In this paper, we investigate a multiuser cognitive relay network with direct source-destination links and multiple primary destinations. In this network, multiple secondary users compete to communicate with a secondary destination assisted by an amplify-and-forward (AF) relay. We take into account the availability of direct links from the secondary users to the primary and secondary destinations. For the considered system, we select one best secondary user to maximize the received signal-to-noise ratio (SNR) at the secondary destination. We first derive an accurate lower bound of the outage probability, and then provide an asymptotic expression of outage probability in high SNR region. From the lower bound and the asymptotic expressions, we obtain several insights into the system design. Numerical and simulation results are finally demonstrated to verify the proposed studies.
|Title of host publication||Communications (ICC), 2014 IEEE International Conference on|
|Editors||Abbas Jamalipour, Der-Jiunn Deng|
|Publisher||Institute of Electrical and Electronics Engineers (IEEE)|
|Number of pages||6|
|Publication status||Published - 2014|
Lei, X., Hu, R. Q., Duong, T. Q., Fan, L., & Elkashlan, M. (2014). Multiuser Cognitive Relay Networks in the Presence of Direct Links. In A. Jamalipour, & D-J. Deng (Eds.), Communications (ICC), 2014 IEEE International Conference on (pp. 4342-4347). Institute of Electrical and Electronics Engineers (IEEE). https://doi.org/10.1109/ICC.2014.6884003