26 research outputs found
Weighted Max-Min Resource Allocation for Frequency Selective Channels
In this paper, we discuss the computation of weighted max-min rate allocation
using joint TDM/FDM strategies under a PSD mask constraint. We show that the
weighted max-min solution allocates the rates according to a predetermined rate
ratio defined by the weights, a fact that is very valuable for
telecommunication service providers. Furthermore, we show that the problem can
be efficiently solved using linear programming. We also discuss the resource
allocation problem in the mixed services scenario where certain users have a
required rate, while the others have flexible rate requirements. The solution
is relevant to many communication systems that are limited by a power spectral
density mask constraint such as WiMax, Wi-Fi and UWB
Coordination and Bargaining over the Gaussian Interference Channel
This work considers coordination and bargaining between two selfish users
over a Gaussian interference channel using game theory. The usual information
theoretic approach assumes full cooperation among users for codebook and rate
selection. In the scenario investigated here, each selfish user is willing to
coordinate its actions only when an incentive exists and benefits of
cooperation are fairly allocated. To improve communication rates, the two users
are allowed to negotiate for the use of a simple Han-Kobayashi type scheme with
fixed power split and conditions for which users have incentives to cooperate
are identified. The Nash bargaining solution (NBS) is used as a tool to get
fair information rates. The operating point is obtained as a result of an
optimization problem and compared with a TDM-based one in the literature.Comment: 5 pages, 4 figures, to appear in Proceedings of IEEE ISIT201
Alternating-Offer Bargaining Games over the Gaussian Interference Channel
This paper tackles the problem of how two selfish users jointly determine the
operating point in the achievable rate region of a two-user Gaussian
interference channel through bargaining. In previous work, incentive conditions
for two users to cooperate using a simple version of Han-Kobayashi scheme was
studied and the Nash bargaining solution (NBS) was used to obtain a fair
operating point. Here a noncooperative bargaining game of alternating offers is
adopted to model the bargaining process and rates resulting from the
equilibrium outcome are analyzed. In particular, it is shown that the operating
point resulting from the formulated bargaining game depends on the cost of
delay in bargaining and how bargaining proceeds. If the associated bargaining
problem is regular, a unique perfect equilibrium exists and lies on the
individual rational efficient frontier of the achievable rate region. Besides,
the equilibrium outcome approaches the NBS if the bargaining costs of both
users are negligible.Comment: 8 pages, 6 figures, to appear in Proceedings of Forty-Eighth Annual
Allerton Conference on Communication, Control, and Computin
Competitive Spectrum Management with Incomplete Information
This paper studies an interference interaction (game) between selfish and
independent wireless communication systems in the same frequency band. Each
system (player) has incomplete information about the other player's channel
conditions. A trivial Nash equilibrium point in this game is where players
mutually full spread (FS) their transmit spectrum and interfere with each
other. This point may lead to poor spectrum utilization from a global network
point of view and even for each user individually.
In this paper, we provide a closed form expression for a non pure-FS
epsilon-Nash equilibrium point; i.e., an equilibrium point where players choose
FDM for some channel realizations and FS for the others. We show that operating
in this non pure-FS epsilon-Nash equilibrium point increases each user's
throughput and therefore improves the spectrum utilization, and demonstrate
that this performance gain can be substantial. Finally, important insights are
provided into the behaviour of selfish and rational wireless users as a
function of the channel parameters such as fading probabilities, the
interference-to-signal ratio
Compensation-based Game for Spectrum Sharing in the Gaussian Interference Channel
This paper considers an optimization problem of sum-rate in the Gaussian frequency-selective channel. We construct a competitive game with an asymptotically optimal compensation to approximate the optimization problem of sum-rate. Once the game achieves the Nash equilibrium, all users in the game will operate at the optimal sum-rate boundary. The contributions of this paper are twofold. On the one hand, a distributed power allocation algorithm called iterative multiple waterlevels water-filling algorithm is proposed to efficiently achieve the Nash equilibrium of the game. On the other hand, we derive some sufficient conditions on the convergence of iterative multiple waterlevels water-filling algorithm in this paper. Through simulation, the proposed algorithm has a significant improvement of the performance over iterative water filling algorithm and achieves the close-to-optimal performance