Doppler Shift Compensation Assisted by RIS Systems in High-Mobility Communications

The Doppler shift in the signal frequency caused by the relative movement of the receiver is considered to be detrimental for communication systems. Although this problem has been studied extensively, it is still relevant given the renewed interest on high-mobility communications. On the other hand, novel solutions such as the reconfigurable intelligent surface (RIS) can be repurposed for tackling the Doppler shift in high-mobility communication systems. Despite not being its usual primary goal, we show in this work that the RIS can compensate the Doppler shift at a small cost in performance.