An Energy-Efficient Bit Allocation Scheme in Wireless Sensor Networks

Energy efficient transmission and bit allocation schemes are investigated in multi-source single-sink wireless sensor networks (WSN). For transmission in AWGN channels with path loss, this work shows that the overall energy consumption can be saved if each source transmits using its minimum power and cooperates with other sources in TDMA mode. From the source coding perspective, the Slepian-Wolf coding theorem is applied for efficient bit allocation since sources are usually highly correlated in WSN. Combining these two parts, we propose a closed form bit allocation scheme to minimize the overall energy consumption by assigning more bits to the nodes with better channel conditions. Based on this scheme, we further extend the network lifetime through a heuristic algorithm to average the energy consumption among all sensors.