Remote Operation
Publication 31470-001, Rev C, November 2, 2017
3-89
3.8
Crest Factor
The Crest Factor feature holds on to the highest instantaneous power measured from the time the feature is
enabled until it is reset; it is similar to the Peak Hold feature, except that the measurement is expressed as a
ratio in relation to average power.
Like the Peak Hold feature, the Crest Factor feature also has the same minimum average power level restriction
of -20 dBm. This has been implemented to increase accuracy and maintain wide bandwidth of Crest Factor
measurement over the peak power range of -20 dBm to +20 dBm. The Crest Factor selection will also affect
Histogram measurement if there is power below -20 dBm. To obtain accurate average power measurements
below -20 dBm, the Crest Factor feature should be disabled.
NOTE:
The Crest Factor feature can only be used in the standard measurement collections modes (not in
the GPIB fast modes), and only in a modulated measurement mode (MAP, PAP or BAP). Crest Factor is
not recommended for use in combination with the V
PROP
F function.
3.8.1
Enabling the Crest Factor Feature
The Crest Factor feature is enabled or disabled by one of two function codes:
Syntax:
[AE or BE] [CR0 or CR1]
[AE or BE] prefix specifies Sensor A or Sensor B
[CR0] disables the Crest Factor function. Like the PH0 and MN0 commands, the CR0 command
will disable Peak Hold and Min/Max measurements
[CR1] enables the Crest Factor function. Sending the CR1 command after Crest Factor is
enabled will reset both the Crest Factor and Peak Hold functions (See Section 3.19.7)
Example:
AE CR1
! ENABLES THE CREST FACTOR FEATURE FOR SENSOR A
Example 2:
BE CR0
! DISABLES THE CREST FACTOR FEATURE FOR SENSOR B
3.8.2
Reading the Crest Factor Value
The Crest Factor value is read over the bus using a simple command:
Syntax:
[AE or BE] CRF
[AE or BE] prefix specifies Sensor A or Sensor B
CRF queries the current Crest Factor value
Example:
AE CRF
! SENDS THE CREST FACTOR VALUE FOR SENSOR A
The Crest Factor feature monitors the maximum power as it is measured, but does not provide any feedback to
the controller until a CRF command is received. To monitor for a limit violation, the Limits feature may be more
useful (See Section 3.15).
Содержание 8650B Series
Страница 3: ...Series 8650B Universal Power Meters Publication 31470 001 Rev C November 2 2017 iii ...
Страница 18: ......
Страница 32: ......
Страница 78: ......
Страница 236: ......
Страница 244: ......
Страница 258: ......
Страница 263: ...Menu Structure Publication 31470 001 Rev C November 2 2017 D 3 Figure D 3 Modulation Sensor B Setup Menu Structure ...
Страница 265: ...Menu Stucture Publication 31470 001 Rev C November 2 2017 Page D 5 Figure D 4 Meter Setup Menu Structure ...
Страница 267: ...Publication 31470 001 Rev C November 2 2017 Last page of the document ...