IQQuadErr (LTE-Advanced)

IQQuadErr shows the IQ quadrature error, or angle error between I and Q for a transmit antenna, averaged over the PDSCH Physical Downlink Shared Channel subcarriers on a C-RS Cell-specific RS antenna port for all VSA measurement channels (Rx0 = Measurement Channel 1).

IQQuadErr is expressed in number of degrees. Positive values indicate that the angle between I and Q is greater than 90 degrees. Negative values indicate that the angle between I and Q is less than 90 degrees.

IQQuadErr is calculated for each C-RS antenna port. When a C-RS/Rx path is present, the MIMO Info Table will show the IQ quadrature error for the corresponding antenna port. C-RS/Rx paths with the same C-RS antenna port but different Rx channels will show the same value.

The MIMO Info Table will show "---" for IQ data results that cannot be calculated from the demodulated data. Cases where the IQ metrics cannot be calculated are as follows:

The signal has the Precoding mode set to SpMux (Spatial Multiplexing), CDD set to W/o CDD, and the number of layers is less than the number of transmit antennas.
The signal has only UE-RS UE-specific Reference Signal PDSCH allocations (MIMO Info Table data results do not include PDSCH transmitted on UE User Equipment (e.g. cell phone)-RS antenna ports).
The signal in the Measurement Interval does not contain at least one PDSCH subcarrier that has a corresponding PDSCH subcarrier in the frequency-mirrored location on the other side of the DC axis.
The transmitted data is identical on two or more layers and Codebook Idx is set to zero.
The number of measurement channels is less than the number of C-RS antenna ports.