Compensation of electromagnetic interference fields

摘要

The system has three-axis magnetic field sensors (3, 4) outputting real sensor signals, and a regulator unit (7) with a digital processor e.g. digital signal processor, to receive the signals and to process control signals for compensation coils (6). The real signals are converted into virtual sensor signals by a matrix multiplication to form an interference field at a location of an object. The virtual signals are made to changed signals by an operator defining a regulator structure. The changed signals are converted into real control signals by another matrix multiplication fed to the coils.