This document describes the process and equations for a Kalman filter. It initializes the state estimate, covariance matrix, and linearizes the state and measurement models. It then enters a iterative process of predicting the state, computing the measurement prediction, calculating the Kalman gain, and updating the state estimate and covariance matrix based on the difference between the predicted and actual measurements. The process linearizes models, computes the mean square error of prediction, and adjusts the prediction according to weighted ratios of predicted and state errors.