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Current Status and Further Progress in the Smith-Purcell Amplifiers Research

Results are reviewed of an theoretical and experimental study of the Smith-Parcel amplifiers over the millimeter-and sub millimeter wave bands. The fundamentals of constructing such devices are discussed, the most promising design being pointed out. Two main leads for further research are supported in this fields, namely, development of the low-noise low-signal amplifiers and power relativistic-and nonrelativistic-beam amplifiers. On the basis of the theory developed, particle-field interaction in such devices are analyzed in details and the limiting output characteristics are estimated.