A wide-bandwidth high-gain small-size distributed amplifier with field-emission triodes (FETRODEs) for the 10 to 300 GHz frequency range

Author

Kosmahl, Henry G.

Author_Institution

Hughes Aircraft Co., Torrance, CA, USA

Volume

36

Issue

11

fYear

1989

fDate

11/1/1989 12:00:00 AM

Firstpage

2728

Lastpage

2737

Abstract

It is demonstrated that, by a suitable modification of the well-known thin-film field-emission cathode (TFFEC) of C.A. Spindt (1948, 1976) into a FETRODE, a vacuum-type free-electron amplifier with a figure of merit superior to that achieved with triodes and FETs can be established. Analytical evaluation of important parameters of the FETRODE and the distributed amplifier´s circuit is carried out. A formula for the RF efficiency of the FETRODE is applied to an approximate relation between the output current and the input RF voltage that gives the dependence of efficiency on the ratio of the RF output impedance and the DC beam impedance. Potential advantages of future FETRODEs over solid-state FETs are discussed, assuming already established DC current emission levels as well as improved levels resulting from low-work-function materials other than Mo cones.

Keywords

cold-cathode tubes; electron field emission; microwave amplifiers; microwave tubes; triodes; wideband amplifiers; 10 to 300 GHz; DC beam impedance; EHF; FETRODE; MM-wave device; Mo cones; RF efficiency; RF output impedance; SHF; distributed amplifier; field-emission triodes; free-electron amplifier; high-gain; input RF voltage; microwave tubes; output current; vacuum-type; wide-bandwidth; Broadband amplifiers; Cathodes; Distributed amplifiers; FETs; Impedance; Radio frequency; Radiofrequency amplifiers; Solid state circuits; Thin film circuits; Voltage;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.43780

Filename

43780