Abstract: There is provided a demodulator that makes it possible to reduce or avoid deterioration in demodulation performance due to nonlinearity of input amplitude-frequency characteristics of a variable capacitive element included in an analog control signal input section of a frequency variable oscillator, while suppressing an influence of noise. The demodulator includes: a low-resolution A/D converter that performs analog-digital conversion of a first phase difference signal to generate a second phase difference signal that is digital; a low-resolution D/A converter that performs digital-analog conversion of the second phase difference signal to generate a third phase difference signal; an analog subtractor that subtracts the third phase difference signal from the first phase difference signal to generate a first control signal; an ADPLL that generates a second control signal; and an FVO that generates the oscillation signal on the basis of the first control signal and the second control signal.

Abstract: There is provided a demodulator that makes it possible to reduce or avoid deterioration in demodulation performance due to nonlinearity of input amplitude-frequency characteristics of a variable capacitive element included in an analog control signal input section of a frequency variable oscillator, while suppressing an influence of noise.

Abstract: A signal transmission system includes: a transmitting section including a first carrier signal generating section configured to generate a carrier signal for modulation and a first frequency converting section configured to generate a transmission signal by frequency-converting a transmission object signal by the carrier signal for modulation, the carrier signal for modulation being generated by the first carrier signal generating section; and a receiving section including a second carrier signal generating section configured to generate a carrier signal for demodulation and a second frequency converting section configured to frequency-convert the transmission signal received by the carrier signal for demodulation, the carrier signal for demodulation being generated by the second carrier signal generating section.

Abstract: A signal transmission system includes: a transmitting section including a first carrier signal generating section configured to generate a carrier signal for modulation and a first frequency converting section configured to generate a transmission signal by frequency-converting a transmission object signal by the carrier signal for modulation, the carrier signal for modulation being generated by the first carrier signal generating section; and a receiving section including a second carrier signal generating section configured to generate a carrier signal for demodulation and a second frequency converting section configured to frequency-convert the transmission signal received by the carrier signal for demodulation, the carrier signal for demodulation being generated by the second carrier signal generating section.