High linear dynamic range magnetometer utilizing a large array of serially connected SQUIDS

A 7104-element serially connected SQUID array magnetometer has been designed and tested. The array had a measured magnetic field to voltage transfer function dV/dB of 1.2/spl times/10/sup 5/ volt/Tesla and a peak to peak modulation voltage of 0.6 volt. The sensitivity of the array magnetometer is 105 fT/Hz/sup 1/2/ at 20 kHz, and is limited by the 1/f noise of SQUIDs. The effective signal collection area of the array is 0.018 cm/sup 2/. The measured dynamic range of the array is 126 dB.