The Propagation of Radio Waves

This book is largely concerned with the ionosphere and the magnetosphere, and gives the theory of their effect on radio waves. It includes accounts of some mathematical topics that are now widely used in this study, particularly W.K.B. approximations, Airy integral functions and integration by steepest descents. The subject is in two main parts, usually called ray theory and full wave theory. The first is useful for high frequencies and includes ray tracing and caustic surfaces. The second is used for lower frequencies when the approximations of ray theory fail. Much of the book is concerned with the ionosphere treated as a horizontally stratified medium, but there is some discussion of the magnetosphere whose structure is more complicated. This includes an account of whistlers and ion cyclotron whistlers.The book has been planned both for final year undergraduates and as a reference book for research. It is suitable as a course book on radio propagation for students of physics or electrical engineering or mathematics. Some of the topics are presented from an elementary viewpoint so as to help undergraduates new to the subject. The later parts are more advanced. The subject is very large and has seen many important recent advances. Some topics have had to be treated only briefly, but there is a full bibliography with about 600 references.