A user equipment (UE) is configured to perform channel estimation. The UE operates in a current channel estimation mode comprising either one of a first mode or a second mode, wherein the first mode comprises receiving first reference signals (RS) having a first RS overhead and wherein the second mode comprises receiving second reference signals (RS) having a second RS overhead, receives a network indication to switch from the current channel estimation mode to a new channel estimation mode comprising the other one of the first mode or second mode, transmits an acknowledgment to the network that the network indication was received and switches from the current channel estimation mode to the new channel estimation mode in accordance with the network indication.