Patent ID: 6448866
Filing Date: 2002-09-10
Classification: H01P,H03H

Abstract:
A circuit for the variable attenuation of microwave signals, comprising:a first coupler; a second coupler; a first series circuit of inductors, each inductor having a defined inductance, where one end of said first series circuit is connected to a first terminal of said first coupler, and the other end of said first series circuit is connected to a first terminal of said second coupler; a second series circuit of inductors, each inductor having a defined inductance, where one end of said second series circuit is connected to a second terminal of said first coupler, and the other end of said second series circuit is connected to a second terminal of said second coupler; a plurality of controllable resistance means, each being connected to a junction point between two respective inductors of said first or second series circuit; and inductors at the ends of said first and second series circuits having a predetermined inductance represented as L, the remaining inductors having an inductance 2L, and said first and second series circuits satisfying Z02=2L/C, where the characteristic impedance of said first coupler is represented as Z0, and the capacity of said controllable resistance means is represented as C.