| 摘要 |
PURPOSE:To demodulate the phase of a signal where the spectrum due to phase fluctuation and the spectrum due to amplitude fluctuation cannot be separated, by obtaining a reverse trigonometrical function of the momentary amplitude of the input signal and converting it to a momentary angle. CONSTITUTION:A momentary phase is denoted as theta(t) to express a momentary amplitude f(t) of an input signal applied to a terminal 1 with formula f(t)= Asintheta(t), and sin<-1>{f(t)1A}is operated by a converting circuit 4. The carrier is extracted by a carrier extracting circuit 5, and carrier components are eliminated from the momentary phase output theta(t) of the circuit 4 by a subtractor 6 to demodulate the phase. After demodulation, a switch 3 is switched to the (b) side to demodulate the phase of the demodulation wave repeatdly. Carrier components extracted by the circuit 5 are outputted as features of sounds. |
