Various embodiments provide for systems and methods for signal conversion of one modulated signal to another modulated signal using demodulation and then re-modulation. According to some embodiments, a signal receiving system may comprise an I/Q demodulator that demodulates a first modulated signal to an in-phase (“I”) signal and a quadrature (“Q”) signal, an I/Q signal adjustor that adaptively adjusts the Q signal to increase the signal-to-noise ratio (SNR) of a transitory signal that is based on a second modulated signal, and an I/Q modulator that modulates the I signal and the adjusted Q signal to the second modulated signal. To increase the SNR, the Q signal may be adjusted based on a calculated error determined for the transitory signal during demodulation by a demodulator downstream from the I/Q modulator.

A calibration circuit and a calibration method for a phase shifter, a phase-shift circuit, a radio frequency transmitting circuit, a radio frequency receiving circuit, a radar sensor and an electronic device are provided. The calibration circuit for the phase shifter includes a phase acquisition circuit and a phase calibration circuit, the phase acquisition circuit coupled to the phase shifter is configured to modulate a radio frequency sample signal acquired from the phase shifter using a first baseband signal, down-convert the modulation signal to obtain a second baseband signal containing an actual phase; the phase calibration circuit coupled to the phase acquisition circuit is configured to acquire the actual phase in the second baseband signal, determine calibration phase information according to a phase deviation between the actual phase and a preset phase-shift phase, generate a phase-shift control signal according to calibration phase information and transmit it to the phase shifter.

Various embodiments provide for systems and methods for signal conversion of one modulated signal to another modulated signal using demodulation and then re-modulation. According to some embodiments, a signal receiving system may comprise an I/Q demodulator that demodulates a first modulated signal to an in-phase (I) signal and a quadrature (Q) signal, an I/Q signal adjustor that adaptively adjusts the Q signal to increase the signal-to-noise ratio (SNR) of a transitory signal that is based on a second modulated signal, and an I/Q modulator that modulates the I signal and the adjusted Q signal to the second modulated signal. To increase the SNR, the Q signal may be adjusted based on a calculated error determined for the transitory signal during demodulation by a demodulator downstream from the I/Q modulator.