Approximate Capacity of the Two-User Gaussian Interference Channel with   Noisy Channel-Output Feedback
  In this research report, an achievability region and a converse region for the two-user Gaussian interference channel with noisy channel-output feedback (G-IC-NOF) are presented. The achievability region is obtained using a random coding argument and three well-known techniques: rate splitting, superposition coding and backward decoding. The converse region is obtained using some of the existing perfect-output feedback outer-bounds as well as a set of new outer-bounds that are obtained by using genie-aided models of the original G-IC-NOF. Finally, it is shown that the achievability region and the converse region approximate the capacity region of the G-IC-NOF to within a constant gap in bits per channel use. 
Victor Quintero, Samir M. Perlaza, I\~naki Esnaola, Jean-Marie Gorce
cs.IT math.IT