| 摘要 |
PURPOSE:To apply the system to a measuring signal in which the 1st order lag time constant is fluctuated, by obtaining a logarithm of a difference between the measuring signal and its forecasting final value and feedback-controlling the forecasting value so that the logarithm can be a linear function of time. CONSTITUTION:A difference btween an output signal of an amplifying circuit 3 and a present value x(t) of a measuring signal is logarithmically converted at a logarithmic conversion circuit 1, and this logarithmic converting value is second- order-differentiated at a differentiation circuit 2. This differentiated value is amplified at the amplifying circuit 3 and fed back to the input of the circuit 1 and outputted as the forecasting final value of the measuring signal. When this circuit system is in balancing state, the input signal to the circuit 3 is minimized. Since the gain of the circuit 3 is sufficiently high, the input signal can actually be regarded as zero. This means that the output signal of the circuit 1 is a linear function of time. Thus, the output signal of the circuit 3 at the balancing state is coincident with the final value of the signal x(t). That is, the forecasting value of the final value is obtained. |
