Tuyển tập các báo cáo nghiên cứu khoa học ngành toán học được đăng trên tạp chí toán học quốc tế đề tài: Outage-optimal opportunistic scheduling with analog network coding in multiuser two-way relay networks | Upadhyay and Prakriya EURASIP Journal on Wireless Communications and Networking 2011 201 1 194 EURASIP Journal on http content 2011 1 194 Wireless Communications and Networking a SprIngerOpen Journal RESEARCH Open Access Outage-optimal opportunistic scheduling with analog network coding in multiuser two-way relay networks Prabhat K Upadhyay1 and Shankar Prakriya2 Abstract This paper investigates the performance of an outage-optimal opportunistic scheduling scheme for a multiuser two-way relay network wherein an analog network coding-based relay serves multiple pairs of users. Under a Rayleigh flat-fading environment we derive an exact expression for cumulative distribution function CDF of the minimum of the two end-to-end instantaneous signal-to-noise ratios SNRs and utilize this to obtain an exact expression for the outage probability of such a greedy scheduling scheme. We then develop a modified scheduler that ensures fairness among user pairs of the considered system. By using a high SNR approximation of derived CDF we present a simple closed-form expression for outage probability of the overall system and establish that a multiuser diversity of order equal to the number of user pairs is harnessed by the scheme. We also present an efficient power allocation strategy between sources and relay subject to a total power constraint that minimizes the outage probability of the overall system. Further by deriving both upper and lower bound expressions for the average sum-rate of the proposed scheme we demonstrate that an average sum-rate gain can also be achieved by increasing the number of user pairs in the system. Numerical and simulation results are presented to validate the performance of the proposed scheme. Keywords Analog network coding Multiuser scheduling Outage probability Rayleigh fading Two-way bidirectional relaying 1 Introduction Cooperative relaying techniques have recently gained great research interest because of their .
