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How to measure CQI (Channel quality indicator)

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How to measure CQI (Channel quality indicator)
posted Jul 23, 2013 by Sumit Pokharna

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The Channel Quality Indicator (CQI) contains information sent from a UE to the eNode-B to indicate a suitable downlink transmission data rate, i.e., a Modulation and Coding Scheme (MCS) value. CQI is a 4-bit integer and is based on the observed signal-to-interference-plus-noise ratio (SINR) at the UE. The CQI estimation process takes into account the UE capability such as the number of antennas and the type of receiver used for detection. This is important since for the same SINR value the MCS level that can be supported by a UE depends on these various UE capabilities, which needs to be taken into account in order for the eNode-B to select an optimum MCS level for the transmission. The CQI reported values are used by the eNode-B for downlink scheduling and link adaptation, which are important features of LTE.
LTE supports wideband and subband CQI reporting. A wideband CQI value is a single 4-bit integer that represents an effective SINR as observed by the UE over the entire channel bandwidth.

answer Jul 23, 2013 by Giri Prasad
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+3 votes

How the CQI reporting period and the DL throughput are related?

The lower CQI reporting period, the better link adaptation, so better Modulation and Coding Scheme (MCS) assignment and higher throughput?

If this is true, the best option should be to set CQI-PMI-ConfigIndex to lower values, am I right?

CQI-PMI = Channel Quality Indicator - PreCoding-matrix-Indicator.