Radio Wave Propagation

Radio Wave Propagation: Consolidated Summary Technical Report of the Committee on Propagation of the National Defense Research Committee presents all the scientific information and report of experiments. This book discusses the problems encountered in the propagation of radio waves.

Organized into three volumes, this book begins with an overview of the technical developments in the study of tropospheric propagation. This text then outlines the general theory of standard and nonstandard propagation together with descriptions and results of transmission experiments designed to test the theory. Other chapters consider the more unusual problems concerning the radar behavior of targets. This book discusses as well the problems of radio wave propagation in the standard atmosphere at frequencies above 30 megacycles. The final chapter deals with the selection and utilization of local terrain features that affect propagation and the performance of equipment.

This book is a valuable resource for scientists and engineers in the field of radio wave propagation.

Contenu

Volume I Technical Survey

Part I Summary

Chapter 1. Standard Propagation

Introduction

Power Transmission

Optical Properties of the Earth's Surface and Atmosphere

The Electromagnetic Field

Chapter 2. Elementary Theory Of Nonstandard Propagation

Historical

Refractive Index

Types of M Curves

Ray Tracing

General Characteristics of Ducts

Survey of Waveguide Theory

Reflection from Elevated Layers

Chapter 3. Meteorological Measurements

Introduction

Temperature and Humidity Elements

The Wired Sonde

Refractive Index Measurements

Other Meteorological Instruments

Representative Observed Curves

Chapter 4. Transmission Experiments

British Experiments

Experiments at the Eastern Coast of the U. S.

Experiments in Northwestern United States and Canada

Experiments in the Southwestern United States

Experiments at Antigua

Angle-of-Arrival Measurements

Chapter 5. General Meteorology And Forecasting

Introduction

Atmospheric Stratification

Conditions Over Land

Coastal and Maritime Conditions

Dynamic Effects

World Survey

Radar Forecasting

Chapter 6. Scattering And Absorption Of Microwaves

Absorption and Radar Cross Section

Aircraft Targets

Ship Targets

Absorption and Scattering by Clouds, Fog, Rain, Hail, and Snow

Part II Conference Reports On Standard Propagation

Chapter 7. A Graphical Method For The Determination Of Standard Coverage Charts

Chapter 8. Nomographic Solutions For The Standard Case

Chapter 9. Theoretical Analysis Of Errors In Radar Due To Atmospheric Refraction

Purpose

Procedure

Application to Ground Radar Equipments

Conclusions

Chapter 10. Diffraction Of Radio Waves Over Hills

Chapter 11. Siting And Coverage Of Ground Radars

Introduction

Radar Systems

Types of Ground Radar

Radar Systems - Tactical Aspects

Radar Siting - Technical Aspects

Topography of Siting

Introduction

Maps and Surveys

Profiles

Orientation

Visibility Problems

Diffraction of Radio Waves

Introduction

Wave Propagation

Fresnel Zones

Reflection from Rough Surfaces - Rayleigh's Criterion

Diffraction at Obstacles

Fresnel Integrals

The Cornu Spiral

Straight Edge Diffraction

Location of Maxima and Minima

The Rectangular Slit

Diffraction by a Narrow Obstacle

Multiple Slits and Obstacles

Limitations of Fresnel's Theory

Permanent Echoes

Introduction

Permanent Echo Diagrams

Use of Permanent Echoes in Testing

Shielding

Prediction of Permanent Echoes

Prediction by Profile Method

Microwave Permanent Echoes

The Calculation of Vertical Coverage

Introduction

The Vertical Coverage Diagram

Flat Earth Lobe Angle Calculations

Lobe Angles Corrected for Standard Earth Curvature

The General Lobe Angle Formula

The Calculation of Lobes

Low Site Lobes

Lobe Diagrams of Medium Height Sites

Shoreline Diffraction

Sea Reflection with Diffuse Land Reflection

General Formula for the Reflection Area

The Modified Antenna Pattern

Antenna Patterns

Local Terrain Effects

Earth Curvature Effect on Lobe Lengths

Coefficient of Reflection

Divergence

Lobe Lengths

The General Lobe Formula

Calibration and Testing

Equipment Tests

Signal Measurements

Conduct of Test Flights

Analysis of Test Data

Chapter 12. Variations In Radar Coverage

Bending

Guided Propagation

Meteorological Factors

Cloud Echoes in Radar

Summary of Basic Facts Concerning Propagation at Radar Frequencies

Part III Conference Reports On Nonstandard Propagation

Chapter 13. Tropospheric Propagation And Radio Meteorology

Fundamentals of Propagation

Significance of Propagation Problems

Factors Influencing Propagation

Reflection from the Ground

Refraction - Snell's Law

Refraction Over a Curved Earth

Equivalent Earth Radius - Flat Earth Diagram

The Horizon - Diffraction

Atmospheric Stratification and Refraction

Origin of Refractive Index Variations

The Measurement of Refractive Index

Types of Modified Index Curves

Rays in a Stratified Atmosphere

The Duct - Superrefraction

Wave Picture of Guided Propagation

Reflection from an Elevated Layer

Operational Applications

Radio Meteorology

Temperature and Moisture Gradients

Physical Causes of Stratification - Turbulence

Advective Ducts - Coastal Conditions

Ducts Over the Open Ocean

Nocturnal Cooling - Daily Variations

Fog

Subsidence - Dynamic Effects

Seasonal and Global Aspects of Superrefraction

Fluctuations in Signal Strength with Time

Scattering and Absorption by Water Drops

Snell's Law

Chapter 14. Theoretical Treatment Of Nonstandard Propagation In The Diffraction Zone

Chapter 15. Characteristic Values For The First Mode For The Bilinear M Curve

Chapter 16. Incipient Leakage In A Surface Duct

Calculations for the First Mode of the Bilinear Model

Calculations for the Second and Higher Modes of the Bilinear Model

Chapter 17. The Solution Of The Propagation Equation In Terms Of Hankel Functions

Chapter 18. Attenuation Diagrams For Surface Ducts

Chapter 19. Approximate Analysis Of Guided Propagation In A Nonhomogeneous Atmosphere

Chapter 20. Some Theoretical Results On Nonstandard Propagation

Propagation in the Oceanic Surface Duct

Characteristic Values for a Continuously Varying Modified Index

Chapter 21. Perturbation Theory For An Exponential M Curve In Nonstandard Propagation

Abstract

Introduction

Formal Solution of the Problem by the Perturbation Method

Evaluation of ßnm( ) as an Indefinite Integral

Properties of ßnm ( )

Iteration Method of Solving for the Characteristic Values Dk and the Coefficients Akm

Expansion of Dk into a Power Series in a

Applicability of Perturbation Method to a More General Class of Anomalies

Computational Program for the Exponential Model

Symbols for Use in Theory of Nonstandard Propagation

Chapter 22. First Order Estimation Of Radar Ranges Over The Open Ocean

Chapter 23. Convergence Effects In Reflections From Tropospheric Layers

Convergence Factor

Roughness Effect

Conclusions

Volume II Radio Wave Propagation Experiments

Part I Meteorology

Chapter 1. Meteorology - Theory

Modification of Warm…