Downlink 8 Tx Codebook Sub-Sampling for Csi Feedback

1. A transceiver, comprising: a receiver for receiving; and a transmitter for transmitting via a Physical Uplink Control CHannel (PUCCH) a Channel State Information feedback signal having: a first mode with a first report jointly coding Rank Indicator (RI) and a first Precoding Matrix Indicator (PMI), and with a second report coding Channel Quality Indicator (CQI) and a second PMI, wherein said jointly coding the RI and the first PMI employs codebook sub-sampling into a maximum of 5 bits as follows: RI Codebook index (i 1 ) 1 0, 2, 4, 6, 8, 10, 12, 14 2 0, 2, 4, 6, 8, 10, 12, 14 3 0, 2 4 0, 2 and a second mode with a first report coding RI, and with a second report coding CQI and jointly coding the first PMI and the second PMI, wherein said jointly coding the first PMI and the second PMI employs codebook sub-sampling.

2. A transceiver, comprising: a receiver for receiving; and a transmitter for transmitting via a Physical Uplink Control CHannel (PUCCH) a Channel State Information feedback signal having: a first mode with a first report jointly coding Rank Indicator (RI) and a first Precoding Matrix Indicator (PMI), and with a second report coding Channel Quality Indicator (CQI) and a second PMI, wherein for a 2-layer capable user equipment said jointly coding RI and the first PMI employs codebook sub-sampling into 4 bits as follows: RI Codebook index (i 1 ) 1 0, 2, 4, 6, 8, 10, 12, 14 2 0, 2, 4, 6, 8, 10, 12, 14 and a second mode with a first report coding RI, and with a second report coding CQI and jointly coding the first PMI and the second PMI, wherein said jointly coding the first PMI and the second PMI employs codebook sub-sampling.

3. A transceiver, comprising: a receiver for receiving; and a transmitter for transmitting via a Physical Uplink Control CHannel (PUCCH) a Channel State Information feedback signal having: a first mode with a first report jointly coding Rank Indicator (RI) and a first Precoding Matrix Indicator (PMI), and with a second report coding Channel Quality Indicator (CQI) and a second PMI, wherein said jointly coding the RI and the first PMI employs codebook sub-sampling; and a second mode with a first report coding RI, and with a second report coding CQI and jointly coding the first PMI and the second PMI, wherein said jointly coding the first PMI and the second PMI employs codebook sub-sampling as follows for the first PMI: RI Codebook index (i 1 ) 1 0, 2, 4, 6, 8, 10, 12, 14 2 0, 2, 4, 6, 8, 10, 12, 14 3 0, 2 4 0, 2.

4. A transceiver, comprising: a receiver for receiving; and a transmitter for transmitting via a Physical Uplink Control CHannel (PUCCH) a Channel State Information feedback signal having: a first mode with a first report jointly coding Rank Indicator (RI) and a first Precoding Matrix Indicator (PMI), and with a second report coding Channel Quality Indicator (CQI) and a second PMI, wherein said jointly coding the RI and the first PMI employs codebook sub-sampling; and a second mode with a first report coding RI, and with a second report coding CQI and jointly coding the first PMI and the second PMI, wherein said jointly coding the first PMI and the second PMI employs codebook sub-sampling: for RI equal one joint coding the first PMI and the second PMI employs 7 bits or less, and for RI greater than one joint coding the first PMI and the second PMI employs 4 bits or less.