Energy Efficiency of Network-Coded Cooperation in Underwater Acoustic OFDMA Communications with Subcarrier Allocation

In this work we evaluate the energy efficiency (EE) of some recently proposed network-coded cooperative (NCC) schemes based on orthogonal frequency division multiple access (OFDMA) in an underwater acoustic network (UWAN) subjected to Generalized K fading. Our analysis also encompasses the frequency-dependent attenuation typical of the UWA channel, and considers the actual energy consumption of some currently available acoustic modems, including the circuitry consumption. As a result, we show that the appropriate choice of the frequency and the number of cooperative users is fundamental towards maximizing the EE.