Exploiting Error Estimating Codes for Packet Length Adaptation in Low-Power Wireless Networks

We propose Plena, a packet length adaptation scheme exploiting recently proposed error estimating codes (EEC) for low-power wireless networks. We carefully consider two low-power MAC protocols in modeling the energy consumption of different packet lengths. Based on the modeling and analysis, we give closed form solutions for the optimal packet length in terms of energy efficiency. EEC allows for instant estimation of the bit error rate (BER) in a partially correct packet, making it possible for predicting packet reception ratios (PRRs) at different packet lengths without the need of direct measurement in an iterative process. Fast convergence of Plena makes it suitable for mobile environments in which the channel characteristics are frequently changing. We evaluate Plena's computation overhead based on the commonly used TelosB nodes. Results show that the computation overhead of Plena is acceptably small. We also perform extensive simulations and testbed experiments to study the performance of Plena under different configurations. Results show that Plena achieves better energy efficiency than existing works.