| 摘要 |
PURPOSE:To correctly demodulate an information signal by controlling a phase modulating means to phase-modulate a reference signal from a reference signal generating means in accordance with the change direction of the output amplitude of a multiplying means. CONSTITUTION:The output of a multiplying means 14 to multiply an input signal and a code from a code preparing means 13 is extracted and held at a prescribed timing and compared with the output of the multiplying means 14 extracted before one timing. Based on the compared result, the phase relation of the input signal and the code from the code generating means 13 is decided and a phase modulating means 12 to output the reading clock signal of the code generating means 13 is controlled so as to synchronize the input signal and the code. Thus, without using a voltage control type oscillator, the synchronizing accuracy and demodulating accuracy can be improved. |
