Overhead energy considerations for efficient routing in wireless sensor networks

Abstract

Energy is the most critical resource in the life of a wireless sensor node. Therefore, its usage must be optimized to maximize the network life. It is known that for higher path loss exponent values, utilizing shorter communication links reduces the transmitter energy, whenever the radio equipment has power adjustment capability. Although the transmitter energy is one of the major factors of total energy dissipation, neglecting the overhead energy could result in suboptimal energy usage. Routing algorithms should also be concerned about the overhead energy which is wasted at each hop of data transfer. In this paper, we investigate the use of multi-hop communication links and compare the amount of energy gain upon alternative routes using analytical techniques. We show that employing multi-hop links does not always result in energy gain, and try to quantify situations when it is advantageous. The analytical results are used in routing decisions and their effect in energy efficiency is validated using simulations. Moreover, we also quantify the gain achieved in terms of lifetime by considering overhead energy on power adjustable sensors for different environmental conditions. We show that the network lifetime can dramatically decrease, if the overhead energy component is neglected during routing decisions.