English

The Wideband Slope of Interference Channels: The Large Bandwidth Case

Information Theory 2011-11-15 v2 math.IT

Abstract

It is well known that minimum received energy per bit in the interference channel is -1.59dB as if there were no interference. Thus, the best way to mitigate interference is to operate the interference channel in the low-SNR regime. However, when the SNR is small but non-zero, minimum energy per bit alone does not characterize performance. Verdu introduced the wideband slope S_0 to characterize the performance in this regime. We show that a wideband slope of S_0/S_{0,no interference}=1/2 is achievable. This result is similar to recent results on degrees of freedom in the high SNR regime, and we use a type of interference alignment using delays to obtain the result. We also show that in many cases the wideband slope is upper bounded by S_0/S_{0,no interference}<=1/2 for large number of users K .

Keywords

Cite

@article{arxiv.1010.5661,
  title  = {The Wideband Slope of Interference Channels: The Large Bandwidth Case},
  author = {Minqi Shen and Anders Høst-Madsen},
  journal= {arXiv preprint arXiv:1010.5661},
  year   = {2011}
}