This subsystem controls system error correction and recording of correction data.
Command tree: [SENSe<Ch>:]CORRection
:CDATa
:CKIT (cal kit commands)
:COLLect (perform calibration)
:CONNection
:CATalog?
:DELete
:DATA
:PARameter?
:DATE
:EDELay
:AUTO
:DIELectric
:DISTance
:ELENgth
[:TIME]
:FACTory
[:STATe]
:LOSS
:FREQuency
:OFFSet
:DFComp
:POWer (power calibration commands)
:SSTate?
Program example: Calibration
Writes or reads system error correction data for a specific channel <Ch>, calibration method ([SENSe<Ch>:]CORRection:COLLect:METHod:DEFine), and port combination <Port1_no>, <Port2_no>. The setting command can be used to transfer user-defined correction data to the analyzer; the query returns the current correction data set. ASCII or block data can be transferred, depending on the selected data transfer format (FORMat[:DATA]).
The sweep must be stopped to transfer calibration data; see program example for [SENSe<Ch>:]CORRection:COLLect:SAVE:SELected:DEFault.
This command affects the active calibration of channel no. <Ch> or the factory calibration (if no channel calibration is active). For the factory calibration, the query form is allowed only (no change of factory calibration data).
For an overview of calibration methods and error terms refer to section Calibration Types.
<Ch>
Channel number of the calibrated channel. If unspecified the numeric suffix is set to 1.
Error term parameters
String parameters describing the different error terms, depending on the current calibration method; see table below. Each term contains one complex value (real and imaginary part) for each sweep point.
Range [def. unit]
The error terms are dimensionless complex numbers. The parameters must be transferred in full length and have the following meaning:
'DIRECTIVITY' – Directivity at port <port1_no> 'SRCMATCH' – Source match at port <port1_no> 'REFLTRACK' – Reflection tracking at port <port1_no> 'LOADMATCH' – Load match at <port2_no> 'TRANSTRACK' – Transmission tracking between port <port1_no> and <port2_no> 'G11' ... 'G22' – G matrix elements, referenced to <port1_no> (irrespective of the values of <port1_no> and <port2_no>) 'H11' ... 'H22' – H matrix elements, referenced to <port2_no> (irrespective of the values of <port1_no> and <port2_no>)
G and H Matrices
The 7-term calibration types named Txx (e.g. TOM, TRM, TRL, TNA) are based on a network analyzer with two ports i and j, each equipped with a test receiver and a reference receiver. The system errors are described in terms of two "error two-ports" PG and PH:
The error two-port PG is assigned to port i of the analyzer. Its transmission matrix G describes how the system errors modify the outgoing and incident waves at port i:
The error two-port PH is assigned to port j of the analyzer. Its transmission matrix H describes how the system errors modify the measured incident and outgoing waves at port j:
In the two equations above, a and b denote the waves at the calibrated reference plane i and j (e.g. the input and output of the 2-port DUT). The m waves are the raw measured waves of test port i and j. The subscripts "ref" and "test" refer to the reference and test receivers, respectively.
During the calibration the network analyzer acquires ratios of wave quantities, which leaves one of non-diagonal matrix elements of G or H as a free normalization factor. The network analyzer uses the normalization H21 = 1.
*RST value
– The analyzer provides a default calibration corresponding to a test setup which does not introduce any systematic errors; see [SENSe<Ch>:]CORRection:COLLect:SAVE:SELected:DEFault.
<port1_no>
Source port number.
<port2_no>
Load port number. If the error term is not related to the load port, a dummy number can be used; e.g. CORR:CDAT 'REFLTRACK', 1, 0
SCPI, Command Types
Device-specific, command or query
After a system error correction in one of the sweep types Power, Time, or CW Mode, the query returns two sets of correction data, corresponding to the fixed CW frequency and the CW frequency plus 1 Hz (minus 1 Hz if the CW frequency is equal to the maximum frequency of the analyzer).
Example:
See [SENSe<Ch>:]CORRection:COLLect:SAVE:SELected:DEFault.
Calibration type
Parameters in [SENSe<Ch>:]CORRection:COLLect:METHod:DEFine
Available error terms (depending on port numbers)
One-port normalization (reflection) using an open or a short standard
REFL, RSHort
'REFLTRACK'
Full one port
FOPort
'DIRECTIVITY', 'SRCMATCH', 'REFLTRACK'
Two-port normalization
FRTRans
'TRANSTRACK'
One path two port
OPTPort
'DIRECTIVITY', 'SRCMATCH', 'REFLTRACK', 'TRANSTRACK'
TOSM
'DIRECTIVITY', 'SRCMATCH', 'REFLTRACK', 'LOADMATCH', 'TRANSTRACK'
TOM, TRM, TRL, TNA
TOM | TRM | TRL | TNA
'DIRECTIVITY', 'SRCMATCH', 'REFLTRACK', 'LOADMATCH', 'TRANSTRACK' (for reading and writing) 'G11' ... 'G22' and 'H11', 'H12', 'H22' (for reading only; the 'H21' matrix elements are normalized to 1)