Methods and apparatus are disclosed for a UE and its serving base station in 5G NR systems to signal channel scan or channel sensing to allow channel occupancy time (COT) sharing before transmissions. The COT sharing may be initiated by the base station or by the UE by asserting a CCA indication to enable channel sensing by a UE or base station, respectively. When the UE receives and decodes the asserted CCA indication during downlink transmission, the UE may perform channel sensing during a short interframe space (SIFS) between the downlink transmission and a scheduled uplink transmission. When the UE detects that the sensed RF energy across an intended transmission band is greater than an energy detect threshold, the UE may refrain from transmitting during the scheduled uplink transmission. Otherwise or when the CCA indication is de-asserted, the UE may transmit during the scheduled uplink transmission without performing channel sensing.