"The authors ... have done a marvelous job in collecting the relevant material, and presenting it in a coherent and easily readable form. ... There is no doubt that this new book fills a real need, and will be of great benefit to students, researchers, and engineers who enter the fields of radio exploration of the ionosphere, space weather, radio-frequency planning, spectrum management, and radio-system design. For those already working in these areas, it will provide valuable context." (Bodo Reinisch, The Radio Science Bulletin, Issue 353, June, 2015)