... Scheduling Long Bao Le and Ekram Hossain University of Manitoba, Winnipeg, MB, Canada. ... Bo... more ... Scheduling Long Bao Le and Ekram Hossain University of Manitoba, Winnipeg, MB, Canada. ... Both cases of with and without power control are considered. The achievable throughput for the round robin (RR), opportunistic and PF scheduling are evaluated and compared. ...
IEEE International Conference on Communications, 2005. ICC 2005. 2005
Abstract We analyze the radio link level queueing performance for a multi-rate wireless network ... more Abstract We analyze the radio link level queueing performance for a multi-rate wireless network using adaptive modulation and coding (AMC), scheduling, and automatic repeat request (ARQ)-based er-ror control. The analytical framework, which is developed based on a ...
AbstractWe analyze the radio link level buffer occupancy and delay statistics in a wireless netw... more AbstractWe analyze the radio link level buffer occupancy and delay statistics in a wireless network using adaptive modulation and coding (AMC), weighted round-robin scheduling and automatic repeat request (ARQ)-based error control. The queueing problems for two ...
Proceedings of the 3rd international conference on Quality of service in heterogeneous wired/wireless networks - QShine '06, 2006
A complete queueing model for radio link layer performance analysis is developed assuming adaptiv... more A complete queueing model for radio link layer performance analysis is developed assuming adaptive modulation and coding (AMC) at the physical layer and truncated automatic repeat request (ARQ)-based error control at the link layer. From the analysis the queue length distribution and the average queueing delay can be calculated. The average queueing delay is then used to estimate TCP (Transmission
2008 IEEE Wireless Communications and Networking Conference, 2008
In a cognitive wireless network, the licensed users (i.e., primary users) can sell redundant spec... more In a cognitive wireless network, the licensed users (i.e., primary users) can sell redundant spectrum to unlicensed users (i.e., secondary users) or secondary service providers. We consider a scenario where routers in the secondary users' network form a wireless infrastructure mesh network, which is overlaid on networks of several primary service providers, to relay the secondary users' traffic through multiple hops to the destination. For such a cognitive wireless mesh network, we investigate two levels of competitions. The first level of competition is among the primary users (or primary service providers) to choose the price for spectrum opportunities to maximize their revenues. The second level of competition is among the secondary users for spectrum usage to choose the source rate to maximize their utilities. Assuming that both primary and secondary users are selfish and they both wish to optimize their self-interest, we show how to use noncooperative games to formulate each of these competitions. Nash equilibrium is considered as the solution for both competitions. Performance evaluation of the proposed spectrum sharing and pricing framework for cognitive wireless mesh networks is carried out which shows several interesting aspects of the problem.
2012 IEEE International Conference on Communications (ICC), 2012
ABSTRACT In this paper, we consider the admission control problem for hybrid access in OFDMA-base... more ABSTRACT In this paper, we consider the admission control problem for hybrid access in OFDMA-based femtocell networks. We assume that Macrocell User Equipments (MUEs) can establish connections with Femtocell Base Stations (FBSs) to improve their QoSs. Both MUEs and Femtocell User Equipments (FUEs) have minimum rate requirements, which depend on their geographical locations and maybe their running applications. In addition, blocking probability constraints are imposed on each FUE so that connections from MUEs only result in controllable performance degradation for FUEs. We show how to formulate the admission control problem as a Semi-Markov Decision Process (SMDP) and present a Linear Programming (LP) based solution approach. Moreover, we develop a novel femtocell power adaptation algorithm, which can be implemented in a distributed manner jointly with the proposed admission control scheme. This power adaptation algorithm enables to achieve better cell throughput and more energy-efficient operation of the femtocell network considering the heterogeneity of traffic load in the network. Finally, numerical results are presented to illustrate the desirable performance of the optimal admission control solution and the significant throughput and power saving gains of the proposed cross-layer solution.
... We observe that channel correlation negatively impacts the TCP throughput performance. Also, ... more ... We observe that channel correlation negatively impacts the TCP throughput performance. Also, throughput enhancement of TCP NewReno over TCP Reno is observed to be non-negligible only if no ARQ-based error recovery is employed at the link layer. 1 Introduction ...
IEEE Transactions on Wireless Communications, 2012
We study the robust transmission scheduling and power control problem for spectrum sharing betwee... more We study the robust transmission scheduling and power control problem for spectrum sharing between secondary and primary users in a spatial reuse time-division multiple access (STDMA) network. The objective is to find a robust minimum-length schedule for secondary users (in terms of time slots) subject to the interference constraints for primary users and the traffic demand of secondary users. We
... Scheduling Long Bao Le and Ekram Hossain University of Manitoba, Winnipeg, MB, Canada. ... Bo... more ... Scheduling Long Bao Le and Ekram Hossain University of Manitoba, Winnipeg, MB, Canada. ... Both cases of with and without power control are considered. The achievable throughput for the round robin (RR), opportunistic and PF scheduling are evaluated and compared. ...
IEEE International Conference on Communications, 2005. ICC 2005. 2005
Abstract We analyze the radio link level queueing performance for a multi-rate wireless network ... more Abstract We analyze the radio link level queueing performance for a multi-rate wireless network using adaptive modulation and coding (AMC), scheduling, and automatic repeat request (ARQ)-based er-ror control. The analytical framework, which is developed based on a ...
AbstractWe analyze the radio link level buffer occupancy and delay statistics in a wireless netw... more AbstractWe analyze the radio link level buffer occupancy and delay statistics in a wireless network using adaptive modulation and coding (AMC), weighted round-robin scheduling and automatic repeat request (ARQ)-based error control. The queueing problems for two ...
Proceedings of the 3rd international conference on Quality of service in heterogeneous wired/wireless networks - QShine '06, 2006
A complete queueing model for radio link layer performance analysis is developed assuming adaptiv... more A complete queueing model for radio link layer performance analysis is developed assuming adaptive modulation and coding (AMC) at the physical layer and truncated automatic repeat request (ARQ)-based error control at the link layer. From the analysis the queue length distribution and the average queueing delay can be calculated. The average queueing delay is then used to estimate TCP (Transmission
2008 IEEE Wireless Communications and Networking Conference, 2008
In a cognitive wireless network, the licensed users (i.e., primary users) can sell redundant spec... more In a cognitive wireless network, the licensed users (i.e., primary users) can sell redundant spectrum to unlicensed users (i.e., secondary users) or secondary service providers. We consider a scenario where routers in the secondary users' network form a wireless infrastructure mesh network, which is overlaid on networks of several primary service providers, to relay the secondary users' traffic through multiple hops to the destination. For such a cognitive wireless mesh network, we investigate two levels of competitions. The first level of competition is among the primary users (or primary service providers) to choose the price for spectrum opportunities to maximize their revenues. The second level of competition is among the secondary users for spectrum usage to choose the source rate to maximize their utilities. Assuming that both primary and secondary users are selfish and they both wish to optimize their self-interest, we show how to use noncooperative games to formulate each of these competitions. Nash equilibrium is considered as the solution for both competitions. Performance evaluation of the proposed spectrum sharing and pricing framework for cognitive wireless mesh networks is carried out which shows several interesting aspects of the problem.
2012 IEEE International Conference on Communications (ICC), 2012
ABSTRACT In this paper, we consider the admission control problem for hybrid access in OFDMA-base... more ABSTRACT In this paper, we consider the admission control problem for hybrid access in OFDMA-based femtocell networks. We assume that Macrocell User Equipments (MUEs) can establish connections with Femtocell Base Stations (FBSs) to improve their QoSs. Both MUEs and Femtocell User Equipments (FUEs) have minimum rate requirements, which depend on their geographical locations and maybe their running applications. In addition, blocking probability constraints are imposed on each FUE so that connections from MUEs only result in controllable performance degradation for FUEs. We show how to formulate the admission control problem as a Semi-Markov Decision Process (SMDP) and present a Linear Programming (LP) based solution approach. Moreover, we develop a novel femtocell power adaptation algorithm, which can be implemented in a distributed manner jointly with the proposed admission control scheme. This power adaptation algorithm enables to achieve better cell throughput and more energy-efficient operation of the femtocell network considering the heterogeneity of traffic load in the network. Finally, numerical results are presented to illustrate the desirable performance of the optimal admission control solution and the significant throughput and power saving gains of the proposed cross-layer solution.
... We observe that channel correlation negatively impacts the TCP throughput performance. Also, ... more ... We observe that channel correlation negatively impacts the TCP throughput performance. Also, throughput enhancement of TCP NewReno over TCP Reno is observed to be non-negligible only if no ARQ-based error recovery is employed at the link layer. 1 Introduction ...
IEEE Transactions on Wireless Communications, 2012
We study the robust transmission scheduling and power control problem for spectrum sharing betwee... more We study the robust transmission scheduling and power control problem for spectrum sharing between secondary and primary users in a spatial reuse time-division multiple access (STDMA) network. The objective is to find a robust minimum-length schedule for secondary users (in terms of time slots) subject to the interference constraints for primary users and the traffic demand of secondary users. We
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