Patent ID: 11949394
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A phase shifter comprising:
a 90-degree distributor to divide an input signal into four signals including a first signal, a second signal having a phase difference of 90 degrees from the first signal, a third signal having a phase difference of 180 degrees from the first signal, and a fourth signal having a phase difference of 270 degrees from the first signal; a first phase shift circuit to amplify each of any three signals from among the first signal to the fourth signal in accordance with a phase shift amount of an output signal to the input signal when a frequency of the input signal is included in a first frequency band, and output a synthesized signal of the three amplified signals; and
a second phase shift circuit to amplify, when a frequency of the input signal is included in a second frequency band that does not overlap with the first frequency band and is continuous with the first frequency band, each of any two signals of the any three signals and one signal that is not amplified by the first phase shift circuit from among the first signal to the fourth signal in accordance with the phase shift amount, and output a synthesized signal of the three amplified signals,
wherein one or more phase shift circuits of the first phase shift circuit and the second phase shift circuit each include a compensation circuit that compensates for a phase error of a synthesized signal,
wherein in a case where the first phase shift circuit includes the circuit compensation circuit, and when the frequency of the input signal is an upper limit frequency of the first frequency band, an RMS (Root Mean Square) of the phase error of the synthesized signal output from the first phase shift circuit is smaller than an RMS of the phase error of the synthesized signal output from a phase shift circuit including the first phase shift circuit and the second phase shift circuit including the compensation circuit,
in a case where the second phase shift circuit includes the circuit compensation circuit, and when the frequency of the input signal is a lower limit frequency of the second frequency band, an RMS of the phase error of the synthesized signal output from the first phase shift circuit is smaller than an RMS of the phase error of a synthesized signal output from a phase shift circuit including the first phase shift circuit and the second phase shift circuit each of which includes the compensation circuit.