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What is CQI PMI RI in LTE?

Well, we had discussed about uplink channel state information  Difference between SRS and DMRS by reference signals (SRS and DMRS). Now to achieve 1Gbps or more downlink speed in LTE with effective resource utilization of full bandwidth available,   CQI PMI RI and many more parameter play very important role. So what are CQI, PMI and RI in LTE? CQI (Channel Quality Indicator) , reported by UE to eNB. UE indicates modulation scheme and coding scheme to eNB , if used I would be able to demodulate and decode the transmitted downlink   data with maximum block error rate 10%. To predict the downlink channel condition, CQI feedback by the UE is an input. CQI reporting can be based on PMI and RI. Higher the CQI value (from 0 to 15) reported by UE, higher the modulation scheme (from QPSK to 64QAM ) and higher the coding rate will be used by eNB to achieve higher efficiency.  PMI (Precoding Matrix Indicator) , UE indicates to eNB , which precoding ma...