Patent ID: 8645097

Claim:
Method of analyzing output from an incremental rotary sensor, comprising the steps of: (a) obtaining a unique reference signal measured from the rotary sensor; (b) receiving output from the rotary sensor, the sensor output includes a plurality of individual pulses that are generally uniform in pulse-width and have some discrepancies; (c) calculating a duty cycle for each of the plurality of individual pulses that are generally uniform in pulse-width; (d) averaging the plurality of duty cycles over a number of revolutions, wherein the averaged duty cycles cause periodic content of the sensor output to be distinguishable from aperiodic content of the sensor output; and (e) identifying periodic irregularities in the averaged duty cycles of the sensor output, wherein a vehicle electronic module compares the periodic irregularities in the averaged duty cycles of the sensor output to the reference signal to determine the absolute angular position of the rotary sensor even though the plurality of individual pulses are generally uniform in pulse-width.