Atec Agilent-E8364B - Manual (Page 121)

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Table 37. Test Port Input (Group Delay) a
Description Specification Supplemental Information (typ.)
Aperture (selectable) (frequency span)/(number of points -
1)
Maximum Aperture 20% of frequency span
Range 0.5 x (1/minimum aperture)
Maximum Delay Limited to measuring no more than
180° of phase change within the
minimum aperture.)
Accuracy See graph below. Char.
The following graph shows characteristic group delay accuracy with full 2-port calibration and a 10 Hz IF
bandwidth. Insertion loss is assumed to be < 2 dB and electrical length to be ten meters.
NOTE: The following graph also applies to the “C” model of the analyzers.
In general, the following formula can be used to determine the accuracy, in seconds, of specific group delay
measurement:
±Phase Accuracy (deg)/[360 × Aperture (Hz)]
Depending on the aperture and device length, the phase accuracy used is either incremental phase accuracy or
worst case phase accuracy.
a Group delay is computed by measuring the phase change within a specified frequency step (determined by the frequency span and the
number of points per sweep).