subframe, the UE transmits only the aperiodic report in that subframe. When reporting RI, the UE reports a single instance of the number of useful transmission layers. For each RI reporting interval during closed-loop spatial mul- tiplexing, a UE determines an RI from the supported set of RI values for the cor- responding eNodeB and UE antenna configuration and reports the number in each RI report. For each RI reporting interval during open-loop spatial multiplexing, a UE determines an RI for the corresponding eNodeB and UE antenna configuration © 2009 by Taylor & Francis Group, LLC Long Term Evolution: 3 GPP LTE Radio and Cellular Technology Table 5.7 Physical Channels for Aperiodic or Periodic CQI Reporting Periodic CQI Reporting Aperiodic CQI Reporting Scheduling Mode Channels Channel Frequency nonselective PUCCH; PUSCH PUSCH Frequency selective PUCCH; PUSCH PUSCH in each reporting interval and reports the detected number in each RI report to support selection between RI = 1 transmit diversity and RI > 1 large-delay CDD open-loop spatial multiplexing. When reporting PMI, the UE reports either a single or a multiple PMI report. The number of RBs represented by a single UE PMI report can be NDL RB DL or a smaller subset of RBs. The number of RBs represented by a single PMI report is semi- statically configured by higher-layer signaling. A UE is restricted to reporting PMI and RI within a precoder codebook subset specified by a bitmap configured by higher-layer signaling. For a specific precoder codebook and associated transmis- sion mode, the bitmap can specify all possible precoder codebook subsets that the UE can assume the eNB may be using when the UE is configured in the relevant transmission mode. The set of sub-bands (S) that a UE evaluates for CQI reporting is semistatically configured by higher layers. A sub-band is a set of k contiguous PRBs, where k is also semistatically configured by higher layers. Note that the last sub-band in set S may have fewer than k contiguous PRBs, depending on NDL The number