On Channel Output Feedback in Deterministic Interference Channels

Sahai A., Aggarwal V., YÜKSEL TURGUT A. M., Sabharwal A.

IEEE Information Theory Workshop (ITW), Taormina, Italy, 11 - 16 October 2009, pp.298-302 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.1109/itw.2009.5351427
  • City: Taormina
  • Country: Italy
  • Page Numbers: pp.298-302
  • Middle East Technical University Affiliated: No


In this paper, we study the effect of channel output feedback on the sum capacity in a two-user symmetric deterministic interference channel. We find that having a single feedback link from one of the receivers to its own transmitter results in the same sum capacity as having a total of 4 feedback links from both the receivers to both the transmitters. Hence, from the sum capacity point of view, the three additional feedback links are not helpful. We also consider a half-duplex feedback model, where the forward and the feedback resources are symmetric and time-shared. Surprisingly, we find that there is no gain in sum-capacity with feedback in a half-duplex feedback model, when interference links have more capacity than direct links.