Record Details

Maximizing the Sum Rate in Symmetric Networks of Interfering Links

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Maximizing the Sum Rate in Symmetric Networks of Interfering Links
 
Creator BHASKARAN, SR
HANLY, SV
BADRUDDIN, N
EVANS, JS
 
Subject digital subscriber lines
dynamic spectrum management
power-control
complexity
channels
systems
power control
resource allocation
spectrum allocation
sum rate maximization
interference mitigatio
 
Description We consider the power optimization problem of maximizing the sum rate of a symmetric network of interfering links in Gaussian noise. All transmitters have an average transmit power constraint, the same for all transmitters. This problem has application to DSL, as well as wireless networks. We solve this nonconvex problem by indentifying some underlying convex structure. In particular, we characterize the maximum sum rate of the network, and show that there are essentially two possible states at the optimal solution depending on the cross-gain (root is an element of) between the links, and/or the average power constraint: the first is a wideband (WB) state, in which all links interfere with each other, and the second is a frequency division multiplexing (FDM) state, in which all links operate in orthogonal frequency bands. The FDM state is optimal if the cross-gain between the links is above 1/root 2. If root is an element of < 1/root 2, then FDM is still optimal provided the SNR of the links is sufficiently high. With root is an element of < 1/root 2, the WB state occurs when the SNR is low, but as we increase the SNR from low to high, there is a smooth transition from the WB state to the FDM state: For intermediate SNR values, the optimal configuration is a mixture, with some fraction of the bandwidth in the WB state, and the other fraction in the FDM state. We also consider an alternative formulation in which the power is mandated to be frequency flat. In this formulation, the optimal configuration is either all links at full power, or just one link at full power. In this setting, there is an abrupt phase transition between these two states.
 
Publisher IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
 
Date 2011-08-01T07:01:33Z
2011-12-26T12:53:18Z
2011-12-27T05:40:35Z
2011-08-01T07:01:33Z
2011-12-26T12:53:18Z
2011-12-27T05:40:35Z
2010
 
Type Article
 
Identifier IEEE TRANSACTIONS ON INFORMATION THEORY, 56(9), 4471-4487
0018-9448
http://dx.doi.org/10.1109/TIT.2010.2054652
http://dspace.library.iitb.ac.in/xmlui/handle/10054/8374
http://hdl.handle.net/10054/8374
 
Language en