| 摘要 |
PURPOSE:To improve the operation precision of AGC by setting automatically an operation region of digital AGC in accordance with a peak factor. CONSTITUTION:An input digital signal (x) is supplied to a peak detecting circuit 11, an average power operating circuit 12, and a multiplier 15, and a peak value Pk and an average power PW are applied to an adder 13, and a difference signal AP=Pk-PW is outputted and is applied to a reciprocal generating circuit 14, and a coefficient 1/AP=Ax is outputted and is applied to the multiplier 15. When the peak value Pk is large, the coefficient Ax is small, and therefore, the average power of the input signal (x) to AGC loops 1 and 10 is small, and saturation of the peak value of an output digital signal (y) is avoided. When the peak value Pk is small, the coefficient Ax is large, and the average power of the input signal (x) to AGC loops 1 and 10 is large, and the operation precision of AGC loops 1 and 10 is improved. |
