The net degrees of freedom (DoF ) describe the efficiency of a protocol in terms of network throughput at high signal-to-noise ratio (SNR). As the conventional DoF, it captures how the achievable user data rate grows as SNR increases, but also takes into account the limited channel state information at the transmitters (CSIT), and required protocol overheads. This work studies the impact of short channel coherence time for the K-user Multiple-Input Single-Output (MISO) Interference Channel (IC) by means of the net DoF. We propose different protocols, combining techniques that exploit different levels of CSIT (delayed, current or no CSIT), and elucidating which performs better as a function of user mobility.

Peer Reviewed