Pilot-assisted interference alignment in time-selective fading channels

The spectral efficiency achievable by IA (interference alignment) in a K-user interference channel is studied in the face of time-selective fading explicitly estimated through pilot-symbol observations. The robustness of IA is assessed through a joint optimization of the pilot overhead and the IA update interval, which are characterized-in the high-power conditions where IA is relevant-as solutions of a fixed-point equation.