Book excerpt: Practical Microwave Electron Devices provides an understanding of microwave electron devices and their applications. All areas of microwave electron devices are covered. These include microwave solid-state devices, including popular microwave transistors and both passive and active diodes; quantum electron devices; thermionic devices (including relativistic thermionic devices); and ferrimagnetic electron devices. The design of each of these devices is discussed as well as their applications, including oscillation, amplification, switching, modulation, demodulation, and parametric interactions. Numerous design examples and case studies are presented throughout the book. For each microwave electron device covered, typical design examples or case studies are presented as well as qualitative or quantitative explanations. The fundamental theory of each device is summarized along with the underlying principles of the design. Each summary is presented so that the design techniques can be applied to other specific cases, designs, and applications. Review questions are included with each chapter to stimulate creative thinking and enhance the acquisition of knowledge and design skills. This book is written for engineers, scientists, and technicians seeking practical knowledge on microwave electron devices and their applications through self-study. It is also suitable for use as a college textbook in upper-division courses for seniors and first-year graduate students in electrical engineering.