A new approach to collaborative ranging using received signal strength indicator in wireless sensor network

In general, the distance between two sensor nodes can be estimated by converting received signal strength indicator value to distance using path loss prediction model. Since the received signal strength indicator values are mostly expressed in decibel form, thus antilog function is used to convert dBm to normal scale of power. This causes large variation at output when input has small variation. Any error happens at input is amplified at output. To solve this problem, this paper presents a novel approach to Collaborative Ranging (CR) using received signal strength indicator (RSSI) in wireless sensor network. This approach estimates distance directly using received signal strength indicator values without converting dBm to normal scale. Therefore, the maximum number involved in the computation is confined so that it does not exceed the limit of a 16-bit processor can support. The results show that the proposed method provides excellent performance to reduce the error caused by inaccurate parameters obtained from characterization phase. The overall root mean square error is smaller than the result obtained from normal path loss model.