Patent ID: 6078228
Filing Date: 2000-06-20
Classification: H03H

Abstract:
A phase shifting electric circuit comprising:a main signal input to which an alternating current input signal arrives;a main signal output from which an alternating current signal is transmitted;at least one phase shifting unit for shifting the phase of the outut signal relative to the input signal by about 180 degrees, the phase shifting unit comprising a signal input connected to the main signal input, and a signal output;a first electrically active unit comprising:a signal input connected to the main signal input; anda signal output connected to the main signal output;a second electrically active unit comprising:a signal input connected to the signal output of the phase shifting unit; anda signal output connected to the main signal output;an input impedance matching circuit, wherein the input impedance matching circuit is connected to the main signal input and is diretly connected to both the phase shifting unit and the first electrically active unit; andan output impedance matching circuit, wherein the output impedance matching circuit is connected to the main signal output and is directly connected to the signal outputs of both of said first and second electrically active units,wherein the first electrically active unit in its connected condition to the main signal output is arranged to output an output signal which has the same phase as the input signal, and the second electrically active unit in its connected condition to the main signal output is arranged to output an output signal which has a predetermined phase shift relative to the input signal, said phase shift being determined by the phase shifting unit; andwherein the first and second electrically active units each comprises an amplifier unit.