Sensor Data Curve fitting problem in realtime

Greetings,

I am developing a position sensor, after filtering my sensor data I am still getting a nonlinear drift in my readings, The sensor data after a 360 degrees of rotation is a sine shape function. Also, I am getting a feedback from a motor encoder which is plotted over my sensor signal and there I can see that there is a drift in the readings due to assembly tolerances most likely. Is there a way to Curve fit my sensor data if I have a recorded cycle of a correct data from the motor encoder?

What I want to achieve is to correct my data in runtime based on a pre stored Curve. (the key here is to Curve fit while the sensor is in operation) (delays are not important)

I appreciate your help.