Báo cáo sinh học: Improving energy efficiency through multimode transmission in the downlink MIMO systems

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: mproving energy efficiency through multimode transmission in the downlink MIMO systems
Nội dung trích xuất từ tài liệu:
Báo cáo sinh học: "Improving energy efficiency through multimode transmission in the downlink MIMO systems"EURASIP Journal on WirelessCommunications andNetworking This Provisional PDF corresponds to the article as it appeared upon acceptance. Fully formatted PDF and full text (HTML) versions will be made available soon. Improving energy efficiency through multimode transmission in the downlink MIMO systems EURASIP Journal on Wireless Communications and Networking 2011, 2011:200 doi:10.1186/1687-1499-2011-200 Jie Xu (suming@mail.ustc.edu.cn) Ling Qiu (lqiu@ustc.edu.cn) Chengwen Yu (chengwen.yu@huawei.com) ISSN 1687-1499 Article type Research Submission date 22 February 2011 Acceptance date 9 December 2011 Publication date 9 December 2011 Article URL http://jwcn.eurasipjournals.com/content/2011/1/200 This peer-reviewed article was published immediately upon acceptance. It can be downloaded, printed and distributed freely for any purposes (see copyright notice below). For information about publishing your research in EURASIP WCN go to http://jwcn.eurasipjournals.com/authors/instructions/ For information about other SpringerOpen publications go to http://www.springeropen.com © 2011 Xu et al. ; licensee Springer.This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1 Improving energy efficiency through multimode transmission in the downlink MIMO systems Jie Xu1 , Ling Qiu∗1 and Chengwen Yu21 Personal Communication Network & Spread Spectrum Laboratory (PCN&SS), University of Science and Technology of China (USTC), Hefei, 230027 Anhui, China 2 Wireless research, Huawei Technologies Co. Ltd., Shanghai, China ∗ Corresponding author: lqiu@ustc.edu.cn Email addresses: JX: suming@mail.ustc.edu.cn CY: chengwen.yu@huawei.com Abstract 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 article. 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, in which 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 into the preferred mode under given scenarios. Mode switching compromises different power parts, exploits the trade- off between the multiplexing gain and the imperfect CSIT caused inter-user interference and improves the BPJ-EE 2 significantly. Keywords: Bits per-Joule energy efficiency (BPJ-EE); downlink MIMO systems; singular value decomposition (SVD); block diagonalization (BD); imperfect CSIT. 1. Introduction Energy efficiency is becoming increasingly important for the future radio access networks due to the climatechange and the operator’s increasing operational cost. As base stations (BSs) take the main parts of the energyconsumption [1, 2], improving the energy efficiency of BS is significan ...