Accession Number : ADD008385

Title :   Variable Resistance Attenuator.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE ARMY WASHINGTON DC

Personal Author(s) : Abajian,Anthony

Report Date : 05 Aug 1980

Pagination or Media Count : 6

Abstract : An object of the invention is to provide a variable resistance attenuator having linear phase response, low insertion loss and constant attenuation over a broad range of frequencies. A feature of the invention relates to the use of at least four PIN diodes as an attenuator coupled to radio-frequency input and output circuits via at least one quadrature hybrid, with adjustable direct-current bias of the diodes to vary the attenuation. Two diodes are in parallel, oppositely directed, from each of two ports of the hybrid, at which the power from the input port is equally divided. Another feature relates to adjustable resistance and capacitance which serve as variable adjustments on the terminations of the quadrature hybrid. These variable elements permit the matching of the effective terminations to the characteristic impedance of the hybrid. This permits maximization of the attenuation range.

Descriptors :   *Patents, *Attenuators, *Pin diodes, Hybrid systems, Direct current, Linear systems, Insertion loss, Dynamic range, Phase(Electronics), Low loss, Response, Circuits, Capacitance, Linearity, Resistance, Output, Attenuation, Diodes, Input, Radiofrequency, Bias, Inventions, Constants, Variables

Subject Categories : Electrical and Electronic Equipment
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE