Variable phase shifter, semiconductor integrated circuit and phase shifting method

摘要

A variable phase shifter. The variable phase shifter includes: a transmission line that outputs quadrature signals from a pair of output ports in response to an input signal of a specific frequency; a synthesizer that includes a first transistor connected to a first port of the pair of output ports and a second transistor connected to a second port of the pair of output ports, and that on input of the input signal takes signals output from the pair of output ports of the transmission line with a phase according to their respective load impedances and employs the first and the second transistors to amplify and combine the signals; and a phase controller that controls the phase of the output signal that is combined and output by the synthesizer by controlling the amplification operation of each of the first and second transistors of the synthesizer.

主权项

1. A variable phase shifter, comprising:
a transmission line that outputs quadrature signals from a pair of output ports in response to an input signal of a specific frequency; a synthesizer that includes a first transistor connected to a first port of the pair of output ports and a second transistor connected to a second port of the pair of output ports so that parasitic capacitance of the first transistor and the second transistor becomes load impedance for the transmission line, and that inputs signals output from the pair of output ports of the transmission line with a phase difference according to their respective load impedances, on input of the input signal, to the first transistor and the second transistor and combines the signals, which are amplified and output by the first transistor and the second transistor; and a phase controller that controls the phase of the output signal that is combined and output by the synthesizer by controlling the amplification operation of each of the first and second transistors of the synthesizer.