A communications system comprising - a wireless transmit/receive unit, WTRU, configured to transmit a channel state information, CSI, report; and - a base station (114, 160, 180) configured to transmit an aperiodic CSI reporting request for the WTRU to transmit the CSI report, wherein the WTRU comprises: a receiver configured to receive the aperiodic CSI reporting request on a physical downlink control channel, PDCCH, in a slot containing multiple symbols; circuitry configured to determine a time gap between a last symbol of the PDCCH of which the aperiodic CSI reporting request is received and a first uplink symbol of an uplink channel for transmission of a corresponding CSI report, wherein the determination of the time gap includes consideration of a timing advance value; the circuitry configured to determine a CSI processing time threshold based on subcarrier spacing used by the WTRU for communication with the base station (114, 160, 180), wherein the CSI processing time threshold is a function of a type of CSI to be reported and the subcarrier spacing, and determine whether the determined time gap is shorter than the determined CSI processing time threshold; and a transmitter configured: to transmit, on a condition that the determined time gap is not shorter than the determined CSI processing time threshold, the CSI report to the base station (114, 160, 180), in response to the CSI reporting request, not to transmit, on a condition that the determined time gap is shorter than the determined CSI processing time threshold, the CSI report. - a wireless transmit/receive unit, WTRU, configured to transmit a channel state information, CSI, report; and - a base station (114, 160, 180) configured to transmit an aperiodic CSI reporting request for the WTRU to transmit the CSI report, a receiver configured to receive the aperiodic CSI reporting request on a physical downlink control channel, PDCCH, in a slot containing multiple symbols; circuitry configured to determine a time gap between a last symbol of the PDCCH of which the aperiodic CSI reporting request is received and a first uplink symbol of an uplink channel for transmission of a corresponding CSI report, wherein the determination of the time gap includes consideration of a timing advance value; the circuitry configured to determine a CSI processing time threshold based on subcarrier spacing used by the WTRU for communication with the base station (114, 160, 180), wherein the CSI processing time threshold is a function of a type of CSI to be reported and the subcarrier spacing, and determine whether the determined time gap is shorter than the determined CSI processing time threshold; and a transmitter configured: to transmit, on a condition that the determined time gap is not shorter than the determined CSI processing time threshold, the CSI report to the base station (114, 160, 180), in response to the CSI reporting request, not to transmit, on a condition that the determined time gap is shorter than the determined CSI processing time threshold, the CSI report. to transmit, on a condition that the determined time gap is not shorter than the determined CSI processing time threshold, the CSI report to the base station (114, 160, 180), in response to the CSI reporting request, not to transmit, on a condition that the determined time gap is shorter than the determined CSI processing time threshold, the CSI report.