Retrospective Interference Alignment for Interference Channels With Delayed Feedback
The capacity of the most recent network architectures, such as femtocells, is severely limited by interference. This has spurred an intense research on the M-user interference channel, in which M transmitter/receiver pairs interfere with each other. Very striking recent results, though, disproved it by showing that the degrees of freedom per user in the interference channel scale as 1/2 independently of the number of interferers when a transmission scheme called INterference alignment (IN) is applied. These very promising results presuppose a complete knowledge on the Channel State Information at the Transmitters (CSIT).