Abstract：The Received Signal Strength Indicator (RSSI)based nodes localization algorithms are extensively applied in wireless sensor networks. Due to the influence of wireless signal attenuation and the channel barrier shielding, the localization accuracy of these algorithms are not high. A grid divisionbased probabilistic localization algorithm was put forward. This new algorithm first divided the area where the unknown nodes may exist into a number of grids. Then, it calculated out the confidence of every grid under the assumption that the unknown node was just in that grid. Finally, it calculated out the coordinates of the unknown node based on several geometric centers of the grids of high confidence. The localization result of this algorithm is less influenced by the noise pollution and is of high position accuracy.
