| 摘要 |
<p>PURPOSE:To eliminate the need for a square-law circuit and a square root circuit by deriving a shape parameter from the ratio of the maximum value of an input in a movement window and the mean value of the input. CONSTITUTION:A device 13 inputs an input signal X and detects the maximum amplitude of N (integer) samples within the moving window and a circuit 3a outputs the movement average of the signal X; and a circuit 4 outputs the logarithm of the signal X and a circuit 3b sends out the mean average of the output signal of the circuit 4 as the 1st output and the output of the circuit 4 which is delayed by a half as long as the movement average width as the 2nd output. Further, a divider 5 divides the output of the circuit 3a by the output of the device 13 and outputs the quotient Q=f(a) as a specific equation, a computing element 6a inputs the quotient Q to send out -gamma/f<-1>(Q) [gamma: Euler's constant, f<-1>(Q): inverse function] as the 1st output and f<-1>(Q)/2 as the 2nd output, and an adder 7 adds the 1st output of the circuit 3b and the 1st output of the computing element 6a together; and a subtracter 8 subtracts the output of the adder 7 out of the 2nd output of the circuit 3b, a multiplier 9 outputs the product of the output of the subtracter 8 and the 2nd output of the computing element 6a, and a circuit 10 outputs the inverse logarithm of the output of the multiplier 9.</p> |
