| 摘要 |
A signal gain controlled system is disclosed for impressing a gain, as a function of the level of a control signal, on an input signal to the system. The system is of the type including a first signal converter for providing a first signal as a function of the logarithm of the input signal. The first signal converter comprises (a) an amplifier, (b) means in the feedback path of the amplifier for providing, in response to the input signal, a first signal as a function of the logarithm of the input signal. The system also includes a second signal converter coupled to the output of the amplifier for providing an output signal in response to the first signal and as a function of the algebraic summation of the first signal and the control signal. The improvement comprises amplification means coupled to the output of the amplifier and responsive to the output signal of the amplifier for amplifying the first signal as a function of the output signal of the amplifier. |
