Agilent Technologies E9300 manual Speed and Averaging, Summary

Measurement Accuracy and Speed

power path (-10 dBm to +20 dBm) should be used to ensure a more accurate measurement of this signal. However, range holding in “UPPER” (the high power path), for a more accurate measurement, results in considerably more filtering.

Speed and Averaging

The same signal also requires that consideration is given to measurement speed. As shown above, in autoranging mode the Agilent EPM series power meter selects the low power path in the Agilent E-series E9300 power sensor. With auto-averaging also configured, minimal filtering is applied. Values of 1 to 4 for average power levels above -20 dBm are used in the low power path. (Refer to “Auto-averaging Settings” on page 21.)

If the range is held in “UPPER” for more accuracy, the measurement is slower. More filtering is applied due to the increase in noise susceptibility at the less sensitive area of the high power path. Values of 1 to 128 for average power levels less than -10 dBm are used. (Again, refer to “Auto-averaging Settings” on page 21.) Manually lowering the filter settings speeds up the measurement but can result in an unwanted level of jitter.

Summary

Attention must be paid to signals whose average power levels are in the low power path range whilst their peaks are in the high power path range. You can achieve best accuracy by selecting the high power path or best speed by selecting the low power path.

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