Comp IQ Meas Spec and IQ Ref Spec (cdma2000/1xEV-DV)

Menu Path: Trace > Data > Channel 1 Comp > IQ Meas Spec
Trace > Data > Channel 1 Comp > IQ Ref Spec

When cdma2000/1xEV-DV demodulation is enabled, Comp IQ Meas Spec and Comp IQ Ref Spec traces are the frequency spectrum of the Comp IQ Meas Time or Comp Ref Time trace data. The VSA produces the spectrum by Windowing and FFTing the time trace data. The spectrum represents the signal AFTER filtering.

The trace data is computed from the first PCG in the measurement and the Measurement Interval and Measurement Offset parameter settings are ignored (see Measurement Interval and Offset).

Marker Frequency Correction

The VSA's demodulator removes carrier-frequency error. Therefore, in the composite error vector spectrum display, add the carrier-frequency error to marker readouts to obtain exact frequency information. The carrier-frequency error (Freq Err) is shown in the Composite Error Summary trace data.

By default, the VSA shows the log(dB) magnitude when IQ measured spectrum is selected. The same is true for I/Q reference.

See Also

Chan Error Vector Time

Channel 1 Comp Trace Data

About Trace Data (cdma2000/1xEV-DV)

VSA Concepts (Windowing and FFTing)