tailieunhanh - Báo cáo toán học: " Tight performance bounds for two-way opportunistic amplify-and-forward wireless relaying networks with TDBC protocols"

Tuyển tập các báo cáo nghiên cứu khoa học ngành toán học được đăng trên tạp chí toán học quốc tế đề tài: Tight performance bounds for two-way opportunistic amplify-and-forward wireless relaying networks with TDBC protocols | Jia et al. EURASIP Journal on Wireless Communications and Networking 2011 2011 192 http content 2011 1 192 o EURASIP Journal on Wireless Communications and Networking a SpringerOpen Journal RESEARCH Open Access Tight performance bounds for two-way opportunistic amplify-and-forward wireless relaying networks with TDBC protocols Xiangdong Jia1 2 3 Longxiang Yang2 3 4 and Haiyang Fu2 3 Abstract Based on amplify-and-forward network coding AFNC protocol the outage probability and ergodic capacity of two-way network coding opportunistic relaying TWOR-AFNC systems are investigated as well as the corresponding closed-form solutions. For the TWOR-AFNC systems it is investigated under two scenarios namely the TWOR-AFNC systems without direct link TWOR-AFNC-Nodir and the TWOR-AFNC systems with direct link TWOR-AFNC-Dir . First we investigate TWOR-AFNC-Nodir systems by employing the approximate analysis in high SNR and obtain closed-form solutions to the cumulative distribution function CDF and the probability density function PDF of the instantaneous end-to-end signal-to-noise ratio SNR with very simple expressions. The derived simple expressions are given by defining an equivalent variable ffleq-k ớ 2 Ỡ 3. When Ỡ 2 the derived results are the tight lower bounds to CDF and PDF. The sequent simulation demonstrates that the derived tight lower bounds are also very effective over the entire SNR region though which the results are derived in high SNR approximation. Then with the derived tight closed-form lower bound solutions Ỡ 2 in TWOR-AFNC-Nodir systems we investigate TWOR-AFNC-Dir systems as well as the overall comparison of the outage probability and the ergodic capacity between the two system models. The comparison analysis performed over path loss model basis shows that in urban environment due to utilizing the direct link the TWOR-AFNC-Dir outperform considerably the TWOR-AF-Nodir systems. However when the value of path loss exponent is relatively