Error Vector Time (Component Test)

The Error Vector Time trace shows the normalized error vector (measured minus reference), in percent, computed between corresponding symbol points in the IQ Meas and IQ Ref traces. This trace drives the EVM summary result.

The following graphic shows the calculation of the error vector magnitude (EVM Error vector magnitude (EVM): A quality metric in digital communication systems. See the EVM metric in the Error Summary Table topic in each demodulator for more information on how EVM is calculated for that modulation format.) for a symbol point. The diagram on the right shows how the error vector itself is calculated.

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Trace Data Formats

It is important to remember that the Error Vector Time trace is a time record made up of complex, time-domain data. Each point in the time record has two components: I and Q. To make sense of the data, select an appropriate trace data format (Trace > Format > Format: drop-down list).

Linear Mag: EVM (Error Vector Magnitude)
Real(I): I component of the error vector
Imag(Q) : Q component of the error vector
Wrap Phase: Error Vector Phase error