Cross-Layer Designs for Energy-Efficient Wireless Ad-hoc Networks

Abstract

Energy consumption is an important design criteria for wireless networks, not least because it directly impacts the cost of network operation and maintenance. Already, the information and communication technology (ICT) industry is being labeled as a substantial contributor to the total CO\(_2\) emissions on the planet. Moreover, due to the slow improvement in battery technology, battery-operated wireless networks face a fundamental challenge, since there is an exponential increase in the gap between the demand for energy and the offered battery capacity. For these reasons, green ICT has become a critical issue world wide. This chapter adopts a cross-layer approach for enhancing the energy efficiency of wireless ad-hoc networks. Initially, the chapter discusses the importance of cross-layered designs for energy-efficient wireless networks. Following this, commonly used techniques for modeling energy consumption in wireless networks are outlined. Lastly, cross-layer designs based on cooperative physical layer network coding and hybrid automatic repeat request (HARQ) are presented. In this cross-layered design approach, energy-efficient transmission strategies are initially proposed for the physical (PHY) and medium access control (MAC) layers. Then, these optimized strategies are utilized as basic building blocks for energy-efficient routing at the network layer. All of the theoretical results are verified through computer simulations.