The cell carriers are mainly planning to use the 5GHz band for small cell indoor deployments (distributed antenna systems). The 3GPP and the Wi-Fi Alliance are going back and forth to ensure that if LTE and Wi-Fi networks are forced to share the same channel that it will at worst degrade the Wi-Fi performance as if there were another Wi-Fi network sharing the channel.
> ... if LTE and Wi-Fi networks are forced to share the same channel ... at worst degrade the Wi-Fi performance as if there were another Wi-Fi network sharing the channel.
Unfortunately that's not true in implementation because LTE-U doesn't know or care about the wifi channel announce timings. By piping up whenever it wants to wifi throughput actually degrades more than 70% at minimum LTE-U duty cycle spec (50%) and up to almost completely, ~99% reduction, at max allowed LTE-U duty cycle (90%) spec.
No matter what they say this is a spectrum grab and LTE-U will degrade 5 GHz wifi to the point of being unusable.