IQ Mag Error (GSM/EDGE/EDGE Evolution)

The IQ Mag Error trace shows the magnitude error between the measured and reference IQ signals. This error is calculated and displayed for each symbol point.

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For IQ Mag Error, the VSA compares the magnitude of the measured IQ signal with the magnitude of the reference IQ signal. The VSA then shows the difference, in magnitude, between the two signals on the IQ Mag Error trace.

When Normalize IQ Traces is cleared, the VSA shows the absolute magnitude error for each time point in the current Timeslot.

When normalization is ON, the VSA shows the magnitude error as a percentage of the RMS average of the ideal symbol points. The average is performed over the data in the demodulated timeslot. Any points in between symbol points (when demodulating GMSK Gaussian Minimum Shift Keying) are not included in the RMS average of the ideal symbol points.

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.