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Efficient power control via pricing in wireless data networks
 IEEE Transactions on Communication
, 2000
"... A major challenge in operation of wireless communications systems is the efficient use of radio resources. One important component of radio resource management is power control, which has been studied extensively in the context of voice communications. With increasing demand for wireless data servic ..."
Abstract

Cited by 201 (6 self)
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A major challenge in operation of wireless communications systems is the efficient use of radio resources. One important component of radio resource management is power control, which has been studied extensively in the context of voice communications. With increasing demand for wireless data services, it is necessary to establish power control algorithms for information sources other than voice. We present a power control solution for wireless data in the analytical setting of a game theoretic framework. In this context, the quality of service (QoS) a wireless terminal receives is referred to as the utility and distributed power control is a noncooperative power control game where users maximize their utility. The outcome of the game results in a Nash equilibrium that is ine#cient. We introduce pricing of transmit powers in order to obtain Pareto improvement of the noncooperative power control game, i.e. to obtain improvements in user utilities relative to the case with no pricing. Specifically, we consider a pricing function that is a linear function of the transmit power. The simplicity of the pricing function allows a distributed implementation where the price can be broadcast by the base station to all the terminals. We see that pricing is especially helpful in a heavily loaded system.
Downlink Power Allocation for Multiclass CDMA Wireless Networks
, 2002
"... In this paper we consider the downlink power allocation problem for multiclass CDMA wireless networks. We use a utility based power allocation framework to treat multiclass services in a unified way. The goal of this paper is to obtain a power allocation which maximizes the total system utility. I ..."
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Cited by 48 (4 self)
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In this paper we consider the downlink power allocation problem for multiclass CDMA wireless networks. We use a utility based power allocation framework to treat multiclass services in a unified way. The goal of this paper is to obtain a power allocation which maximizes the total system utility. In the wireless context, natural utility functions for each mobile are nonconcave. Hence, we cannot use existing techniques on convex optimization problems to derive a social optimal solution. We propose a simple distributed algorithm to obtain an approximation to the social optimal power allocation. The proposed distributed algorithm is based on dynamic pricing and allows partial cooperation between mobiles and the base station. The algorithm consists of two stages. At the mobile selection stage, the base station selects mobiles to which power is allocated, considering the partialcooperative nature of mobiles. This is called partialcooperative optimal selection, since in a partialcooperative setting and pricing scheme considered in this paper, this selection is optimal and satisfies system feasibility. At the power allocation stage, the base station allocates power to the selected mobiles. This power allocation is a social optimal power allocation among mobiles in the partialcooperative optimal selection, thus, we call it a partialcooperative optimal power allocation. We compare the partialcooperative optimal power allocation with the social optimal power allocation for the single class case. From these results, we infer that the system utility obtained by the partialcooperative optimal power allocation is quite close to the system utility obtained by the social optimal allocation.
Joint Resource Allocation and BaseStation Assignment for the Downlink in CDMA Networks
"... In this paper, we consider the joint resource allocation and basestation assignment problem for the downlink in CDMA networks with heterogeneous data services. We first study a power and rate control problem that attempts to maximize the expected throughput of the system. This problem is inherent ..."
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Cited by 5 (0 self)
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In this paper, we consider the joint resource allocation and basestation assignment problem for the downlink in CDMA networks with heterogeneous data services. We first study a power and rate control problem that attempts to maximize the expected throughput of the system. This problem is inherently difficult because it is in fact a nonconvex optimization problem. To solve this problem, we propose a distributed algorithm based on dynamic pricing.
Analyzing Wireless Networks
, 2000
"... In recent years, the number and variety of wireless network installations have dramatically increased, from smallscale installations spanning buildings and campuses to much largerscale installations spanning cities and metropolitan areas. As these wireless networks proliferate, the population of u ..."
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Cited by 2 (1 self)
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In recent years, the number and variety of wireless network installations have dramatically increased, from smallscale installations spanning buildings and campuses to much largerscale installations spanning cities and metropolitan areas. As these wireless networks proliferate, the population of users taking advantage of these networks for communication and access to online services and information also increases. To aid this growing population of users, many research and development efforts focus on upgrading and enhancing the services provided to the users. As part of these efforts, it is crucial to analyze real wireless networks to understand better how users take advantage of them. These analyses are important for at least two reasons. First, they are helpful for creating more realistic models of users when simulating new services, which is a common technique used in the mobile networking community to predict performance. Second, they are also helpful in focusing research on topics that will impact users the most. This thesis analyzes two very different wireless networks: the Metricom Ricochet packet radio network, a high latency, low bandwidth, metropolitanarea wireless network, and the WaveLAN network installed in the Gates Computer Science Building, a low latency, high bandwidth, localarea network. These analyses answer questions about network utilization, traffic characteristics, and user mobility rates and patterns. Among other results, we find that traffic peaks are usually caused by a single user rather than multiple users, and that significantly asymmetric network throughput would be undesirable for the WaveLAN network users. We also determine that users can indeed be categorized based on their mobility in the Metricom analysis and based on their usage ...
Orthogonal polynomials associated with root systems,Preprint(1988
 the IEEE Journal on Selected Areas in Communications
, 2006
"... Recent research in wireless CDMA systems has shown that adaptive rate/power control can considerably increase network throughput relative to systems that use only power or rate control. In this paper, we consider joint power/rate optimization in the context of orthogonal modulation (OM) and investig ..."
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Cited by 1 (0 self)
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Recent research in wireless CDMA systems has shown that adaptive rate/power control can considerably increase network throughput relative to systems that use only power or rate control. In this paper, we consider joint power/rate optimization in the context of orthogonal modulation (OM) and investigate the additional performance gains achieved through adaptation of the OM order. We show that such adaptation can significantly increase network throughput while simultaneously reducing the perbit energy consumption relative to fixedorder modulation systems. The optimization is carried out under two different objective functions: minimizing the maximum service time and maximizing the sum of user rates. For the first objective function, we prove that the optimization problem can be formulated as a generalized geometric program (GGP). We then show how this GGP can be transformed into a nonlinear convex program, which can be solved optimally and efficiently. For the second objective function, we obtain a lower bound on the performance gain of adaptive OM (AOM) over fixedmodulation systems. Numerical results indicate that relative to an optimal joint rate/power control fixedorder modulation scheme, the proposed AOM scheme achieves significant throughput and energy gains. I.
Downlink Power Allocation for Multiclass CDMA
"... In this paper we consider the downlink power allocation problem for multiclass CDMA wireless networks. We use a utility based power allocation framework to treat multiclass services in a unified way. The goal of this paper is to obtain a power allocation which maximizes the total system utility. I ..."
Abstract
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In this paper we consider the downlink power allocation problem for multiclass CDMA wireless networks. We use a utility based power allocation framework to treat multiclass services in a unified way. The goal of this paper is to obtain a power allocation which maximizes the total system utility. In the wireless context, natural utility functions for each mobile are nonconcave. Hence, we cannot use existing techniques on convex optimization problems to derive a social optimal solution. We propose a simple distributed algorithm to obtain an approximation to the social optimal power allocation. The proposed distributed algorithm is based on dynamic pricing and allows partial cooperation between mobiles and the base station. The algorithm consists of two stages. At the mobile selection stage, the base station selects mobiles to which power is allocated, considering the partialcooperative nature of mobiles. This is called partialcooperative optimal selection, since in a partialcooperative setting and pricing scheme considered in this paper, this selection is optimal and satisfies system feasibility. At the power allocation stage, the base station allocates power to the selected mobiles. This power allocation is a social optimal power allocation among mobiles in the partialcooperative optimal selection, thus, we call it a partialcooperative optimal power allocation. We compare the partialcooperative optimal power allocation with the social optimal power allocation for the single class case. From these results, we infer that the system utility obtained by the partialcooperative optimal power allocation is quite close to the system utility obtained by the social optimal allocation.
A Framework for Performance Evaluation and Optimization of an Emerging Multimedia DSCDMA Network
, 2000
"... This paper proposes a framework for performance evaluation and optimization of an emerging multimedia, packet DirectSequence Code Division Multiple Access (DSCDMA) network with a wide range of Quality of Service (QoS) requirements on losses and delays. The need for a new framework arises from inab ..."
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This paper proposes a framework for performance evaluation and optimization of an emerging multimedia, packet DirectSequence Code Division Multiple Access (DSCDMA) network with a wide range of Quality of Service (QoS) requirements on losses and delays. The need for a new framework arises from inability of the traditional approach, based on the outage probability, to capture the queueing aspects of DSCDMA network behavior in presence of delay tolerant traffic. Accounting for these aspects becomes essential for emerging multimedia DSCDMA networks attempting to approach their capacity limits by using coding and spreading gain control, retransmissions, as well as transmission scheduling/power control. Since in a DSCDMA network transmissions compete for simultaneous access to several resources, including wireless bandwidth and transmission power, the paper proposes to approximate the feasible QoS region for the network by the intersection of the feasible QoS regions for the corresponding singleresource systems. The feasible QoS region for a singleresource system is estimated by using M/G/1 conservation laws. Based on this "bottleneck resource" approximation, the paper estimates the admission region for the network and outlines the approach to the network management aimed at maximizing the admission region.
doi:10.1155/2007/76193 Research Article A UtilityBased Downlink Radio Resource Allocation for Multiservice Cellular DSCDMA Networks
, 2007
"... A novel framework is proposed to model downlink resource allocation problem in multiservice directsequence code division multipleaccess (DSCDMA) cellular networks. This framework is based on a defined utility function, which leads to utilizing the network resources in a more efficient way. This u ..."
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A novel framework is proposed to model downlink resource allocation problem in multiservice directsequence code division multipleaccess (DSCDMA) cellular networks. This framework is based on a defined utility function, which leads to utilizing the network resources in a more efficient way. This utility function quantifies the degree of utilization of resources. As a matter of fact, using the defined utility function, users ’ channel fluctuations and their delay constraints along with the load conditions of all BSs are all taken into consideration. Unlike previous works, we solve the problem with the general objective of maximizing the total network utility instead of maximizing the achieved utility of each base station (BS). It is shown that this problem is equivalent to finding the optimum BS assignment throughout the network, which is mapped to a multidimensional multiplechoice knapsack problem (MMKP). Since MMKP is NPhard, a polynomialtime suboptimal algorithm is then proposed to develop an efficient basestation assignment. Simulation results indicate a significant performance improvement in terms of achieved utility and packet drop ratio. Copyright © 2007 Mahdi Shabany et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1.
Resource Management in CDMAbased Satellite Networks
, 2004
"... There is interest, supported by successful field trials, in the use of satellite communications at the Ka band (30/20 GHz) and beyond to meet emerging demand for broadband interactive multimedia services. The key advantages of operation at Ka band are availability of bandwidth and favorable implicat ..."
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There is interest, supported by successful field trials, in the use of satellite communications at the Ka band (30/20 GHz) and beyond to meet emerging demand for broadband interactive multimedia services. The key advantages of operation at Ka band are availability of bandwidth and favorable implications for terminal size, cost and mobility. We study two problems related to bandwidth management of the uplink in a multibeam, CDMAbased, GEO satellite. Our focus is on the delivery of data services with rigid constraints on biterror rate and elastic constraints on data rate. The first of the two problems concerns the design of the coverage areas of the satellite beams. We were interested specifically in the adaptation of beam shape to inhomogeneity in the geographic distribution of the user population, and in the impact of beam shaping on the set of transmission rates that are compatible with prescribed constraints on transmission powers and signaltointerference ratios. Assuming that the spatial distribution of users is known, we construct an algorithm which computes beam coverage regions to equilibrate the perbeam user populations. The impact on the set of feasible bitrate allocations is