SIGNAL PROCESSING APPARATUS FOR PROCESSING TIME VARIANT SIGNAL WITH FIRST AND SECOND INPUT SIGNALS COMPRISING A WEIGHTING CORRELATOR AND A FIRST GAIN-ADJUSTABLE AMPLIFIER

A signal processing apparatus receiving a first input signal and the first input signal being directly used as a first output signal. The signal processing apparatus comprising: a first gain-adjustable amplifier receiving the first input signal and generating a gain-adjusted first input signal according to a gain; a first adder for subtracting the gain-adjusted first input signal from the second input signal, thereby generating a second output signal; and a weighting correlator receiving the first output signal and the second output signal, and generating the first integrated signal to control the gain.