Two-stream instability – linear and nonlinear microwave phenomena. Part I

This article is the first of two parts of the review devoted to the phenomenon of two-beam instability in microwave electronics. The main goal is to cover as much as possible the most complete list of papers on various models and methods of analysis of the two-beam instability. The first part contains papers which, in our view, most fully describe the development of ideas of two-stream instability in microwave electronics. Among these works there are some pioneering works which laid the foundation for research in this field, as well as numerous research articles aimed at expanding the application field of this phenomenon. The first part covers the time period from the date of the first publication on the subject, beginning the 40-ies of the last century, to the time when the interest of researchers in this field began decreasing significantly, the end of the 90-ies of the last century. The second part covers the most relevant works on the application of two-stream instability in microwave electronics, released over the past few years. These studies have confirmed the growing interest of foreign researchers to this phenomenon, and that was the impetus for the creation of this review.