A signal-processing unit according to the present invention comprises: an input line provided with a plurality of analog input signal lines; a multiplexer circuit transmitting the plurality of analog signals from this input line to one signal line in the subsequent stage in a desired sequence; an analog-digital conversion circuit that converts an analog signal into a digital signal and outputs it; and a cross talk compensation circuit that with respect to each of signals having been sequentially outputted from the analog-digital conversion circuit, a coefficient of an effect level between this signal and the other plural signals interfering with each other is calculated, and data obtained by multiplying the signals by these coefficients are added up.