1 IntroductionWith the rapid development of backbonenetworks,the subscriber accessnetwork,a major component of publictelecom network equipment and so-called the“last kilometer”,has turned out to bethe focus of atten...1 IntroductionWith the rapid development of backbonenetworks,the subscriber accessnetwork,a major component of publictelecom network equipment and so-called the“last kilometer”,has turned out to bethe focus of attention.Among various access technologies,thebroadband wireless access system featuresquick network construction,rapid investmentreturn and large bandwidth.It enables newnetwork operators to provide services quickly展开更多
Broadband Wireless Access (BWA) has become one of the major evolution trends in the fields of broadband access and mobile communications. However,some difficulties emerged during the application and industrialization ...Broadband Wireless Access (BWA) has become one of the major evolution trends in the fields of broadband access and mobile communications. However,some difficulties emerged during the application and industrialization of the BWA system,which calls for typical service models,key technology innovations and backbone support from broadband Internet. This article introduces a Broadband Wireless Multimedia (BWM) access system. It aims to build a new-type "triple play" BWA network by integrating terrestrial digital TV system and the BWA system,and by taking broadband Internet as its core network platform. A primary research shows that the new BWA system is an effective solution to the existing difficulties of BWA system. Moreover,it is quite competitive in service provision,service coverage,frequency planning,terminal power consumption and cost for network construction.展开更多
It is wise for fixed operators to make use of broadband wireless access technologies,such as IEEE802.16d,to develop mobile access based on their existing fixed broadband IP networks.Mobile operators have to evolve the...It is wise for fixed operators to make use of broadband wireless access technologies,such as IEEE802.16d,to develop mobile access based on their existing fixed broadband IP networks.Mobile operators have to evolve their networks from 2G to 3G for making full use of their current resources. However,the AII-IP core network will be a general trend since broadband wireless access adopts the connectionless statistical packet multiplexing technology.Based on the introduction of IEEE802.16d,High Speed Downlink Packet Access (HSDPA) and CDMA2000 1x EV-DV technologies,this paper discusses the development trend of broadband wireless access technologies, and concludes that 3G's packet access technologies are the same as IEEE802.16d/e,and AII-IP is the goal.It emphasizes that Chinese TD-SCDMA should develop toward connectionless statistical packet multiplexing as early as possible.展开更多
The MAC layer in IEEE802.16 is designed to differentiate service among traffic categories with different multimedia requirements.In this paper,a scheduling algorithm at MAC layer for multiple connections with diverse ...The MAC layer in IEEE802.16 is designed to differentiate service among traffic categories with different multimedia requirements.In this paper,a scheduling algorithm at MAC layer for multiple connections with diverse QoS requirements is proposed.As for this algorithm,each connection is assigned a priority,which is updated dynamically based on its service status concluding queue characteristic and channel state.A connection with the highest priority is scheduled each time.Analytical model is developed by assuming a Finite State Markov Chain(FSMC)channel model.Simulation results show that the proposed scheduling algorithm can improve the performance of mean waiting time and throughput in broadband wireless networks.展开更多
文摘1 IntroductionWith the rapid development of backbonenetworks,the subscriber accessnetwork,a major component of publictelecom network equipment and so-called the“last kilometer”,has turned out to bethe focus of attention.Among various access technologies,thebroadband wireless access system featuresquick network construction,rapid investmentreturn and large bandwidth.It enables newnetwork operators to provide services quickly
文摘Broadband Wireless Access (BWA) has become one of the major evolution trends in the fields of broadband access and mobile communications. However,some difficulties emerged during the application and industrialization of the BWA system,which calls for typical service models,key technology innovations and backbone support from broadband Internet. This article introduces a Broadband Wireless Multimedia (BWM) access system. It aims to build a new-type "triple play" BWA network by integrating terrestrial digital TV system and the BWA system,and by taking broadband Internet as its core network platform. A primary research shows that the new BWA system is an effective solution to the existing difficulties of BWA system. Moreover,it is quite competitive in service provision,service coverage,frequency planning,terminal power consumption and cost for network construction.
文摘It is wise for fixed operators to make use of broadband wireless access technologies,such as IEEE802.16d,to develop mobile access based on their existing fixed broadband IP networks.Mobile operators have to evolve their networks from 2G to 3G for making full use of their current resources. However,the AII-IP core network will be a general trend since broadband wireless access adopts the connectionless statistical packet multiplexing technology.Based on the introduction of IEEE802.16d,High Speed Downlink Packet Access (HSDPA) and CDMA2000 1x EV-DV technologies,this paper discusses the development trend of broadband wireless access technologies, and concludes that 3G's packet access technologies are the same as IEEE802.16d/e,and AII-IP is the goal.It emphasizes that Chinese TD-SCDMA should develop toward connectionless statistical packet multiplexing as early as possible.
文摘The MAC layer in IEEE802.16 is designed to differentiate service among traffic categories with different multimedia requirements.In this paper,a scheduling algorithm at MAC layer for multiple connections with diverse QoS requirements is proposed.As for this algorithm,each connection is assigned a priority,which is updated dynamically based on its service status concluding queue characteristic and channel state.A connection with the highest priority is scheduled each time.Analytical model is developed by assuming a Finite State Markov Chain(FSMC)channel model.Simulation results show that the proposed scheduling algorithm can improve the performance of mean waiting time and throughput in broadband wireless networks.
文摘为了实现同一地域范围内的众多用户在有限带宽条件下提出的高QoS要求,本文对基于IEEE 802.16标准的宽带无线接入网中数据包级QoS(Quality of Service)性能进行了研究.具体做法是,首先采用批马尔可夫到达过程(BMAP,Batch Markov Arrival Process)和连续时间马尔科夫链(CTMC,Continuous Time Markov Chain)对到达过程和流量源进行建模,得到更符合实际和更准确的排队模型;然后基于状态空间,对一个无线接入网络系统进行建模,通过对得到的系统模型并结合前面得到的排队模型的深入分析,从而获得该模型下的各项QoS性能指标,如平均队列长度、丢包率、队列吞吐量和平均包时延.仿真实验结果表明,本文提出的算法模型相比于其他典型的算法模型,能够使得各项QoS性能指标有较大的改善和提高.