Correction and interpolation of position encoders

The present invention relates generally to position referencing devices and more particularly relates to techniques for correcting systematic errors found in commercial position encoders and for accurately extrapolating encoders to higher resolution. The present invention provides a method for referencing the position of a moving component. The method includes generating a first signal in response to the relative movement between a first sensor and encoder strip having a repeating pattern of fiducial marks, the first signal including a plurality of transitions corresponding to the repeating pattern; generating a second signal in response to the relative movement of a second sensor and the encoder strip, the second signal including a plurality of transitions corresponding to the repeating pattern; estimating a position of the moving component based upon the transitions within the first sensor signal; and identifying a direction of movement of the moving component in response to the first and second signals.