PHY-MAC cross-layer approach to energy-efficiency improvement in low-power communications

This paper presents the improvement of energy-efficiency in low-power communications by joint usage of transmission power control, packet length optimization and packet aggregation techniques. We find that there are optimal transmission power and packet length for each channel condition (within operating range) and control data overhead that minimize energy per transmitted bit of data. Since optimal packet length strongly depends on control data overhead, we employ packet aggregation technique to reduce control data and additionally improve the efficiency. This approach shows more than 60% of energy savings, compared to transmissions of short packets with maximal available transmission power.