The propagation of waves along and across the boundary between two media with different characteristic velocities is much more complicated when the source is on or near the boundary than when it is far away and the incident waves are plane. Examples of waves generated by localized sources near a boundary are the electromagnetic waves from the currents in a dipole on the surface of the earth and the seismic waves from a slip event in a fault in the earth's crust like the San Andreas fault in California. Both involve a type of surface wave that is called a lateral wave in electro magnetics and a head wave in seismology. Since the two are analogous and the latter is more easily visualized, it is conveniently used here to introduce and describe this important type of surface wave using the data of Y. Ben Zion and P. Malin ("San Andreas Fault Zone Head Waves Near Parkfield, CA," Science 251, 1592-1594, 29 March 1991)."

Cylindrical arrays lie at the heart of the antenna systems of most major radio communication systems, including broadcasting networks, cellular 'phone systems and radar. In this book, the authors present practical theoretical methods for determining current distributions, input admittances and field patterns of a wide variety of cylindrical antennas, including the isolated antenna, the two-element array, the circular array, curtain arrays, Yagi and log-periodic arrays, planar arrays and three-dimensional arrays. Coverage includes analysis of horizontal antennas over, on and in the earth and sea, large resonant arrays of electrically short dipoles and a chapter on the theory and techniques of experimental measurement. Written by three of the leading engineers in the field, and based on world-class research carried out at Harvard over the last forty years, Cylindrical Antennas and Arrays is destined to become established as the basic reference for practising engineers and advanced students for many years to come.

Cylindrical arrays lie at the heart of the antenna systems of most major radio communication systems, including broadcasting networks, cellular phone systems and radar. Here, the authors present practical theoretical methods for determining current distributions, input admittances and field patterns of a wide variety of cylindrical antennas. Key chapters cover analysis of horizontal antennas over, on and in the earth and sea; large resonant arrays of electrically short dipoles; and the theory and techniques of experimental measurement. Written by three of the leading engineers in the field, this reference is based on research carried out at Harvard over the last 40 years.