Physical and MAC cross-layer analysis of energy-efficient MIMO networks

Abstract

In this paper we study the energy efficiency of multiple antennas (MIMO) networks considering both the physical (PHY) and the medium access control (MAC) layers. At the PHY layer, the transmit power determines the communication rate and the area containing nodes that contend for channel access. In turn, accessing the channel takes additional time and energy at the MAC layer, which impacts the throughput and the energy efficiency. Moreover, we focus in slow fading scenarios, so that we remodel former cross-layer models in order to be representative of quasi-static MIMO networks, in which we employ the e-capacity as the system metric. In addition, we analyze the impact of antenna selection (AS) and singular value decomposition (SVD) beamforming MIMO diversity transmission schemes in terms of throughput and energy efficiency. Results show that SVD has smaller delay and higher throughput; however, this scheme is significantly outperformed in terms of energy efficiency by AS.