3 VMA Mode
3.1 Digital Demod Measurement
Format name Description
Log Mag (dB) Data is converted to decibel units and shown on a linear Y axis
Linear Mag (Abs
Value)
Magnitude of the data is shown on a linear Y axis
Real (I) Real part of data is shown on a linear Y axis
Imaginary (Q) Imaginary part of data is shown on linear Y axis
I-Q Real part of data is shown on horizontal axis, imaginary part is shown on vertical axis, Independent
variable (X axis) is normal to display
Constellation Same as I-Q, but for data with symbols defined, only the symbol points are shown as dots with no
connecting lines
Phase Phase of complex data is shown on Y axis
I-Eye Real part of data is shown with X axis segmented (generally into 2 symbol segments) and each
segment is overlaid to show signal crossings at symbol boundaries
Q-Eye Same as I-eye but imaginary part of data is shown
Group Delay Useful for frequency response and IQ Meas Time traces. Shows the derivative of phase response with
respect to frequency or time
Remote
Command
:DISPlay:DDEMod:WINDow[1]|2|…|6[:TRACe]:FORMat MLOG | MLINear | REAL |
IMAGinary | VECTor | CONStln | PHASe | IEYE | QEYE | GDELay
:DISPlay:DDEMod:WINDow[1]|2|…|6[:TRACe]:FORMat?
Example
:DISP:DDEM:WIND2:FORM MLOG
Sets the second window data format to Log Mag
:DISP:DDEM:WIND2:FORM?
Notes Real, Imaginary, I-Q, Constellation, I-Eye and Q-Eye are available for IQ Meas Time and IQ Ref Time
trace
Log Mag, Phase and Group Delay are available for Channel Frequency Response trace
Log Mag, Real and Imaginary are available for ccEVM vs Symbole trace
Preset Depends on trace
State Saved Yes
Range Log Mag (dB) | Linear Mag (Abs Value) | Real (I) (Lin) |Imaginary (Q) (Lin) | I-Q | Constellation | Phase | I-
Eye | Q-Eye | Group Delay
3.1.4 Amplitude
Activates the Amplitude menu and selects Reference Level or Reference Value as
the active function, depending on the measurement.
Some features in this menu apply to multiple measurements. Some other features
apply only to specific measurements and their controls are blanked or grayed-out in
measurements that do not support the feature.
Vector Modulation Analyzer Mode User's &Programmer's Reference 228
To Next Page
Loading...
Need help?
General
