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: Research Article A Novel Method for Improving Fairness over Multiaccess Channels | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2010 Article ID 395763 10 pages doi 2010 395763 Research Article A Novel Method for Improving Fairness over Multiaccess Channels Seyed Alireza Razavi and Ciprian Doru Giurcaneanu Department of Signal Processing Tampere University of Technology . Box 553 33101 Tampere Finland Correspondence should be addressed to Seyed Alireza Razavi Received 7 June 2010 Accepted 29 November 2010 Academic Editor Jean-marie Gorce Copyright 2010 S. A. Razavi and C. D. Giurcaneanu. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. It is known that the orthogonal multiple access OMA guarantees for homogeneous networks where all users have almost the same received power a higher degree of fairness in rate than that provided by successive interference cancellation SIC . The situation changes in heterogeneous networks where the received powers are very disparate and SIC becomes superior to OMA. In this paper we propose to partition the network into almost homogeneous subnetworks such that the users within each subnetwork employ OMA and SIC is utilized across subnetworks. The newly proposed scheme is equivalent to partition the users into ordered groups. The main contribution is a practical algorithm for finding the ordered partition that maximizes the minimum rate. We also give a geometrical interpretation for the rate-vector yield by our algorithm. Experimental results show that the proposed strategy leads to a good tradeoff between fairness and the asymptotic multiuser efficiency. 1. Introduction and Preliminaries Rate allocation in multiuser communication systems is an important task which should consider simultaneously the fairness and the spectral efficiency. This paper is focused on fairness of .
