This book describes the fundamentals of THz communications, spanning the whole range of applications, propagation and channel models, RF transceiver technology, antennas, baseband techniques, and networking interfaces. The requested data rate in wireless communications will soon reach from 100 Gbit/s up to 1 Tbps necessitating systems with ultra-high bandwidths of several 10s of GHz which are available only above 200 GHz. In the last decade, research at these frequency bands has made significant progress, enabling mature experimental demonstrations of so-called THz communications, which are...

This book includes the description, modeling and realization of new optical metrology techniques for technical diagnostics of materials. Special attention is paid to multi-step phase shifting interferometry with arbitrary phase shifts between interferograms, phase shifting and correlation digital speckle pattern interferometry, optical-digital speckle correlation, and digital image correlation, as well as dynamic speckle patterns analysis.Optoacoustic techniques can be treated as a separate branch of optical metrology and can solve many problems of technical diagnostics, including detection...

Classical asymptotic expansions, while producing a good approximation for the diffracted fields in general, appear hardly applicable in the case of extremely elongated bodies. Thus, there are problems that are on the one hand too difficult for numerical solvers due to large system size, and on the other hand make the description with classical asymptotic methods hard. The book explains why this happens and suggests the way out. By defining the characteristics of a strongly elongated body it introduces a special class of asymptotic approximations, which are in some sense uniform with respect...