Analog-to-digital conversion and harmonics due to the angular positioning error in magnetic field measurement

Analog-to-digital conversion pertaining to the rotating coil-based magnetic field measurement systems requires an angular positioning as a sample-timing reference, which inherently introduces unwanted harmonics due to the positioning jitter. We have adopted two practical models for the positioning jitter: a random positioning and a systematic positioning errors. For each positioning error, we analyzed the magnitude of the harmonics. Further, we have introduced a positioning correction scheme to reduce the unwanted harmonics, and analyzed the reduced magnitude to show its significance or the multipole measurement system design