Energy efficient transmission strategies for distributed detection in wireless sensor networks

In this paper, we propose two energy efficient ordered transmission schemes with fusion rules for distributed detection in wireless sensor networks (WSNs). The fusion rule at the fusion center (FC) has been derived to take into account not only the reliability of local decision at sensors, but also channel gains from sensors to the FC. In the first scheme, the sensors´ transmission order is based on only local log-likelihood ratio (LLR), while it is based on both the reliability of local decision and quality of transmission channels in the second scheme. Due to the ordered transmission, the target detection performance can be achieved with a small number of sensors, which leads to energy efficient distributed detection in WSNs. At the high signal-to-noise ratio (SNR) regime, the performances of both strategies converge to the best achievable one in the case that the sensors perfectly know the received signals at the FC.