3,102 research outputs found
Throughput optimization strategies for large-scale wireless LANs
Thanks to the active development of IEEE 802.11, the performance of wireless local area networks (WLANs) is improving by every new edition of the standard facilitating large enterprises to rely on Wi-Fi for more demanding applications. The limited number of channels in the unlicensed industrial scientific medical frequency band however is one of the key bottlenecks of Wi-Fi when scalability and robustness are points of concern. In this paper we propose two strategies for the optimization of throughput in wireless LANs: a heuristic derived from a theoretical model and a surrogate model based decision engine
Improving Energy Efficiency Through Multimode Transmission in the Downlink MIMO Systems
Adaptively adjusting system parameters including bandwidth, transmit power
and mode to maximize the "Bits per-Joule" energy efficiency (BPJ-EE) in the
downlink MIMO systems with imperfect channel state information at the
transmitter (CSIT) is considered in this paper. By mode we refer to choice of
transmission schemes i.e. singular value decomposition (SVD) or block
diagonalization (BD), active transmit/receive antenna number and active user
number. We derive optimal bandwidth and transmit power for each dedicated mode
at first. During the derivation, accurate capacity estimation strategies are
proposed to cope with the imperfect CSIT caused capacity prediction problem.
Then, an ergodic capacity based mode switching strategy is proposed to further
improve the BPJ-EE, which provides insights on the preferred mode under given
scenarios. Mode switching compromises different power parts, exploits the
tradeoff between the multiplexing gain and the imperfect CSIT caused inter-user
interference, improves the BPJ-EE significantly.Comment: 19 pages, 10 figures, EURASIP Journal on Wireless Communications and
Networking; EURASIP Journal on Wireless Communications and Networking (2011)
2011:20
- …