Energy Consumption Reduction of a WSN Node Using 4-bit ADPCM

摘要

A 4-bit adaptive differential pulse-code modulation (ADPCM) scheme applied to the sensor data of a Zigbee based wireless sensor network node is shown to decrease the energy consumption of the analog front-end of the node by 58%. Simulation results from an energy model of an 802.15.4 based analog front-end show that the energy consumed by the network node is inversely proportional to the number of bits used to encode the digital data. The quantization error of a 4-bit ADPCM scheme is on average -14 dB for low frequency data and only 3 dB higher than a traditional 8-bit PCM scheme. By modifying the modulation scheme in the software with no modification of the hardware, the lifetime of the node can be increased significantly with minimal modifications.