Maximizing the sum rate in symmetric networks of interfering links

  • Authors:

  • Sibi Raj Bhaskaran;Stephen V. Hanly;Nasreen Badruddin;Jamie S. Evans

  • Affiliations:

  • Department of Electrical Engineering, IIT Bombay, Powai, Mumbai, India;Department of Electrical and Computer Engineering, NUS, Singapore;Department of Electrical and Electronic Eng., University of Melbourne, Parkville, Vic., Australia;Department of Electrical and Electronic Eng., University of Melbourne, Parkville, Vic., Australia

  • Venue:
  • IEEE Transactions on Information Theory
  • Year:
  • 2010

Quantified Score

Hi-index 754.84

Visualization

Abstract

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 (√ε) 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/√2. If √ε