How to add the noise covariance matrix of my measurements to tmy 1D kalman filter?
If you are so new to Kalman filtering, the best first suggestion should be the most readable book on the topic: Fundamentals of Kalman Filtering, from Zarchan. 

In the mean time, the measurement noise covariance matrix $R$ is adjusted according to the a priori known (either empirically or theoretically) characteristics of the measurement device (the sensors). When these characteristics change during the operation time of the filter, then you would expectedly reflect that in an update of the measurement noise matrix $R$ according to the new settings. 

You will include this measurement noise covariance matrix into the Kalman update equations. Which previously using fixed $R$ will now be using variable $R$ matrix, as a matter of fact.