Radio resource allocation problems for OFDMA cellular systems

Abrardo, Andrea; Alessio, Alessandro; Detti, Paolo; Moretti, Marco

doi:10.1016/j.cor.2008.02.018

Cited by 29 publications

(32 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although some special cases do have clean polynomial time solutions (e.g. [6] deals with Min-MA under the assumption that only one transmission format is available to all users) they are not optimal for the general case because of the restrictions imposed. In addition, all heuristics which aim to solve the general case of Min-MA, MinMax-MA, Max-RA, and MaxMin-RA have been verified by simulation only, and none of them has a provable performance bound.…”

Section: Related Workmentioning

confidence: 99%

“…By assuming that every subcarrier allocated to the same user is loaded with same amount of bit, the first heuristic uses integer relaxation technique to transform the original ILP to a LP, and the other one is an application of Vogel's method [13]. Abrardo et al [6] study both single and multi cells versions of the margin adaptive problem. By assuming that only one transmission format is available to all users, Alen et al [14] devise a distributed algorithm aims to maximize system capacity.…”

Section: Related Workmentioning

confidence: 99%

“…This is a combinatorial resource allocation problem: in each time-slot, given m users, n sub-carriers and complete channel knowledge, how to assign disjoint sets of subcarriers to each user so as to optimize some system objective. The allocation problem has received active interest in the research community and has been studied from two perspectives: schemes that seek to minimize the amount of transmit power (known as Margin-Adaptive (MA) approaches [3] [4][5] [6]) and those that seek to maximize throughput (known as Rate-Adaptive (RA) approaches [7][8] [5]). Although optimal/near-optimal solutions for single user OFDM that use water-filling [9] are well known, optimal resource allocation in multiuser OFDM is still under-explored.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Subcarrier Allocation in Multiuser OFDM Systems: Complexity and Approximability

Huang

Gai

Krishnamachari

et al. 2010

2010 IEEE Wireless Communication and Networking Conference

View full text Add to dashboard Cite

Abstract-We consider a number of related problem formulations pertaining to adaptive subcarrier allocation in multiuser Orthogonal Frequency-Division Multiplexing (OFDM) systems, and prove that they are NP-hard. Thus there exist no known algorithms that can provide optimal solutions for all instances of these problems in polynomial time. We further prove that these problems are hard to approximate in polynomial time. Finally, we discuss qualitatively the settings under which worstcase performance is likely to be observed.

show abstract

Section: Related Workmentioning

confidence: 99%

Section: Related Workmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Subcarrier Allocation in Multiuser OFDM Systems: Complexity and Approximability

Huang

Gai

Krishnamachari

et al. 2010

2010 IEEE Wireless Communication and Networking Conference

View full text Add to dashboard Cite

show abstract

“…Due to its complexity, most solutions focus on heuristic-based algorithms (e.g. greedy) without considering approximation guarantees [14,15,17]. Different from these cellular network solutions, the main contribution of Optimus is to discover a linear transformation of the physical interference model under unregulated topology, and to analytically show that it guarantees an achievable allocation and provides a constant approximation ratio.…”

Section: Related Workmentioning

confidence: 99%

“…Second, other works have developed efficient solutions by transforming the problem into linear/convex programming. These solutions, however, must assume a regulated topology [12,13], or simplified interference models [1,[16][17][18][19]. Under unregulated topology and physical models, existing transformations no longer apply and there is no trivial extension.…”

Section: Introductionmentioning

confidence: 99%

Optimus: SINR-Driven Spectrum Distribution via Constraint Transformation

Cao

Yang

Zhou

et al. 2010

2010 IEEE Symposium on New Frontiers in Dynamic Spectrum (DySPAN)

View full text Add to dashboard Cite

How to distribute radio spectrum across network nodes is a critical problem in spectrum auctions and management. In this paper, we consider the problem of distributing spectrum using SINR-driven physical interference models. We propose Optimus, a new line of approximation algorithms that perform within a constant distance of min {2 α + 1, 10} from the optimum in terms of spectrum usage efficiency, where α ≥ 2 is the pathloss exponent. Different from conventional greedy solutions, Optimus applies a global optimization mechanism that transforms the spatial interference constraints into a set of linear constraints, reducing the original optimization into a linear/convex/separable programming problem. While linearization techniques have been applied in prior works, Optimus makes a new and important contribution by deriving a highly efficient constraint transformation applicable to general network configurations. Experiments using real network measurements and sophisticated propagation models show that Optimus outperforms existing solutions by 20-50% in spectrum utilization and is within 20% gap from the optimum. Optimus supports a wide variety of objective functions, and is applicable to many spectrum-driven applications such as spectrum auctions and spectrum admission control.

show abstract

Optimal power control in OFDMA cellular networks

et al. 2011

Self Cite

View full text Add to dashboard Cite

This article addresses the problem of allocating users to radio resources in the downlink of an OFDMA cellular system. We consider a classical multicellular environment with a realistic interference model and a margin adaptive approach, i.e., we aim at minimizing total transmission power while maintaining a certain given rate for each user. We discuss computational complexity issues of the resulting model and present a heuristic approach that finds optima under suitable conditions or reasonably good solutions in the general case. Computational experiments show the effectiveness of the proposed heuristic in a comparison with both a commercial state-of-the-art optimization solver and other approaches from the literature.

show abstract

Radio resource allocation problems for OFDMA cellular systems

Cited by 29 publications

References 15 publications

Subcarrier Allocation in Multiuser OFDM Systems: Complexity and Approximability

Subcarrier Allocation in Multiuser OFDM Systems: Complexity and Approximability

Optimus: SINR-Driven Spectrum Distribution via Constraint Transformation

Optimal power control in OFDMA cellular networks

Contact Info

Product

Resources

About