无线自组网MAC协议关键技术研究
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
近年来,随着研究的深入和相关硬件技术的发展与成熟,无线自组网技术在实际应用中得到越来越多的部署。无线自组网是由无线通信节点通过分布式协议连接而成的系统,具有独立性、多跳性、分布性和移动性等特点。介质访问控制协议(Media Access Control,MAC)是无线自组网协议栈的重要组成部分,决定了节点如何通过共享的无线空间信道发送和接收报文。MAC协议能否高效的利用有限的无线信道资源对无线自组网的性能有决定性的影响。
     基于随机竞争的MAC协议开销低,适合在无线自组网环境下单个节点上实现且实现开销不高,因而成为无线自组网MAC协议研究中最主流的技术。作为基于随机竞争的无线自组网MAC协议最典型和最成功的代表,IEEE 802.11协议在研究和实际应用中使用最为广泛。但是,IEEE 802.11通过RTS/CTS控制报文预约信道的通信方式牺牲了邻近节点可能的并发传输机会,导致网络的吞吐量不高。无线自组网共享信道的接入方式决定了节点在通信过程中不可避免的面临流内竞争乃至流间竞争,而IEEE 802.11协议处理这些MAC竞争不够完善是导致其在无线自组网多跳环境下性能不够理想的主要原因。
     围绕无线自组网MAC协议性能优化这个关键问题,本文深入分析了影响MAC协议性能的本质原因,针对现有工作存在的对并发传输支持不够理想、对流内竞争和流间竞争等MAC层竞争处理不够完善等不足之处,提出了相应的解决方法。
     本文主要工作包括:
     1.MAC层并发传输机制研究。在无线自组网中,在给定区域内同时进行的传输越多,则整个系统的吞吐量就越高。因而,在确保彼此不破坏对方传输的前提下,在一定的空间范围内调度尽可能多的传输是提高无线自组网MAC协议吞吐量的有效途径之一。在无线自组网中,无线通信节点在接收报文时可以容忍一定程度的干扰存在,这就是无线通信所特有的捕获效应。利用无线通信的这一内在特征,本文基于现有符合IEEE 802.11规范的硬件,提出一种用于无线自组网的并发传输MAC协议——CTMAC。
     为了实现并发传输,CTMAC协议在控制报文和数据报文间插入附加控制时隙,并让节点在成功交换控制报文后进行相应的等待,直到附加控制时隙结束才开始数据报文的发送。配合附加控制时隙机制的引入,CTMAC协议的控制报文只是有条件的使邻居节点静默,以便邻居节点有更多的机会交换控制报文并调度传输。为了确保并发调度的传输可以互不干扰的成功进行,本文对RTS/CTS控制报文机制进行扩展,并在控制报文中引入必要的冲突避免信息作为并发调度的依据。为了更充分的利用无线自组网内潜在的并发机会,本文提出一种新颖的ACK报文串行化机制,有效隔离了不同传输的DATA报文和ACK报文,在提高协议并发度的同时极大的简化了协议的设计。由于附加控制时隙的长度对协议的性能有重要的影响,本文提出一种附加控制时隙自适应调整技术,节点可以通过报文级的调整对周围的情况做出及时的反应,优化自己的行为。模拟结果表明,CTMAC协议突破了传统的基于CSMA/CA机制的MAC协议对并发传输的限制,在网络中存在并发可能时明显的提高了系统的吞吐量。
     2.多跳通信环境下流内竞争问题研究。无线自组网分布、自组的特性决定了其中的流量以多跳流量为主。多跳通信路径上的相邻节点不可避免的面临流内竞争问题,制约了MAC协议的性能。本文在深入分析多跳通信流本质特征的基础上,着眼于流内竞争问题的解决,提出主动等待MAC协议——VWMAC。VWMAC协议采用一种自我克制策略,节点在成功发送DATA报文后根据所发送DATA报文的长度和与多跳路径上邻近节点的位置关系主动的等待一段时间,并在等待期间切换到睡眠状态以节约宝贵的电池能量。本文得出了节点主动等待时长计算的经验公式,并通过模拟实验进行正确性验证。模拟结果显示,VWMAC协议较好的解决了流内竞争问题,与已有协议相比,VWMAC提高了多跳通信流的端到端吞吐量,降低了端到端延迟并改善了节点的能源使用效率。
     3.MAC层竞争动态处理机制研究。在MAC层,无线自组网节点同时面临流内竞争和流间竞争等多种竞争。对竞争和冲突的处理是否及时和主动在很大程度上决定了MAC协议的性能。针对传统的二进制指数回退机制存在的问题,本文提出一种动态等待MAC协议——DWMAC,使节点根据自己所面临竞争的激烈程度动态的调整自己参与无线信道竞争的行为。DWMAC协议下,节点在成功发送DATA报文后将主动进行等待,等待时长由节点动态的根据其面临的竞争程度和相邻节点所声明的信道占用时间决定。在动态等待期间,节点放弃对信道的主动接入,但可以被动的响应CTS报文并接收数据。位于多条多跳通信路径上的交叉节点需要更多的机会占用信道进行报文转发。对此,本文提出一种交叉节点标识机制,根据交叉节点需要转发的报文数量来确定该节点的动态等待时长。利用网络内通信流量在时间上的内在联系,本文根据节点周围竞争的历史信息对动态等待时长的计算进行平滑优化,进一步提高了协议的性能。模拟结果表明,DWMAC协议能够更加高效的处理MAC层竞争和冲突,主动和及时的调整节点的竞争行为,提高了无线自组网吞吐量和报文延迟方面的性能。
In recent years, with the in-depth research of related technologies and the improvement in hardware, there are more and more deployed wireless ad hoc networks in practice. A wireless ad hoc network is a network temporarily and spontaneously established by wireless communication nodes through distributed protocols, with the characteristics of infrastructureless, multihop, distributed and mobility. As one important part of the wireless ad hoc network protocol suite, the media access control (MAC) protocol determines how one wireless communication node transmits and receives packets through wireless channel. Thus, the MAC protocol largely determines the network performance which can be measured in terms of throughput, transmission delay and energy consumption, etc.
     Focus on how to improve the wireless ad hoc MAC protocol, this thesis first deeply analyses the essential factors which determine the performance of a MAC protocol. Then, this dissertation proposes and evaluates new solutions for concurrent transmission, intra-flow contention and inter-flow contention.
     The major contributions of this thesis include:
     1. Research on concurrent transmission mechanism. In a given area of the wireless ad hoc network, more scheduled transmissions means higher throughout. So, without violating each other, it is a promising approach to improve the throughput of a wireless ad hoc network MAC protocol by scheduling as more as possible transmissions in a given space. In wireless communication, a packet can be received successfully even if there exist other overlapping or interfering packets. This phenomenon is the so called capture effect. Based on the capture effect, this dissertation proposes a concurrent transmission MAC protocol (CTMAC), which can work on existing IEEE 802.11 hardware.
     CTMAC inserts additional control gap between the transmission of control packets (RTS/CTS/ATS) and DATA packet. After the successful exchange of control packets, a node waits until the finish of current additional control gap. Additionally, the control packets of CTMAC will not always silence the neighboring nodes. Thus, the additional control gap allows a series of RTS/CTS exchanges to take place between the nodes in the vicinity of the transmitting or receiving node to schedule possible multiple, concurrent data transmissions. To safeguard the concurrent data transmissions, collision avoidance information is included in the control packets and used by the neighboring nodes to determine whether they should begin their transmissions. Also, to isolate the possible interference between DATA packets and ACK packets, a novel ACK sequence mechanism is proposed. Because the size of additional control gap has a significant impact on the performance of the CTMAC, this thesis proposes a packet-level adaptive mechanism to adjust the length of additional control gap according to the number of concurrent transmissions in the vicinity. Simulation results show that a significant gain in throughput can be obtained by the CTMAC protocol compared with the existing work including the IEEE 802.11 MAC protocol.
     2. Research of intra-flow contention problem under multihop scenarios. Due to the characteristics of infrastructureless and multihop, most of the traffics in a wireless ad hoc network are multihop. To fulfill the forwarding of the received packets, the neighboring nodes on a multihop route will contend with each other inevitably. This is the so called intra-flow contention problem, which limits the performance of the MAC protocol. By analyzing the essential characteristics of a multihop traffic, this dissertation proposed a novel voluntary waiting MAC protocol (VWMAC) to solve this problem. Through voluntary waiting by wireless hosts according to the length of data packet transmitted and the distance between neighboring nodes on the multihop path, VWMAC uses a surprisingly simple strategy to achieve significant performance enhancement. This thesis gains the equation to compute the length of voluntary waiting time and validate its correctness through simulation. In addition, voluntary waiting of participating nodes present opportunity for these nodes to transit to sleep state to conserve scarce energy. Our simulation results show that VWMAC outperforms IEEE 802.11 and existing approaches in terms of throughput, transmission delay and energy efficiency.
     3. Research of mechanisms for dealing with the MAC layer contentions. At the MAC layer, a wireless communication node faces various kinds of contentions which include intra-flow contention and inter-flow contention. The MAC layer contentions and the resulting collisions have significant impact on the performance of a MAC protocol. Dealing with these problems quickly and actively is necessary for a desirable wireless ad hoc MAC protocol. In this thesis, a novel MAC protocol, dynamic waiting MAC (DWMAC), is proposed to manage the contending actions of a wireless node dynamically according to the contention level.
     In DWMAC, a node waits voluntarily after the successful transmission of a DATA packet. The duration of waiting is determined jointly by the contention level in the vicinity and the length of the contended transmissions. In the state of dynamic waiting, a node loses the right of transmitting, even if it has packet waiting in it’s transmit queue. However, it can receive passively from neighboring nodes when RTS packet is received.
     The cross node which is on the routes of multiple multihop traffics needs more consideration, because it requires more chances to forward the received packets. In this dissertation, a marking mechanism is proposed to assign the cross node higher priority during the contention for the shared channel. Because the flows in the wireless ad hoc network have some intrinsic relationship, DWMAC uses an ARMA Filter method to utilize the history information and improve the performance further. Compared with existing solutions, DWMAC deals with the MAC layer contentions more effectively. The simulation results show that DWMAC protocol is able to adjust the action of a wireless communication node timely and actively, resulting significant improvements in throughput and packet delay.
引文
[1] Charles E. Perkins, Ad Hoc Networking, 2001, Addison-Wesley, London; ISBN: 0-201-30976-9 8~23.
    [2] Aleksi Penttinen. Research on Ad Hoc Networking: Current Activity and Future Directions. http://citeseer.nj.nec.com/533517.html.
    [3] Andrew S T,计算机网络(第三版). 熊桂喜,王小虎译. 国防工业出版社,2000.
    [4] M. B. Pursley. Direct-Sequence Spread-Spectrum Communications for Multipath Channels. IEEE Trans. Microwave Theory and Practice, Vol. 50: 653-661. March, 2002.
    [5] Y. Dorfan. High-speed Data in EGPRS--A Physical Layer Challenge. RF Design Magazine, pp. 26-34, May 2002.
    [6] Chane L. Fullmer , J. J. Garcia-Luna-Aceves. Solutions to hidden terminal problems in wireless networks. ACM SIGCOMM Computer Communication Review, vol.27 (4):39-49, Oct. 1997.
    [7] Timothy J. Shepard. A channel access scheme for large dense packet radio networks. ACM SIGCOMM Computer Communication Review, vol.26(4):219-230, Oct. 1996.
    [8] X. Hong, K. Xu, and M. Gerla. Scalable Routing Protocols for Mobile Ad Hoc Networks. IEEE Network, 16(4):11-21, July-August 2000.
    [9] S. Lee, J. Hsu, R. Hayashida, et al. Selecting a Routing Strategy for Your Ad Hoc Network. Computer Communications, vol. 26:723-733, Oct. 2003.
    [10] H. Luo, S. Lu, and V. Bharghavan. A New Model for Packet Scheduling in Multihop Wireless Networks. In Proceedings of MobiCom'00, pp.76-86, 2000.
    [11] K. Xu, M. Gerla, L. Qi, and Y. Shu. Enhancing TCP fairness in ad hoc wireless networks using neighborhood RED. in Proceedings of the 9th International Conference on Mobile Computing and Networking (MOBICOM’03), pp. 16-28, Sept. 2003.
    [12] Abhinav Gupta, Ian Wormsbecker, and Carey Williamson. Experimental Evaluation of TCP Performance in Multi-hop Wireless Ad Hoc Networks. in Proceedings of IEEE/ACM MASCOTS, Volendam, Netherlands, pp. 3-11, Oct. 2004.
    [13] 王 波, 范平志. 基于无线自组织网络的 TCP Freeze-Probing 改进协议. 软件学报,Vol.16(5):878-885, 2005.
    [14] S. Kumar, V. S. Raghavan and J. Deng. Medium Access Control Protocols for Ad-Hoc Wireless Networks: A Survey. Elsevier Ad-Hoc Networks Journal, Vol.4(3):326-358, May 2006.
    [15] F. A. Tobagi, and L. Kleinrock. Packet switching in radio channels: Part II – the hidden terminal problem in carrier sense multiple-access modes and the busy-tone solution. IEEE Trans. on Communications, 23(12): 1417-1433, Dec. 1975.
    [16] K. Xu, and M. Gerla. TCP over an IEEE 802.11 Ad Hoc Network: Unfairness Problems and Solutions. Technical Report, Computer Science Department of UCLA, 2002.
    [17] A. Chandra, V. Gummalla, and J. O. Limb. Wireless Medium Access Control Protocols. IEEE Communications Surveys and Tutorials, Vol. 3, No. 2: 2-15, 2000.
    [18] R. Jurdak, C. V. Lopes, and P. Baldi. A Survey, Classification and Comparative Analysis of Medium Access Control Protocols for Ad Hoc Networks. IEEE Communications Surveys and Tutorials, Vol. 6, No. 1, 2004.
    [19] J. Yang, J. Li, M. Sheng. MAC Protocol for Mobile Ad Hoc Network with Smart Antennas. IEEE Electronics Letters, 39(6): 555-557, Mar. 2003.
    [20] Z. Huang, and C. Shen. A comparison study of omnidirectional and directional MAC protocols for ad hoc networks. in Proceedings of IEEE Global Telecommunications Conference (GLOBECOM'02), vol. 1, pp. 17-21, Nov. 2002.
    [21] N. Abramson. The ALOHA System-Another alternative for computer communications. In Proceedings of 1970 Fall Joint Comput. Conf., AFIPS Press, pp. 281-285, 1970.
    [22] L. Kleinrock, and F. A. Tobagi. Packet Switching in Radio Channels: Part I – Carrier Sense Multiple-access Modes and Their Throughput-delay Characteristics. IEEE Trans. on Communications, 23(12):1400-1416, Dec. 1975.
    [23] P. Karn. MACA—a new channel access method for packet radio. in Proceedings of the ARRL/CRRL Amateur Radio 9th Computer Networking Conference September 22, 1990.
    [24] V. Bhargavan, A. Demers, S. Shenker, L. Zhang. MACAW—A Media Access protocol for wireless Lans. in Proceedings of the ACM SIGCOMM 1994, pp. 212-225, 1994.
    [25] C.L. Fullmer, J.J. Garcia-Luna-Aceves. Floor Acquisition Multiple Access (FAMA) for packet-radio networks. in Proceedings of ACM SIGCOMM, Cambridge MA, August 28–September 1, 1995.
    [26] IEEE 802.11 Working Group, Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specification, 1997.
    [27] B. O_Hara, A. Petrick. IEEE 802.11 Handbook: A Designer’s Companion. IEEEPress, New York, 1999.
    [28] B.P. Crow, I. Widjaja, J.G. Kim, P.T. Sakai. IEEE 802.11 wireless local area networks. IEEE Commun. Mag, 1997.
    [29] S. Singh, C.S. Raghavendra. PAMAS—Power Aware Multi-Access protocol with Signaling for ad hoc networks. ACM Comput. Commun. Rev. 28 (3):5-26, 1998.
    [30] A. Chockalingam, M. Zorzi. Energy efficiency of media access protocols for mobile data networks. IEEE Trans. Commun. 46 (11) :1418-1421, 1998.
    [31] A.J. Goldsmith, S.B. Wicker. Design challenges for energy-constrained ad hoc wireless networks. IEEE Wireless Commun. 9 (4): 8-27, 2002.
    [32] E.-S. Jung, N.H. Vaidya. An energy efficient MAC protocol for wireless LANs. In Proceedings of the IEEE INFOCOM, June 2002.
    [33] H. Woesner, J.P. Ebert, M. Schlager, A. Wolisz. Power saving mechanisms in emerging standards for wireless LANs: the MAC level perspective. IEEE Person. Commun. 5 (3): 40-48, 1998.
    [34] Z. Fang et al. Performance Evaluation of a Fair Backoff Algorithm for IEEE 802.11 DFWMAC. In Proceedings of MobiHoc 2002, pp. 48-57, 2002.
    [35] K. Sundaresan, R. Sivakumar, M. A. Ingram, and T Chang. A Fair Medium Access Control Protocol for Ad Hoc Networks with MIMO Links. in Proceedings of INFOCOM'04, 2004..
    [36] T. Nandagopal, T. Kim, X. Gao, V. Bharghavan. Achieving MAC Layer Fairness in Wireless Packet Networks. in Proceedings of MobiCom'00, pp.298-309, 2000.
    [37] Z. Hadzi-Velkov and B. Spasenovski. Capture effect in IEEE 802.11 basic service area under influence of Rayleigh fading and near/far effect. in Proceedings of 13th IEEE Personal, Indoor and Mobile Radio Communications, vol. 1, Lisbon, Portugal, pp. 172-176, Sept. 2002.
    [38] J. H. Kim and J. K. Lee. Capture effects of wireless CSMA/CA protocols in Rayleigh and shadow fading channels. IEEE Trans. Veh. Technol., vol. 48(4):1277-1286, July 1999.
    [39] Yu Wang. Medium Access Control in Ad Hoc Networks with Omni-directional and Directional Antennas. PhD Thesis, Computer Engineering, University of California, Santa Cruz, CA 95064, June 2004.
    [40] J. J. Garcia-Luna-Aceves. Chane L. Fullmer. Floor acquisition multiple access (FAMA) in single-channel wireless networks. Mobile Networks and Applications, Vol. 4(3):157-174, October 1999.
    [41] F. Talucci, M. Gerla, and L. Fratta. MACA-BI (MACA By Invitation): A Receiver Oriented Access Protocol for Wireless Multi-hop Networks. In Proceedings of IEEE PIMRC’97, pp. 435-39, Sep. 1997.
    [42] A. Tzamaloukas. Sender- and Receiver-Initiated MAC Protocols for Ad-Hoc Networks. PhD Thesis, Computer Engineering, University of California, Santa Cruz, CA 95064, Dec. 2000.
    [43] J. Garcia-Luna-Aceves, and A. Tzamaloukas. Reversing the Collision-Avoidance Handshake in Wireless Networks. in Proceedings of ACM/IEEE Mobicom’99, pp. 120-131, Aug. 1999.
    [44] J. J. Garcia-Luna-Aceves, and A. Tzamaloukas. Receiver-initiated Collision Avoidance in Wireless Networks. ACM Wireless Networks, 8(2-3): 249-263, March 2002.
    [45] C. K. Toh, V. Vassiliou, G. Guichal, et al. MARCH: A Medium Access Control Protocol for Multihop Wireless Ad Hoc Networks. In Proceedings of IEEE Military Communication Conference (MILCOM’00), vol. 1, pp. 512-516, Oct. 2000.
    [46] L. Kleinrock, F.A. Tobagi. Packet switching in radio channels: Part I—carrier sense multiple access modes and their throughput-delay characteristics. IEEE Trans. commun. Vol(23) :1400-1416, Dec, 1975.
    [47] C. Wu, V.O.K. Li. Receiver-Initiated Busy-Tone Multiple Access in packet radio networks. In Proceedings of the ACM SIGCOMM Conference, pp. 336-342, 1987.
    [48] Z.J. Haas, J. Deng. Dual Busy Tone Multiple Access (DBTMA)—a multiple access control scheme for ad hoc networks. IEEE Trans. Commun. 50 (6): 975-984, 2002.
    [49] S. Singh, C.S. Raghavendra. PAMAS—Power Aware Multi-Access protocol with Signaling for ad hoc networks. ACM Comput. Commun. Rev. 28 (3): 5-26, 1998.
    [50] C.-H. Yeh, H. Zhou. A new class of collision-free MAC protocols for ad hoc wireless networks. In Proceedings of the Intertnational Conference on Advances in Infrastructure for e-Business, e-Education, e-science, and e-Medicine on the Internet, January 2002.
    [51] H. Zhai, J. Wang, and Y. Fang. DUCHA: A Dual-Channel MAC Protocol for Mobile Ad Hoc Networks. to appear in IEEE Transactions on Wireless Communications.
    [52] A. Nasipuri, J. Zhuang, S.R. Das. A multichannel CSMA MAC protocol for multihop wireless networks. In Proceedings of IEEE WCNC, pp.1402-1406, September, 1999.
    [53] J. So, N.H. Vaidya. A multi-channel MAC protocol for ad hoc wireless networks. Technical Report, CS Department of University of Illinois at Urbana-Champaign, January 2003.
    [54] A. Nasipuri, S.R. Das. Multichannel CSMA with signaling power-based channel selection for multihop wireless networks. In Proceedings of the IEEE VTC, September 2000.
    [55] S.L. Wu, C.Y. Lin, Y.C. Tseng, J.P. Sheu. A new multichannel MAC protocol with on-demand channel assignment for multi-hop mobile ad hoc networks. In Proceedings of the IEEE WCNC, Chicago, IL, September 2000.
    [56] S.L. Wu, Y.C. Tseng, C.Y. Lin, J.P. Sheu. A multi-channel MACprotocol with power control for multi-hop mobile ad hoc networks, Comput. J. (SCI) 45 (1):101–110, 2002.
    [57] N. Jain, S.R. Das. A. Nasipuri. A multichannel CSMA MAC protocol with receiver-based channel selection for multihop wireless networks. In Proceedings of the 9th International Conference Computer Communications and Networks (IC3N), October 2001.
    [58] R.R. Choudhury, X. Yang, R. Ramanathan, N.H. Vaidya. Using directional antennas for medium access control in ad hoc networks. In Proceedings of the ACM MOBICOM, pp.59-70, September 2002.
    [59] J. Zander. Slotted ALOHA multihop packet radio networks with directional antennas. Electron. Lett. 26 (25) :2098-2099, 1990.
    [60] C. Lau, C. Leung. A slotted ALOHA packet radio network with multiple antennas and receivers. IEEE Trans. Veh. Technol. 39 (3): 218-226, 1990.
    [61] T.S. Yum, K.W. Hung, Design algorithms for multihop packet radio networks with multiple directional antennas stations, IEEE Trans. Commun. 40 (11): 1716-1724, 1992.
    [62] R. Ramanathan. On the performance of ad hoc networks with beamforming antennas. In Proceedings of the ACM MOBIHOC, pp.95-105 October 2001.
    [63] Y.B. Ko, V. Shankarkumar. N.H. Vaidya, Medium Access Protocols using directional antennas in ad hoc networks. In Proceedings of the IEEE INFOCOM, March 2000.
    [64] A. Nasipuri, S. Ye, J. You, R. Hiromoto. A MAC protocol for mobile ad hoc networks using directional antennas. In Proceedings of the IEEE WCNC, September 2000.
    [65] Shugong Xu and Tarek Saadawi. Does the IEEE 802.11 MAC protocol work well in multihop wireless ad hoc networks. IEEE Communications Magazine, Vol. 39,No. 6: 130-137, June 2001.
    [66] IEEE 802.11e/D4.0, Draft Supplement to Part 11: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications: Medium Access Control (MAC) Enhancements for Quality of Service (QoS), November 2002.
    [67] Luciano Bononi, Luca Budriesi, Danilo Blasi, Vincenzo Cacace, Luca Casone,Salvatore Rotolo. A differentiated distributed coordination function MAC protocol for cluster-based wireless ad hoc networks. In Proceedings of the 1st ACM international workshop on performance evaluation of wireless ad hoc, sensor, and ubiquitous networks, pp. 77-86, 2004.
    [68] W.-P. Chen, et al. Dynamic clustering for acoustic target tracking in wireless sensor networks. IEEE Trans. on Mobile Computing, Special issue self-reconfiguring in sensor networks, vol. 3:258-271, 2004.
    [69] A. Banerjee and S. Khuller. A Clustering Scheme for Hierarchical Control in Multi-Hop Wireless Networks. In Proceedings of IEEE Infocom, 2002.
    [70] D. Blasi, V. Cacace, L. Casone and A. Losacco. Availability Clustering: a Spine-based Clustering Scheme to Exploit Nodes Heterogeneity in Ad Hoc Networks. In Proceedings of Med-Hoc-Net 2002, Mahdia, 2002.
    [71] I. Aad and C. Castelluccia. Differentiation mechanisms for IEEE 802.11. In Proceedings of INFOCOM, pp. 209-218, April 2001.
    [72] S.-T. Sheu and T.-F. Sheu. A bandwidth allocation/sharing/extension protocol for multimedia over IEEE 802.11 ad hoc wireless LANs . IEEE Journal on Selected Areas in Communications, 19(10):2065-2080, October 2001.
    [73] Y. Xiao. An Analysis for Differentiated Services in IEEE 802.11 and IEEE 802.11e Wireless LANs. In Proceedings of Int’l Conf. on Distributed Computing Systems, pp. 32-39, 2004.
    [74] Frikha, M, Najet, T, Tabbana, F. Mapping DiffServ to MAC differentiation for IEEE 802.11e. In Proceedings of Advanced International Conference on Telecommunications and International Conference on Internet and Web Applications and Services (AICT/ICIW 2006), 19-25, February 2006.
    [75] H. Wu, S. Cheng, Y. Peng, K. Long, and J. Ma. IEEE 802.11 distributed coordination function (DCF): analysis and enhancement. In Proceedings of IEEE Int. Conference on Communications (ICC), vol. 1, pp. 605-609, 2002.
    [76] Jing Deng, Pramod K. Varshney, Zygmunt J. Haas. A New Backoff Algorithm for the IEEE 802.11 Distributed Coordination Function. In Proceedings of Communication Networks and Distributed Systems Modeling and Simulation (CNDS '04), San Diego, CA, USA, January 18-21, 2004.
    [77] Manaseer,S. Ould-Khaoua,M. Mackenzie,L. Fibonacci Backoff Algorithm for Mobile Ad Hoc Networks. Tech Report of Dept of Computing Science, University of Glasgow. Number: TR-2006-212, 2006.
    [78] Finch, S. R. The Golden Mean Mathematical Constants. Cambridge University Press, pp. 5-12, 2003.
    [79] F. Cali, M. Conti, and E. Gregori. IEEE 802.11 Protocol: Design and Performance Evaluation of an Adaptive Backoff Mechanism. IEEE Journal On Selected Areas in Communications, Vol.18(9):1774-1786, September 2000.
    [80] W. T. Chen, B. J. Wang, Y. C. Lin, and Y. T. Chang. An Effective Contention Window Control Mechanism in 802.11 Wireless LAN. In Proceedings of the IASTED Conference on Wireless Networks and Emerging Technologies(WNET), July, 2005.
    [81] Kyle Jamieson, Bret Hull, Allen Miu, Hari Balakrishnan. Understanding the RealWorld Performance of Carrier Sense. SIGCOMM’05 Workshops, August 22–26, Philadelphia, PA, USA, 2005.
    [82] J. Zhu, X. Guo, LL Yang, and WS Conner. Leveraging spatial reuse in 802.11 mesh networks with enhanced physical carrier sensing. In Proceedings of IEEE ICC, 2004.
    [83] Jing Zhu, Xingang Guo, L. Lily Yang, W. Steven Conner, Sumit Roy, Mousumi M. Hazra. Adapting physical carrier sensing to maximize spatial reuse in 802.11 mesh networks. Wireless Communications and Mobile Computing, Vol 4(8):933-946, December 2004.
    [84] Jason A. Fuemmeler, Nitin H. Vaidya, Venugopal V. Veeravalli. Selecting Transmit Powers and Carrier Sense Thresholds for CSMA Protocols. Technical Report of University of Illinois at Urbana-Champaign. October, 2004.
    [85] Zhifei Li, Sukumar Nandi, Anil K. Gupta. ECS: An enhanced carrier sensing mechanism for wireless ad hoc networks. Elsevier Computer Communications 28(17): 1970-1984 ,2005.
    [86] X. Yang and N. H. Vaidya. On the physical carrier sense in wireless ad-hoc networks. In Proceedings of IEEE INFOCOM, 2005.
    [87] J. Deng , B. Liang, and P. K. Varshney. Tuning the Carrier Sensing Range of IEEE 802.11 MAC. In Proceedings of IEEE Globecom'04, 2004.
    [88] Zhifei Li, Sukumar Nandi, Anil K. Gupta. Improving MAC Performance in Wireless Ad Hoc Networks Using Enhanced Carrier Sensing (ECS). In Proceedings of NETWORKING 2004, pp.600-612, 2004.
    [89] S. Singh, C.S. Raghavendra, PAMAS-Power Aware Multi-Access protocol with Signaling for ad hoc networks, ACM Comput. Commun. Rev. 28 (3): 5-26, 1998.
    [90] E.-S. Jung and N. H. Vaidya. A Power Control MAC Protocol for Ad Hoc Networks. ACM/Kluwer Wireless Networks (WINET), Vol 11(1-2):55-66, 2005.
    [91] J. Monks, V. Bharghavan, W. Hwu. A Power Controlled Multiple Access protocol for wireless packet networks. in Proceedings of the IEEE INFOCOM, April 2001.
    [92] M. B. Pursley, H. B. Russell, and J. S. Wysocarski. Energy-efficient transmission and routing protocols for wireless multiple-hop networks and spread spectrum radios. In Proceedings of the EUROCOMM Conference, pp.1–5, 2000.
    [93] S.-L. Wu, Y.-C. Tseng, and J.-P. Sheu. Intelligent medium access for mobile ad hoc networks with busy tones and power control. IEEE Journal on SelectedAreas in Communications, 18(9):1647–1657, 2000.
    [94] A. Muqattash and M. Krunz. Power controlled dual channel (PCDC) medium access protocol for wireless ad hoc networks. In Proceedings of the IEEE INFOCOM Conference, pp. 470-480, 2003.
    [95] G. Bianchi. IEEE 802.11-saturation throughput analysis. IEEE Commun. Lett., vol. 2(12):318-320, Dec. 1998.
    [96] A. Acharya, A. Misra, and S. Bansal. MACA-P: a MAC for concurrent transmissions in multi-hop wireless networks. In Proceedings of the First IEEE PerCom 2003 Conference, pp. 505-508, Mar. 2003.
    [97] A Acharya, A Misra and S Bansal. Design and Analysis of a Cooperative Medium Access Scheme for Wireless Mesh Networks. In Proceedings of the First International Conference on Broadband Networks (BROADNETS’04), 2004.
    [98] Alaa Muqattash and Marwan Krunz. POWMAC: A Single-Channel Power- Control Protocol for Throughput Enhancement in Wireless Ad Hoc Networks. IEEE Journal on Selected Areas in Communications (JSAC), Vol. 23(5): 1067-1084, May 2005.
    [99] Data sheet: Cisco Aironet 350 Series client adapters. [Online]. Available: http://www.cisco.com/en/US/products/hw/wireless/index.htm.
    [100] V Kawadia and P.R.Kumar. Principles and protocols for power control in ad hoc networks. IEEE Journal on Selected Areas in Communications, Special Issue on Ad Hoc Networks, Vol 1:76-88, 2005.
    [101] T.Rappaport. Wireless Communications: Principles and Practice. Prentice Hall, 2002.
    [102] M. CESANA, D. Maniezzo, P. Bergamo, M. Gerla, Interference Aware (IA) MAC: an Enhancement to IEEE802.11b DCF. In proceedings of the IEEE Vehicular Technology Conference 2003, VTC fall 2003, pp. 2799-2803, October 2003.
    [103] Kay R?mer. Time Synchronization in Ad Hoc Networks. In Proceedings of MobiHoc 2001, ACM, October 2001.
    [104] Kay R?mer, Philipp Blum, and Lennart Meier. Time synchronization and calibration in wireless sensor networks. In Handbook of Sensor Networks: Algorithms and Architectures. John Wiley & Sons, September 2005.
    [105] T. S. Rappaport and L. B. Milstein. Effects of radio propagation path loss on DS-CDMA cellular frequency reuse efficiency for the reverse channel. IEEE Transactions on Vehicular Technology, Vol. 41:231–242, Aug. 1992.
    [106] http://pcl.cs.ucla.edu/projects/glomosim/
    [107] http://www.isi.edu/nsnam/ns/
    [108] http://www.opnet.com/opnet/home.html
    [109] http://www.scalable-networks.com/products/QualNet/
    [110] Arne Schmitz, Martin Wenig. The Effect of the Radio Wave Propagation Model in Mobile Ad Hoc Networks. In Proceedings of MSWiM’06, October, 2006.
    [111] T. S. Rappaport. Wireless communications, principles and practice. Prentice Hall, 1996.
    [112] Fu Z, Zerfos P, Luo H, Lu S, Zhang L, Gerla M. The Impact of multihop wireless channel on TCP throughput and loss. In Proceedings of the 22nd Annual Joint Conf. of the IEEE Computer and Communications Societies (INFOCOM 03), pp.1733-1753, 2003.
    [113] Zhenqiang Ye, Dan Berger, Prasun Sinha, et al. On Alleviating MAC Layer Self-Contention in Ad-hoc Networks. Poster, MobiCom, 2003.
    [114] H Zhai, X Chen and Y Fang. Alleviating intra-flow and inter-flow contentions for reliable service in mobile as hoc networks. In Proceedings of IEEE Military Communications Conference (Milcom'04), Monterey, California, Nov. 2004.
    [115] V. Kanodia, A. Sabharwal, and E. Knightly. MOAR: A Multi-channel Opportunistic Auto-rate Media Access Protocol for Ad Hoc Networks. in Proceedings of Broadnets 2004, San Jose, CA, October 2004.
    [116] Gavin Holland, Nitin Vaidya, Paramvir Bahl. A rate-adaptive MAC protocol for multi-Hop wireless networks. In Proceedings of the 7th annual international conference on Mobile computing and networking(MobiCom’01), pp.236-251, 2001.
    [117] Self Management in Chaotic Wireless Deployments, A. Akella, G. Judd, P. Steenkiste, and S. Seshan, ACM MobiCom, 2005.
    [118] http://www.ietf.org/internet-drafts/draft-ietf-manet-aodv-13.txt.
    [119] Yaling Yang and Robin Kravets. Contention-Aware Admission Control for Ad Hoc Networks. IEEE Transactions on Mobile Computing, Vol. 4(4):363-377, 2005.
    [120] Rong Zheng and Robin Kravets. On-demand Power Management for Ad Hoc Network [J].Elsevier Ad Hoc Journal, 2005.
    [121] F. Cali’, M. Conti, and E. Gregori. Dynamic Tuning of the IEEE 802.11 Protocol to Achieve a Theoretical Throughput Limit. IEEE/ ACM Trans. Networking, vol. 8(6):785-799, Dec. 2000.
    [122] Aravind Velayutham, Karthikeyan Sundaresan and Raghupathy Sivakumar. Non-pipelined Relay Improves Throughput Performance of Wireless Ad-hoc Networks. In proceeding of IEEE 24th Annual Joint Conference of the IEEE Computer and Communications Societies.(Infocom 2005), pp. 477-490, March 2005.
    [123] 詹姆斯.D.汉密尔顿.《时间序列分析》.刘明志译.中国社会科学出版社, 1999.
    [124] 何宏,李建东,盛敏,李维英. 基于 IEEE 802.11 协议的 EDCC 算法研究. 计算机学报, Vol. 28(1): 25 -34, 2005.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700