| 摘要 |
<p>APPLICATION OF ARTHUR M OLSEN METHOD OF COMPENSATING AN AMPLIFIER SYSTEM HAVING A VARIABLE GAIN AMPLIFIER TO ACHIEVE A CONSTANT OVERALL SYSTEM SIGNAL GAIN AND AN APPARATUS UTILIZING THE SAME A variable gain amplifier is adjusted to maintain its amplification within a linear range i.e., to prevent saturation of the amplifier, by utilizing the output of an analog-to-digital converter, which is arranged to convert an analog output of the amplifier to a digital representation, by a digital computer to effect the gain change of the amplifier. Concurrently, the output signal of the digital computer representing the output signal from the analog-to-digital converter is modified to produce a system output signal based on a constant overall gain of the system which is equivalent to the highest available gain from the amplifier. Thus, while the amplifier gain is adjusted by the computer in response to the amplitude of the input signal, the overall system gain is maintained at a level which would be available at the highest amplifier gain. The digital output of the system can subsequently be utilized as a control signal either directly or after a digital-to-analog conversion</p> |
