Patent ID: 7126442
Filing Date: 2006-10-24
Classification: H03H

Abstract:
1. A phase shifter comprising: (i) a plurality of phase shift units serially connected, each comprising a reactance unit including a first variable capacitance device, wherein the reactance unit is connected to an adjacent reactance unit, and a susceptance unit including a second variable capacitance device, connected to said reactance unit, wherein the reactance unit, the adjacent reactance unit, and the susceptance unit form a T-section, and wherein the first variable capacitance device and the second variable capacitance device have a capacity ratio such that the first variable capacitance device and the second variable capacitance device are controllable by a common control signal; and (ii) a control unit for outputting the common control signal to said phase shift units, wherein said control unit outputs the control signal so as to maintain the following expression constant: wherein Z