  A high-accuracy calibration of inductive coil sensors based on Printed
Circuit Board (PCB), commonly used in rotating coil field measurements of
particle accelerator magnets, is presented. The amplitude and phase of signals
with and without main field suppression are compared in order to simultaneously
determine both the PCB rotation radius and the transverse offset of its plane
from rotation center. The accuracy of planar wire placement on the PCB boards
is exploited to create loops highly precise in area which rotate at different
radii. Such an area reproducibility and circuit geometry allow the suppression
of the fundamental field, enabling the calibration, as well as improving signal
resolution and mitigating vibration effects. Furthermore, the calibration can
be performed dynamically, in-situ during measurements. Calibration accuracy is
validated experimentally by referencing the PCB positions with a Coordinate
Measuring Machine (CMM).
