本論文提出資源分配法來解決在有限資源限定下，中繼微型基地台網路中的中繼點選擇及資源分配之問題，將其產能達到最大化。然而當在考量有限資源分配時，要求得在此條件下最佳情形的資源分配，其時間複雜度過高，造成在執行決策時，其執行時間過長。因此我們提出了一個啟發式演算法，此方法大大的降低了在執行決策的時間，並且同時其產能也相當接近於最佳化的情形，我們將會在模擬的結果中證實我們提出的啟發式演算法，可以節省大量執行的時間，然後比較在最佳情形及啟發式之產能差異程度，證實出兩個方法在產能上是相當接近的。

This study presents an algorithm to solve the relay selection and resource assignment under the threshold constraint to maximize the throughput for relay based femtocell network. However the time complexity of proposed optimal algorithm costs too much time to make the decision. Therefore, we propose a heuristic algorithm. This algorithm largely reduces the time of making the decision compared to the optimal case and throughput achieves close to the optimal case. The simulation result shows that the propose method can largely save the execution times with the small difference of throughput compared to the optimal case. By using the proposed heuristic algorithm, we greatly reduce the execution time and maintain high system performance for the resource assignment.

[1] V. Chandrasekhar, J. G.Andrews, A. Gatherer, and T. Instruments, "Femtocell Networks: A Survey," IEEE Commun. Mag., vol. 46, no.9, pp. 59-67, Sept. 2008.
[2] P.Jacob and A. S. Madhukumar, "Interference reduction through femto-relays," IEEE IET Communications, vol. 2, no., pp. 2208-2217 Sept . 2012.
[3] P.Jacob and A. S. Madhukumar, "Femto-relays: a power efficient coverage extension mechanism for femtocells," IEEE Int. Symp. on Personal Indoor and Mobile Radio Communication (PIMRC), vol., no., pp 975-979, Sept. 2011.
[4] D. Zhou and W. Song, "Interference-Controlled Load Sharing with Femtocell Relay for Macrocells in Cellular Networks," In: Proc. of Global Telecommunications Conference (GLOBECOM) IEEE, vol., no., pp.1-5, Dec. 2011
[5] J. Kiblida, M. Kucharzak, M. Filo, and R. Piesiewicz, "Energy Efficient Mobile Relay Service in Future Networks," IEEE Future Network & MobileSummit 2012 Conference Proceedings, vol., no., pp. 1-8,July. 2012.
[6] Y. Yang, H. Hu, J. Xu, and G. Mao, "Relay Technologies for WiMAX and LTE-Advanced Mobile Systems," IEEE Communications Magazine, vol., no., pp. 100-105, Oct. 2009.
[7] Y. Liu and M. Tao, "Optimal Channel and Relay Assignment in OFDM-Based Multi-Relay Multi-Pair Two-Way Communication Networks," IEEE Transactions on Communications, vol. 60, no. 2, pp. 317-321, Feb. 2012.
[8] A. Rath, S. Hua, and S. S.Panwar, "FemtoHaul: Using Femtocells with Relays to Increase Macrocell Backhaul Bandwidth," IEEE Conference on Computer Communications Workshops, vol., no., pp. 1-5, Mar. 2010.
[9] P. Makris, N. Nomikos, D. N. Skoutas, D. Vouyioukas, C. Skianis, J. Zhang, et al., "A context-aware framework for the efficient integration of femtocells in IP and cellular infrastructures," EURASIP Journal on Wireless Communications and Networking, Mar. 2013.
[10] N. Nomikos, P. Makris, N. Skout, D. Vouyoukas and C. Skianis, "A cooperation Framework for LTE Femtocells' Efficient Integration in Cellular Infrastructures Based on Femto Relay Concept," IEEE 17th International Workshop on Computer Aided Modeling and Design of Communication Links and Networks (CAMAD), vol., no. , pp. 318-322, Sept. 2012.
[11] I. F.Akyildiz, E. Chavarria-Reyes, D. M. Gutierrez-Estevez, R. Balakrishnan, and J. R.Krier, "Enabling next generation small cells through femtorelays," ELSEVIER Physical Communication, vol. 9, no., pp. 1-15, Apr. 2013.
[12] A. T. Gamage, M. S. Alam, X. Shen, and J. W. Mark, "Joint Relay, Subcarier and Power Allocation for OFDMA-based Femtocell Networks," IEEE Wireless Communications and Networking Conference (WCNC), vol., no., pp. 679-684, Apr. 2013.
[13] M. S. Alam, Jon W. Mark and X. Shen, "Relay Selection and Resource Allocation for Multi-User Cooperative OFDMA Networks," IEEE Transactions on Wireless Communications, vol. 12, no., pp. 2193-2205, May 2013.
[14] H. Zhang, Y. Liu, and M. Tao, "Resource Allocation with Pairing in OFDMA Two-Way Relay Networks," IEEE Wireless communications Letters, vol. 1, no. , pp. 61-64, Apr. 2012.
[15] W. Dang, M. Tao, H. Mu, and J. Huang, "Subcarrier-Pair Based Resource Allocation for Cooperative Multi-Relay OFDM Systems," IEEE Transactions on Wireless Communications, vol. 9, no., pp. 1640-1649, May 2010.
[16] G. Li and H. Liu, "Resource Allocation for OFDMA Relay Networks With Fairness Constraints," IEEE Journal on Selected Areas in Communications, vol. 24, no., pp. 2061-2069, Nov. 2006.
[17] S.B.Lande, S.P.Shende, and S.S.Pathak, "Strategic Subvarrier Allocation for Cooperative OFDMA Relaying Network," IEEE International Conference on Electronic Systems, Signal Processing and Computing Technologies, vol., no., pp. 178-183, Jan. 2014.
[18] G. Munasinghe and D. Jayalath, "Subcarrier Pairing and Relay Assignment With Improved User Fairness in a Multi-user Cooperative OFDM System," IEEE, Telecommunication Networks and Applications Conference (ATNAC), vol., no., pp. 1-4, Nov. 2012.
[19] R. A. Loodaricheh, S. Mallick, and V. K.Bhargava, "Distributed Subcarrier Pairing and Relay Selection for OFDM based Cooperative Relay Networks," IEEE Wireless Communications and Networking Conference (WCNC), vol., no., pp. 3557-3562, Apr. 2013.
[20] Y. L. M. Tao, "An Optimal Graph Approach for Optimizing OFDMA Relay Networks," IEEE ICC Wireless Communications Symposium, vol., no., pp. 4277-4281, Jun. 2012.
[21] Z. H. A. Jamalipour and V. K.Bhargava, "Cooperative Communication and Relay Selection Under Asymmetric Information," IEEE Wireless Communications and Networking Conference (WCNC): Mobile and Wireless Networks, vol., no., pp. 2373-2378, Apr. 2012.
[22] Z. Hasan and V. K. Bhargava, "Relay Selection for OFDM Wireless Systems under Asymmetric Information: A Contract-Theory Based Approach," IEEE International Transactions on Wireless Communications, vol.12, no., pp. 3824-3827, Aug. 2013.
[23] L. Xiao, T. E. Fuja, and D. J. Costello, "An Analysis of Mobile Relaying for Coverage Extension," Information Theory, 2008. ISIT 2008. IEEE International Symposium on, vol., no., pp. 2262-2266, July 2008.
[24] L. Xiao, T. E. Fuja, and D. J. Costello, "Mobile Relaying: Coverage Extension and Throughput Enhancement," IEEE Transactions on Communications, vol. 58, no., pp. 2709-2717, Sept. 2010.