A user equipment, comprising: a receiver circuit configured to receive transmissions via at least six serving cells and less than or equal to 32 serving cells according to a carrier aggregation mode and to receive an aperiodic CSI reporting request comprising a CSI request field of 3 or 4 bits, wherein a CSI request field value indicates a set of serving cells for CSI reporting and wherein one or more of the serving cells is associated with the indicated set; a processor operably coupled to the receiver circuit and configured to: calculate one or more CSI parameters for each serving cell of the plurality of serving cells that is associated with the indicated set for CSI reporting; and generate an aperiodic CSI report based at least in part on the calculated CSI parameters for each serving cell associated with the indicated set; and a transmitter circuit configured to transmit the aperiodic CSI report to an eNB via a PUSCH, wherein the calculated one or more CSI parameters comprise a CQI for at least a first serving cell associated with the indicated set, and wherein the subband size associated with the CQI is increased in response to a determination that the total number of resource blocks of the serving cells associated with the indicated set exceeds a predefined number of resource blocks. a receiver circuit configured to receive transmissions via at least six serving cells and less than or equal to 32 serving cells according to a carrier aggregation mode and to receive an aperiodic CSI reporting request comprising a CSI request field of 3 or 4 bits, wherein a CSI request field value indicates a set of serving cells for CSI reporting and wherein one or more of the serving cells is associated with the indicated set; a processor operably coupled to the receiver circuit and configured to: calculate one or more CSI parameters for each serving cell of the plurality of serving cells that is associated with the indicated set for CSI reporting; and generate an aperiodic CSI report based at least in part on the calculated CSI parameters for each serving cell associated with the indicated set; and a transmitter circuit configured to transmit the aperiodic CSI report to an eNB via a PUSCH, wherein the calculated one or more CSI parameters comprise a CQI for at least a first serving cell associated with the indicated set, and wherein the subband size associated with the CQI is increased in response to a determination that the total number of resource blocks of the serving cells associated with the indicated set exceeds a predefined number of resource blocks. calculate one or more CSI parameters for each serving cell of the plurality of serving cells that is associated with the indicated set for CSI reporting; and generate an aperiodic CSI report based at least in part on the calculated CSI parameters for each serving cell associated with the indicated set; and a transmitter circuit configured to transmit the aperiodic CSI report to an eNB via a PUSCH, wherein the calculated one or more CSI parameters comprise a CQI for at least a first serving cell associated with the indicated set, and wherein the subband size associated with the CQI is increased in response to a determination that the total number of resource blocks of the serving cells associated with the indicated set exceeds a predefined number of resource blocks.