Abstract: A multichannel weak magnetic field measuring system for neuromagnetic diagnosis is provided having a plurality of dc-SQUID magnetometers. Bias current setting circuits are provided for detecting an even harmonic component of the output across the terminals of the corresponding SQUID and automatically adjusting a DC bias current to the SQUID. Accordingly, the level of the component becomes a predetermined value. Circuitry is also included for equalizing the magnetic flux detection sensitivities of these dc-SQUID magnetometers. Abnormal operation detecting circuits are also provided for producing abnormal operation detected outputs when the level of the corresponding even harmonic component is smaller than a certain threshold value.

Abstract: A digital signal weighting processing apparatus and method comprising a sampling section responsive to a measurement start signal for starting the measurement of an input signal and outputting sample values, a sample value storage section for storing these sample values in synchronism with each measurement of a single time, a weighting coefficient generation section for receiving said sample values each time the measurement of a single time is made, discriminating the magnitude of respective sample values and calculating weighting coefficients for each measurement of a single time, a weighting coefficient storage section for storing the weighting coefficients of each measurement of a single time outputted from the weighting coefficient generation section by the number of times of measurement, and a weighting section for successively reading out sample values at the same sampling time point each time the measurement of a single time is made and weighting the sample values by weighting coefficients correspondin