Ergodic Interference Alignment with Delayed Feedback

We propose new ergodic interference alignment techniques for $K$-user interference channels with delayed feedback. Two delayed feedback scenarios are considered – delayed channel information at transmitter (CIT) and delayed output feedback. It is proved that the proposed techniques achieve total $2K\mathrm{/}(K+2)$ DoF which is higher than that by the retrospective interference alignment for the delayed feedback scenarios.