MDO3000 Programmer Manual.pdf - 第82页

Command Groups Ta b l e 2 - 3 7 : R F C ommands Item Description MARKER:M<x>:AMPLitude: ABSolute? This query ret urns the actual amplitude (vertical) valu e of the either of the two manual markers that are availabl…

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Command Groups
When the two man
ual markers are turned on, the Reference Marker is no longer
automatically attached to the highest amplitude peak. It can now be moved toany
desired location. This enables easy measurement of any part of the spectrum,
as well as delta measurements to any part of the spectrum. This also lets you
measure non-peak spectral content of interest. The readouts for manual markers
indicate frequency, amplitude and noise (just like automatic marker readouts).
Taking Auto
matic
Measurements in the
Frequency Domain
You can take three automatic measurements in the frequency domain:
1. Channel Power (CP) — The total power within the bandwidth, defined by
the Channel Width.
2. Adjacent Channel Power Ratio (ACPR) — The power in the main channel
and the ratio of channel power to main power, for the upper and lower halves of
each adjacent channel.
3. Occupied Bandwidth (OBW) — The bandwidth that contains the specified
percentage of power within the analysis bandwidth.
Triggering using RF
Power L evel as a Source;
Searching
The ability to use the RF power level as the source for edge triggering and
searching is provided standard with the MDO4000/B and MDO4000C with
option SA3 or SA6 series models. With the MDO4TRIG (Advanced Trigger)
application module installed, the RF power level can also be used as the source
for p
ulse width, time-out, runt, logic, and sequence triggering. (See page 2-76,
Trigger Command Group.) A number of search commands are also available.
(See page 2-61, Search Command Group.)
Transfe rring and Saving
RF Trace Information
Yo
u can perform waveform transfer commands and queries using RF traces. (See
page 2-95, Waveform Transfer Command Group.)
RF
traces can be saved to an .ISF or .CSV file for subsequent recall to any of the
4 internal reference memory locations. The oscilloscope can also save, butnot
recall, RF acquisitions as .TIQ files. You can import .TIQ files into Tektronix
SignalVu-PC software (PC based), SignalVu software (oscilloscope based),
RSAVu software (PC based) or into a Tektronix real-time spectrum analyzer for
pulse analysis and demodulation analysis. (See page 2-58, Save and Recall
Command Group.)
NOTE. The RF input replaces the Aux Input connector on the front panel,
therefore aux-in commands and arguments are not supported on the MDO4000/B,
MDO4000C with option SA3 or SA6, and MDO3000 models with 4-channels.
MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual 2-51
Command Groups
Table 2-37: RF C
ommands
Item Description
MARKER:M<x>:AMPLitude:
ABSolute?
This query ret
urns the actual amplitude (vertical) value of the either of the two manual markers
that are available for frequency domain traces, in dBm.
MARKER:M<x>
:AMPLitude:
DELTa?
This query returns the delta amplitude (vertica l) value of either of the two manual markers that
are available for frequency domain traces, in relation to the Reference Marker.
MARKER:M<x>:FREQuency:
ABSolute
This command specifies the actual frequency (horizontal) value of either of the two manual
markers tha
t a re available for frequency domain traces.
MARKER:M<
x>:FREQuency:
DELTa?
This query
returns the delta frequency (horizontal) value of either of the two manual markers
that are available for frequency domain traces, in relation to the Reference Marker.
MARKER:M<x>:NOISEDensity?, This c ommand returns the noise density of the RF_NORMal trace at the specified marker
position in <RF Units>/Hz units, where <RF Units> are the units specified by the command
RF:UNIts
.
MARKER:
M<x>:PHASENoise?
This com
mand returns the phase noise of the RF_NORMal trace at the specified marker
position in dBc/Hz units.
MARKER:
MANual
This command switches on or off the manual markers a and b that are available for frequency
domain traces.
MARKER:PEAK:EXCURsion This command specifies the excursion value, in user-selected units, for the frequency domain
trace a
utomatic peak markers. You can select the units with the command RF:UNIts.
MARKER:PEAK:MAXimum
This c
ommand specifies the maximum number of frequency domain trace peaks that should
have automatic markers associated with them. This can be a number between 1 and 11.
MARKER:PEAK:STATE This command switches on or off the automatic peak markers that are available for frequency
domain traces. The default is 1 (on). There are up to 11 automatic markers.
MARKER:PEAK:THReshold
This command specifies the threshold value, in the same vertical units as the source waveform,
of t
he automatic peak markers available f or frequency domain traces. (Use the RF:UNIts
to specify the units.)
MAR
KER:REFERence
This command changes the Center Frequency to the frequency indicated by the Reference
Marker, in effect moving the Reference Marker to the center of the screen.
MARKER:REFERence:
AMPlitude?
This query returns the amplitude (vertical) value of the Reference Marker in dBm when markers
ar
e turned on (using the command MARKER:PEAK :STATE or MARKER:MANual).
MARKER:REFERence:
F
REQuency?
T
his query returns the frequency of the Reference Marker when the frequency domain
trace markers have been turned on (using either the command MARKER:P EAK:STATE or
MARKER:MANual).
MARKER:TYPe
This command specifies the marker type (either DELTa or ABS olute) to use when the automatic
markers for the frequency domain traces are turned on. To turn on the automatic markers,
use the command MARKER:PE AK:STATE.
RF:CLIPPing? Returns a boolean indicating whether the RF input is “clipping” due to input over/under-range
detection.
RF:DETECTionmethod:MODe This command specifies whether the R F detection within the oscilloscope occurs automatically
or manually. T he default is AUTO. If you set the detection method mode to MANual, you
are then able to use the related
RF:DETECTionmethod commands to specify detection
method options for the frequency dom ain traces (the options are
MINUSpeak, SAMple,
PLUSpeak and AVErage).
2-52 MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual
Command Groups
Table 2-37: RF Commands (cont.)
Item Description
RF:DETECTionmethod:
RF_AVErage
This command speci fies the detection method the oscilloscope should use when creating an
RF Average trace in the frequency domain. The Average trace displays the average of values
from multiple acquisitions at each trace point.
RF:DETECTionmethod:
RF_MAXHold
This command speci fies the detection method the oscilloscope should use when creating an
RF Max Hold trace in the frequency domain. The Max Hold trace displays the largest value
in all acquisition history at each trace point.
RF:DETECTionmethod:
RF_MINHold
This command speci fies the detection method the oscilloscope should use when creating an
RF Min Hold trace in the frequency domain. The Min Hold trace displays the smallest value
throughout the acquisition history at each trace point.
RF:DETECTionmethod:
RF_NORMal
This command specifies the detection method the oscilloscope should u se when creating
an RF Normal trace in the frequency domain. The N ormal trace displays the m ost recently
acquired sample at each trace point.
RF:FREQuency This command specifies the center frequency of the RF acquisition system. The center
frequency range varies with the model:
RF:LABel
This command specifies a general label for the RF frequency domain traces.
RF:MEASUre:ACPR:
ADJACENTPAIRs
When the R F measurement type has been set to ACPR, the frequency domain displays a Main
channel in the center (Ch:Main), and a side channel group on either side of the Main Channel.
There can be either 1, 2 or 3 channels w ithin each s ide group; this command specifies that
number. (Lower Area 1, 2 and 3 would be on the left side of the Main channel; Upper Area 1, 2
and 3 would be on the right side).
To set the measurement type to ACPR, use the command
RFMEASUre:TYPe ACPR.
RF:MEASUre:ACPR:CHANBW This command configures the measurement bandwidth to use for the Main channel, as well
as the adjacent side channels, when performing ACPR measurements using a frequency
domain trace. The RF measurement type must first be set to ACPR using the command
RFMEASUre:TYPe ACPR.
RF:MEASUre:ACPR:
CHANSPACing
This command specifies the center-to-center spacing between the Main channel and adjacent
channels when performing ACPR m easurements using a frequency domain trace. (The RF
measurement type must be set to ACPR using the command RF:MEASUre:TY Pe.) Note that
if the channel spacing is adjusted to be more narrow than the channel bandwidth, then the
oscilloscope will automatically decrease the channel bandwidth.
NOTE. The oscilloscope will maintain the span to fit all the channels
on-screen, plus a margin of 10% (5% on either side.)
RF:MEASUre:ACPR:LA1DB? This query measures a ratio between the first lower adjacent side channel and the Main channel
when performing ACPR m easurements. The power in the adjacent channel is equivalent to the
power in the main channel (dBm) added to the power ratio (dB) of the adjacent channel. (The
RF measurement type must be set to ACPR using the command RF:MEASUre:TYPe)
RF:MEASUre:ACPR:LA2DB?
This query measures a ratio between the second lower side channel and the Main channel
when performing ACPR measurements using a frequency domain trace. The power in the
adjacent channel is equivalent to the power in the main channel (dBm) added to the power
ratio (dB) of the adjacent channel. (The RF measurement type must be set to ACPR using
the command RF:MEASUre:TYPe)
MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual 2-53