Abstract: The current paper considers the problem of Mobile Terminal (MT) positioning based on a time series of Received Signal Strength (RSS) measurements and provides statistical estimators of the MT- Base Station (BS) distance which substantially improve the MT positioning accuracy. The set of MT-BS distance estimators defined for optimizing RSS based positioning developed in  is used as a basis. The problem that is analyzed refers to the adaptation of these estimators to the presence of Kalman filtering in the MT position calculation process. Three different Kalman filtering options can be applied at different stages of the MT position calculation process : (a) RSS Kalman filtering, (b) MT-BS distance Kalman filtering and (c) MT position coordinates Kalman filtering. To identify the optimal MT-BS distance estimators at the presence of Kalman filtering a method exploiting the characteristics of the steady state Kalman filter performance is developed. This novel method allows for the definition of refined MT-BS distance estimators matching the nature of the Kalman filter process. The results indicate that the resulting estimators provide good efficiency for all Kalman Filter options.