Accurate positioning method of the trapped personnel based on Calman filter algorithm

In the indoor positioning system, serious multipath and ranging errors caused by non-line-of-sight phenomena become more significant. Thus, taking measures to reduce the influence of ranging errors on localization accuracy is a key issue in indoor positioning systems. In this paper, with respect to a wireless positioning system using ZigBee technology architecture, the trilateral measurement method, a localization algorithm based on distance measuring RSSI value and the Calman filter are optimized. This makes full use of the Calman filter's prediction, and by introducing a new factor in the prediction equation, errors are reduced, allowing more accurate location information to be returned.