Patent ID: 6236161
Filing Date: 2001-05-22
Classification: H01J

Abstract:
A crossed-field device such as a crossed-field amplifier, said device including a peripheral cathode body portion having an emitter surface with a yield of electrons to enable sustained operation thereof and also having an anode portion spaced about said peripheral cathode portion such that an electric field is provided between said cathode portion and said anode portion in a gap along an interaction slow wave traveling region in which a magnetic crossed field cooperates to maintain emitted electrons on cycloidal pathways as the electrons travel between an inlet and an outlet of said crossed-field amplifier;said inlet for providing a microwave frequency input signal for amplification by interaction with said electrons;said outlet, for carrying an amplified microwave frequency signal from said device;a control electrode positioned away from said slow-wave traveling region at a drift region, said control electrode being operable for interrupting sustained emission to shut down the device between working cycles; andan auxiliary electrode positioned internally of said peripheral cathode and positioned proximally of said control electrode for defining a secondary electron trap;whereby biasing said auxiliary electrode reduces energy required on said control electrode.2.The crossed-field device of claim 1, wherein the peripheral cathode body portion is comprised of a material having a secondary electron emission ratio greater than unity.