No system in science or engineering can be successfully designed, analysed and specified unless it is backed up by precise quantitative measurements. This is particularly difficult in the field of microwaves where, more often than not, the parameter(s) of interest cannot be observed directly but must be inferred from the measurement of other related parameters. Although the advent of the automated network analyser has eliminated much of the previous drudgery, the problems of interpreting the digitally displayed information still remain. One purpose of this book is to provide the reader with a thorough understanding of the microwave circuit model and its limitations, and thus eliminate the many potential pitfalls that otherwise await the unwary experimenter. Starting with the field equations, the book first outlines the theoretical basis for microwave circuit theory with particular emphasis on its similarity to, and difference from, the low frequency counterpart. This leads to an identification of the parameters to be measured and is followed by a survey of measurement methods with emphasis on the 'why' in addition to 'how'. Special emphasis is given to 'power equation methods', adapter evaluation, the six-port network analyser and noise. In these areas in particular, the book includes recently developed material that has not been previously published.

During his tenure of more than 30 years at the National Bureau of Standards, Glenn F. Engen has published over forty papers in the field of microwave metrology. His contributions to the art have been recognised by Department of Commerce Gold and Silver Medals, the NBS Applied Research Award, the (Instrumentation and Measurement) Society Award, the Woodington Award for Professionalism in Metrology, the IEEE membership rank of Fellow and the ARFTG Automated Measurement Career Award.