Cross-Layer Energy-Efficiency Optimization of Packet Based Wireless MIMO Communication Systems

Abstract

Energy in today's short-range wireless communication is mostly spent on the analog-and digital hardware rather than on radiated power. Hence, purely information-theoretic considerations fail to achieve the lowest energy per information bit and the optimization process must carefully consider the overall transceiver. In this paper, we propose to perform cross-layer optimization, based on an energy-aware rate adaptation scheme combined with a physical layer that is able to properly adjust its processing effort to the data rate and the channel conditions to minimize the energy consumption per information bit. This energy proportional behavior is enabled by extending the classical system modes with additional configuration parameters at the various layers. Fine grained models of the power consumption of the hardware are developed to provide awareness of the physical layer capabilities to the medium access control layer. The joint application of the proposed energy-aware rate adaptation and modifications to the physical layer of an IEEE 802.11n system, improves energy-efficiency (averaged over many noise and channel realizations) in all considered scenarios by up to 44%.

Characterizing the Energy-Efficiency Region of Symbiotic Radio Communications

“…Note that for the special case when ĝ = 0, problem (14) reduces to the EE maximization problem of the conventional point-to-point channel, whose optimal solution is obtained in [20], [21]. For the more general problem (14), the optimal solution is obtained in the following Theorem.…”