IQ Phase Error (GSM/EDGE/EDGE Evolution)

IQ Phase Error traces show the phase error between the measured and reference IQ signals. This error is calculated and displayed for each symbol point.

$image\IQMagIQPhaseError_wmf.jpg$

For IQ Phase Error, the VSA compares the unwrapped phase of the measured IQ signal with the unwrapped phase of the reference IQ signal at each symbol point. The VSA then shows the phase difference between the two signals in the IQ Phase Error trace.

IQ Mag Error and IQ Phase Error compare all points in the measured IQ signal and reference IQ signal. For all modulation schemes, there is only one point per symbol, except for GMSK, where there are 10 points per symbol.

When using band-power markers, all the points on the IQ Mag Error and IQ Phase Error traces within band-power markers are included in band-power calculations, unlike the Summary Table data results which only use the symbol decision points for calculating error summary information.

The measured IQ signal can be viewed in the IQ Meas Time trace and the reference IQ signal in the IQ Ref Time trace.