Phase-difference-corresponding-value measurement device, gain imbalance measurement device, method, program, and recording medium

TL;DR: In this article, the authors proposed a modulation error measurement device that includes an I-frequency-phase deriving unit 14 I which derives the phase of a component of an I frequency (ω 1 ) of the demodulated signal, an opposite-sign I-fraction-phase derived unit (I-FPDU) which derives a phase of an opposite sign I frequency (−ω 1 ), and a Q-frequency phase derived unit 14 Q-fDRU (Q-FDRU).

Abstract: A modulation error measurement device according to the present invention receives a demodulated signal containing a demodulated I signal and a demodulated Q signal from a quadrature demodulator receiving an RF signal output by a quadrature modulator and applying the quadrature demodulation to the received RF signal, and measures a quadrature error corresponding to a phase difference between an I component and a Q component of the modulated signal. The quadrature modulator applies quadrature modulation to an original I signal (ω 1 ) and an original Q signal (ω 2 ) having frequencies different from each other. The modulation error measurement device includes an I-frequency-phase deriving unit 14 I which derives the phase of a component of an I frequency (ω 1 ) of the demodulated signal, an opposite-sign I-frequency-phase deriving unit which derives the phase of a component of an opposite-sign I frequency (−ω 1 ) of the demodulated signal, a Q-frequency-phase deriving unit which derives the phase of a component of a Q frequency (ω 2 ) of the demodulated signal, and an opposite-sign Q-frequency-phase deriving unit which derives a phase of a component of an opposite-sign Q frequency (−ω 2 ) of the demodulated signal.