This paper proposed an optimized fast handoff scheme for real time applications in next generation IP based CDMA wireless networks. The idea is to utilize optimized IP multicasting handoff (based on PIM SM), which is ...This paper proposed an optimized fast handoff scheme for real time applications in next generation IP based CDMA wireless networks. The idea is to utilize optimized IP multicasting handoff (based on PIM SM), which is triggered by CDMA layer 2 functionality. An IP based cellular network model with WCDMA FDD air interface and IP based packet traffic is adopted. No special network entities and signaling for handoff are added in our network model. The simulation results show that low delay and low packet lost rate can be obtained.展开更多
A new traffic model for mobile wireless networks was given and analysed. In the model, it is considered of traffic characteristic for two special periods of time. A pre-emptive priority scheme combined with channel bo...A new traffic model for mobile wireless networks was given and analysed. In the model, it is considered of traffic characteristic for two special periods of time. A pre-emptive priority scheme combined with channel borrowing strategy according to the speciality was proposed. All the channels can be used by non-real-time services, and real-time services are given higher priority for they are allowed to pre-empt channels used by non-real-time services. Either real-time handoff requests or non-real-time handoff requests can be queued in queues when there is no channel can be used. Some channels are reserved for real-time handoff requests, which can also be used by non-real-time service when they are idle. Simulation results are also given. It is seen that our scheme performs better than other schemes when the arrival rate of real-time services is much higher than non-real-time services.展开更多
A new vertical handoff decision algorithm is proposed to maximize the system benefit in heterogeneous wireless networks which comprise cellular networks and wireless local area networks （WLANs）. Firstly the block pr...A new vertical handoff decision algorithm is proposed to maximize the system benefit in heterogeneous wireless networks which comprise cellular networks and wireless local area networks （WLANs）. Firstly the block probability, the drop probability and the number of users in the heterogeneous networks are calculated in the channel-guard call admission method, and a function of the system benefit which is based on the new call arrival rate and the handoff call arrival rate is proposed. Then the optimal radius of WLAN is obtained by using simulation annealing （SA） method to maximize the benefit. All the nodes should handoff from cellular network to WLAN if they enter WLAN＇s scope and handoff from WLAN to cellular network if they leave the scope. Finally, the algorithm in different new call arrival rates and handoff call arrival rates is analyzed and results show that it can achieve good effects.展开更多
The previous research on administration of the transmission capacity in the wired/ wireless ATM networks only focuses on wired part or wireless part. There are very few people do the work extending to the links associ...The previous research on administration of the transmission capacity in the wired/ wireless ATM networks only focuses on wired part or wireless part. There are very few people do the work extending to the links associating with handoff in the whole network. This paper develops the algorithms of transmission capacity administration on the link connecting the base station and base station controller (including the air interface of the base station) and the VPs among the base station controllers in the wired/ wireless ATM networks, which adapt to the traffic state of each service in every cellular cell to allocate (provision) transmission capacity and to reserve handoff guard capacity on these links, respectively. By simulating and analyzing the performance of the algorithm, it is found that it does well for the multimedia communication in which the transmission capacity requirement of each service may be widely different, so that the network bandwidth resource can be used efficiently.展开更多
针对异构环境下不同业务类型用户对于接入网络的不同服务质量(quality of service,Qo S)需求,该文提出了一种基于马尔可夫决策模型的切换选择算法.建立基于软件定义网络(software defined network,SDN)的异构无线网络架构,以实现对异构...针对异构环境下不同业务类型用户对于接入网络的不同服务质量(quality of service,Qo S)需求,该文提出了一种基于马尔可夫决策模型的切换选择算法.建立基于软件定义网络(software defined network,SDN)的异构无线网络架构,以实现对异构网络的通透控制.利用马尔可夫过程预测下一时刻的网络状态以得到采取动作后的一次回报,依据网络的不同状态属性针对实时用户和非实时用户分别构建立即回报函数,并采用层次分析法确定属性权重;基于状态动作对构建期望回报函数,采用逐次逼近的迭代方式得到使长期期望回报最大的切换策略.仿真结果表明,该方法针对不同业务类型用户均能选取最优切换策略,同时降低阻塞率,提高了用户的Qo S和无线网络的资源利用率.展开更多
文摘This paper proposed an optimized fast handoff scheme for real time applications in next generation IP based CDMA wireless networks. The idea is to utilize optimized IP multicasting handoff (based on PIM SM), which is triggered by CDMA layer 2 functionality. An IP based cellular network model with WCDMA FDD air interface and IP based packet traffic is adopted. No special network entities and signaling for handoff are added in our network model. The simulation results show that low delay and low packet lost rate can be obtained.
基金The National Natural Science Foundation of China (No60372076)
文摘A new traffic model for mobile wireless networks was given and analysed. In the model, it is considered of traffic characteristic for two special periods of time. A pre-emptive priority scheme combined with channel borrowing strategy according to the speciality was proposed. All the channels can be used by non-real-time services, and real-time services are given higher priority for they are allowed to pre-empt channels used by non-real-time services. Either real-time handoff requests or non-real-time handoff requests can be queued in queues when there is no channel can be used. Some channels are reserved for real-time handoff requests, which can also be used by non-real-time service when they are idle. Simulation results are also given. It is seen that our scheme performs better than other schemes when the arrival rate of real-time services is much higher than non-real-time services.
文摘A new vertical handoff decision algorithm is proposed to maximize the system benefit in heterogeneous wireless networks which comprise cellular networks and wireless local area networks （WLANs）. Firstly the block probability, the drop probability and the number of users in the heterogeneous networks are calculated in the channel-guard call admission method, and a function of the system benefit which is based on the new call arrival rate and the handoff call arrival rate is proposed. Then the optimal radius of WLAN is obtained by using simulation annealing （SA） method to maximize the benefit. All the nodes should handoff from cellular network to WLAN if they enter WLAN＇s scope and handoff from WLAN to cellular network if they leave the scope. Finally, the algorithm in different new call arrival rates and handoff call arrival rates is analyzed and results show that it can achieve good effects.
文摘The previous research on administration of the transmission capacity in the wired/ wireless ATM networks only focuses on wired part or wireless part. There are very few people do the work extending to the links associating with handoff in the whole network. This paper develops the algorithms of transmission capacity administration on the link connecting the base station and base station controller (including the air interface of the base station) and the VPs among the base station controllers in the wired/ wireless ATM networks, which adapt to the traffic state of each service in every cellular cell to allocate (provision) transmission capacity and to reserve handoff guard capacity on these links, respectively. By simulating and analyzing the performance of the algorithm, it is found that it does well for the multimedia communication in which the transmission capacity requirement of each service may be widely different, so that the network bandwidth resource can be used efficiently.
文摘针对异构环境下不同业务类型用户对于接入网络的不同服务质量(quality of service,Qo S)需求,该文提出了一种基于马尔可夫决策模型的切换选择算法.建立基于软件定义网络(software defined network,SDN)的异构无线网络架构,以实现对异构网络的通透控制.利用马尔可夫过程预测下一时刻的网络状态以得到采取动作后的一次回报,依据网络的不同状态属性针对实时用户和非实时用户分别构建立即回报函数,并采用层次分析法确定属性权重;基于状态动作对构建期望回报函数,采用逐次逼近的迭代方式得到使长期期望回报最大的切换策略.仿真结果表明,该方法针对不同业务类型用户均能选取最优切换策略,同时降低阻塞率,提高了用户的Qo S和无线网络的资源利用率.
