because prevailing atmospheric/troposcopic conditions greatly influence radio wave propagation above 10 GHz, the unguided propagation of microwaves in the neutral atmosphere can directly impact many vital applications in science and engineering. These include transmission of intelligence, and radar and radiometric applications used to probe the atmosphere, among others. Where most books address either one or the other, Microwave Propagation and Remote Sensing: Atmospheric Influences with Models and Applications melds coverage of these two subjects to help readers develop solutions to the problems they present. This reference offers a brief, elementary account of microwave propagation through the atmosphere and discusses radiometric applications in the microwave band used to characterize and model atmospheric constituents, which is also known as remote sensing. Summarizing the latest research results in the field, as well as radiometric models and measurement methods, this book covers topics including: Free space propagation Reflection, interference, polarization, and other key aspects of electromagnetic wave propagation Radio refraction and its effects on propagation delay Methodology of estimating water vapor attenuation using radiosonde data Knowledge of rain structures and use of climatological patterns to estimate/measure attenuation of rain, snow, fog, and other prevalent atmospheric particles and human-made substances Dual/multifrequency methodology to deal with the influence of clouds on radiometric attenuation Deployment of microwaves to ascertain various tropospheric conditions Composition and characteristics of the troposphere, to help readers fully understand microwave propagation Derived parameters of water, free space propagation, and conditions and variable constituents such as water vapor and vapor pressure, density, and ray bending

Outlines of Radio Waves and TroposphereGeneral PerspectiveTroposphereThe Effective Earth’s RadiusRadio LinkClassification of Radio Waves according to Propagation MechanismRadio Refractivity and Delay through the AtmosphereTropospheric AerosolsRain CharacteristicsPropagation of Radio Waves: An OutlineIntroductionPower Gain of Directional AerialFree Space Field Due to Directional Transmitting AerialPower at the Receiving Directional AerialFree Space Transmission LossRadio Waves in Neutral AtmosphereWhen Is a Medium a Conductor or Dielectric?Wave PolarizationReflection and Interference of Radio WavesIntroductionReflection of Radio Waves: An OutlinePlane Wave at Dielectric InterfaceReflection Coefficient for Flat Smooth EarthField Strength Due to Reflection from Flat EarthEffect of the Earth’s Curvature: Spherical EarthMechanism of Ground Wave PropagationRadio Refraction and Path DelayIntroductionRadius of Curvature of the Ray PathRefractivity Is Complex and Frequency DependentTurbulence-Induced ScintillationMicrowave Propagation through Tropospheric TurbulencePropagation over Inhomogeneous SurfaceTropospheric DuctingPropagation Delay through the AtmosphereAbsorption of MicrowavesIntroductionAbsorption CoefficientMicrowave and Millimeter Wave Absorption in the AtmosphereCentrifugal DistortionWater Vapor Absorption at 22.235 GHzWater Vapor Absorption at 183.311 GHzWater Vapor and Microwave AttenuationChoice of FrequencyAttenuation Studies in 50-70 GHz BandAttenuation Studies at 94 GHzRain Attenuation and Its Application at MicrowavesIntroductionRadiometric Estimation of Rain AttenuationITU-R Rain Attenuation Model and Its ApplicabilityRaindrop Size Distribution in the Tropics Attenuation by Hydrometeors Other than RainSnowHailFogAerosolsClouds: Nonprecipitable Liquid WaterMicrowave Radiometric Estimation of Water Vapor and Cloud LiquidEffect of Water Vapor and Liquid Water on Microwave SpectraCloud Radar Appendix: Mean Atmospheric Temperature at Microwaves and Millimeter Waves in Clear Air Environment

Pranab Kumar Karmakar obtained his MSc in physics in 1979 and PhD in the area of microwave propagation and remote sensing in 1990 from the University of Calcutta, India. Associated with the Department of Radiophysics and Electronics at Calcutta University since 1988, he is involved in both teaching and research work. He has more than forty-five publications in national and international journals of repute. Karmakaralso has more than thirty conference articles to his credit. He was awarded the Young Scientist Award of URSI (International Union of Radio Science) in 1990. He has been a visiting scientist at the Remote Sensing Lab, University of Kansas; Centre for Space Science, China; and Satellite Division, National Institute for Space Research (INPE), Brazil. He has also been awarded the South-South fellowship of TWAS (The Academy of Sciences for the Developing World) in 1997.Karmakar’s current area of research includes microwave/millimeter wave propagation, microwave remote sensing, and atmospheric modeling.