Modern Small Antenna Engieering

In this paper, small antennas (SA) are treated with a wide concept, in which not only electrically small antennas (ESA), but also SA's categorized in terms of dimensions and functions are included. Essentials of SA are discussed pertaining to the fundamentals of SA and realization of SA. Matching and resonance are taken as the significant issues in SA. Investigation of the radiation mechanism of an antenna system and study of the calculation of energy flow from an antenna are proposed as one of the clues to look into the essentials of SA. Typical structures to create ESA are shown and some practical examples of SA are introduced. Future perspectives are briefly discussed.