媒體存取控制層(MAC)在感知網路中協定扮演一個相當重要的角色。儘管他在理論上面充分的被討論，但是實際應用在機器之上的論文仍然是少數。而那些實作類型的論文，也充分的將那些之前研究的感知網路理論應用在不同的場景。在我們的眼就當中，我們提出一個捨棄許多多餘機制的輕量型且適用於許多存取頻譜演算法的實作型論文。在這些頻譜演算法當中，我們除了可以實作同步以及非同步的跳頻演算法之外，我們也可以實作叢集型頻譜存取演算法。而這些演算法我們將利用GNU Radio和USRP的平台去實作。在實作當中，我們會針對實驗數據進行分析和探討，而這些將成為以後設計頻譜存取演算法的考量。而這樣子的實驗我們將在802.11的環境下進行。

Medium Access Control (MAC) protocol play a vital role in cognitive radio (CR). It is well-known that implementation of CR MAC is rare in this issue. There has been some papers which are implement CR MAC with different testbed and test it in different scenario. In our work, we propose a lightweight MAC protocol without complexity mechanism and it can verify various spectrum access algorithm which contains channel hopping algorithm or clustering algorithm in synchronous or not. With implementing on GNU Radio and Universal Software Radio Peripheral (USRP) platform, we discuss various design considerations and challenges of our MAC in experiment. Our experimental results presents the performance of each spectrum access algorithm which is running under PU which is run in 802.11 protocol.

[1] GNU Radio, “The GNU Software Radio,” http://www.gnu.org/software/gnuradio/.
[2] E. R. LLC., “The USRP Product Family Products and Daughter Boards,” http://www.ettus.com/products, 2011.
[3] L. Ma, X. Han and C.-C. Shen, “Dynamic Open Spectrum Sharing for Wireless Ad Hoc Networks,” in Proceeding of The Annual IEEE Symposium on New Frontiers in Dynamic Spectrum Access Networks (DySPAN), 2005.
[4] J. Jia, Q. Zhang and X. Shen, “HC-MAC: A Hardware-constrained Cognitive MAC for Efficient Spectrum Management,” IEEE J. on Selected Areas in Communications, vol. 26, no. 1, pp. 106-117, 2008.
[5] C. Cordeiro and K. Challapali, “C-MAC: A Cognitive MAC Protocol for Multichannel Wireless Networks,” in Proceeding of Symposium on Dynamic Spectrum Access Networks (DySPAN), 2007.
[6] J. Zhao, H. Zheng, and G.-H. Yang, “Distributed Coordination in Dynamic Spectrum Allocation Networks,” in Proceeding of The Annual IEEE Symposium on New Frontiers in Dynamic Spectrum Access Networks (DySPAN), 2005.
[7] S. Liu, L. Lazos, and M. Krunz, “Cluster-Based Control Channel Allocation in Opportunistic Cognitive Radio Network,” IEEE TRANSACTIONS ON MOBILE COMPUTING, 2012.
[8] K. R. Chowdhury and I. F. Akyildiz, “OFDM-Based Common Control Channel Design for Cognitive Radio Ad Hoc Networks,” in Proc. IEEE Transactions on Mobile Computing, vol. 10, no. 2, pp. 228-238, 2010.
[9] B. F. Lo, “A Survey of Common Control Channel Design in Cognitive Radio Networks,” Physical Communication, vol. 4, no. 1, pp. 26-39, 2011.
[10] P. Bahl, R. Chandra, and J. Dunagan, “SSCH: Slotted Seeded Channel Hopping for Capacity Improvement in IEEE 802.11 Ad-Hoc Wireless Networks,” in Proceeding of The Annual ACM International Conference on Mobile Computing and Networking (MobiCom), 2004.
[11] L. A. DaSilva and I. Guerreiro, “Sequence-Based Rendezvous for Dynamic Spectrum Access,” in Proceeding of The Annual IEEE Symposium on New Frontiers in Dynamic Spectrum Access Networks (DySPAN), 2008.
[12] K. Bian, J. Park, and R. Chen, “A Quorum-Based Framework for Establishing Control Channels in Dynamic Spectrum Access Networks,” in Proceeding of The Annual ACM International Conference on Mobile Computing and Networking (MobiCom), 2009.
[13] K.-G. Bian and J.-M. Park. “Asynchronous Channel Hopping for Establishing Rendezvous in Cognitive Radio Networks,” in Proceeding of The Annual IEEE International Conference on Computer Communication (INFOCOM), 2011.
[14] Y.-F. Zhang, Q. Li, G.-X. Yu, and B.-S. Wang, “ETCH: Efficient Channel Hopping for Communication Rendezvous in Dynamic Spectrum Access Networks,” in Proceeding of The Annual IEEE International Conference on Computer Communication (INFOCOM), 2011.
[15] Z.-Y. Lin and H. Liu, “Jump-Stay Based Channel-Hopping Algorithm with Guaranteed Rendezvous for Cognitive Radio Networks,” in Proceeding of The Annual IEEE International Conference on Computer Communication (INFOCOM), 2011.
[16] S. Romaszko and P. Mahonen, “Quorum-Based Channel Allocation with Asymmetric Channel View in Cognitive Radio Networks,” in Proceeding of ACM Workshop on Performance Monitoring and Measurement of Heterogeneous Wireless and Wired Networks (PM2HW2N), 2011.
[17] F. Seelig, “A Description of the August 2006 XG Demonstrations at Fort AP Hill,” in Proceeding of Symposium on Dynamic Spectrum Access Networks (DySPAN), 2007.
[18] M. McHenry, E. Livsics, T. Nguyen, and N. Majumdar, “XG Dynamic Spectrum Sharing Field Test Results,” in Proceeding of Symposium on Dynamic Spectrum Access Networks (DySPAN), 2007.
[19] S. Gu, P.-C. Xu, X.-B. Wang, X.-Y. Gan, and H. Yu, “A Real Time Testbed for the Evaluation of Cognitive Radio MAC,” in Proceeding of Annual IEEE Global Communication Conference (GLOBECOM), 2011.
[20] R.-L. Zhou, Q. Han, R. Cooper, V. Chakravarthy, and Z.-Q. Wu, “Software Defined Radio Based Adaptive Interference Avoidance TDCS Cognitive Radio,” in Proceeding of Annual IEEE International Conference on Communication (ICC), 2010.
[21] Y.-S. Huang, P. Walsh, Y.-H. Li and S.-W. Mao, “GNU Radio Testbed for Distributed Polling Service-based Medium Access Control,” in Proceeding of Annual IEEE Military Communications Conference, 2011
[22] J.-V. Greunen, and J. Rabaey, “Lightweight Time Synchronization for Sensor Networks,” in Proceedings of the 2nd ACM international conference on Wireless sensor networks and applications, 2003
[23] D. Yang, J. Shin, and C. Kim, "Deterministic Rendezvous Scheme in Multichannel Access Networks," Electronics Letters, vol. 46, no. 20, pp. 1402-1404, 2010.