5G/NR - SDL                                                     Home : www.sharetechnote.com






SDL stands for Supplimentary Downlink. It may sound similar to SUL, but I think the motivation for SDL is a little bit different from SUL. The main motivation of SUL would be for improving the coverage by easing the UL power restriction in high frequency (refer to SUL page for further details), but the main motivation for SDL would not be for coverage expantion, it would be more for improving the utilization of spectrum resources which has been under-utilized (See this article for an example use case)


The frequency spectrum allocated for SDL by 3GPP are as follows :







[1] Easiest way to supplement downlink capacity (Nokia)