In wireless multimedia communications, it is extremely difficult to derive general end-to-end capacity results because of decentralized packet scheduling and the interference between communicating nodes. In this paper...In wireless multimedia communications, it is extremely difficult to derive general end-to-end capacity results because of decentralized packet scheduling and the interference between communicating nodes. In this paper, we present a state-based channel capacity perception scheme to provide statistical Quality-of-Service (QoS) guarantees under a medium or high traffic load for IEEE 802.11 wireless multi-hop networks. The proposed scheme first perceives the state of the wireless link from the MAC retransmission information and extends this information to calculate the wireless channel capacity, particularly under a saturated traffic load, on the basis of the interference among flows and the link state in the wireless multi-hop networks. Finally, the adaptive optimal control algorithm allocates a network resource and forwards the data packet by taking into consideration the channel capacity deployments in multi-terminal or multi-hop mesh networks. Extensive computer simulations demonstrate that the proposed scheme can achieve better performance in terms of packet delivery ratio and network throughput compared to the existing capacity prediction schemes.展开更多
Within the framework of its Statistical Capacity Building Program the African Development Bank （AfDB） is supporting development and improvement of statistical business registers （SBRs） in African countries. As a f...Within the framework of its Statistical Capacity Building Program the African Development Bank （AfDB） is supporting development and improvement of statistical business registers （SBRs） in African countries. As a first step, the AfDB prepared a document entitled Guidelines .for Building Statistical Business Registers in Africa, which describes SBR design, construction, introduction, use and maintenance. To support dissemination, interpretation and effective use of the Guidelines, the AfDB is now sponsoring a programme of review and recommendations for enhancements to SBRs in selected African national statistical offices. The paper outlines the content of the Guidelines and experiences in their application. The views expressed are those of the authors and ,do nnt nec＇e^arilv reflect an official nosition of the AfDB.展开更多
基金supported by the National Natural Science Foundation of China under Grants No.60972038,No.61001077,No.61101105 the Scientific Research Foundation for Nanjing University of Posts and Telecommunications under Grant No.NY211007+2 种基金 the Open Research Fund of National Mobile Communications Research Laboratory,Southeast University under Grant No.2011D05 Specialized Research Fund for the Doctoral Program of Higher Education under Grant No.20113223120002 University Natural Science Research Project of Jiangsu Province under Grant No.11KJB510016
文摘In wireless multimedia communications, it is extremely difficult to derive general end-to-end capacity results because of decentralized packet scheduling and the interference between communicating nodes. In this paper, we present a state-based channel capacity perception scheme to provide statistical Quality-of-Service (QoS) guarantees under a medium or high traffic load for IEEE 802.11 wireless multi-hop networks. The proposed scheme first perceives the state of the wireless link from the MAC retransmission information and extends this information to calculate the wireless channel capacity, particularly under a saturated traffic load, on the basis of the interference among flows and the link state in the wireless multi-hop networks. Finally, the adaptive optimal control algorithm allocates a network resource and forwards the data packet by taking into consideration the channel capacity deployments in multi-terminal or multi-hop mesh networks. Extensive computer simulations demonstrate that the proposed scheme can achieve better performance in terms of packet delivery ratio and network throughput compared to the existing capacity prediction schemes.
文摘Within the framework of its Statistical Capacity Building Program the African Development Bank （AfDB） is supporting development and improvement of statistical business registers （SBRs） in African countries. As a first step, the AfDB prepared a document entitled Guidelines .for Building Statistical Business Registers in Africa, which describes SBR design, construction, introduction, use and maintenance. To support dissemination, interpretation and effective use of the Guidelines, the AfDB is now sponsoring a programme of review and recommendations for enhancements to SBRs in selected African national statistical offices. The paper outlines the content of the Guidelines and experiences in their application. The views expressed are those of the authors and ,do nnt nec＇e^arilv reflect an official nosition of the AfDB.
