Operating Manual 1302.6163.12 - 03 6.253
R&S ESU Remote Control – Description of Commands
TRACe Subsystem
Example: "TRAC:IQ:STAT ON"
'Enables acquisition of I/Q data
"TRAC:IQ:SET NORM,10MHz,32MHz,EXT,POS,0,4096"
'Measurement configuration:
'Filter type: Normal
'RBW: 10 MHz
'Sample Rate: 32 MHz
'Trigger Source: External
'Trigger Slope: Positive
'Pretrigger Samples: 0
'# of Samples: 4096
"FORMat REAL,32"
'Selects format of response data
"TRAC:IQ:DATA?"
'Starts measurement and reads results
Return value: The result values are scaled linear in unit Volt and correspond to the voltage at the
RF input of the instrument.
ASCII Format (FORMat ASCII):
In this case the command returns a comma separated list of the measured voltage values in floating
point format (Comma Separated Values = CSV). The number of values returned is 2 × number of
samples, the first half being the I-values, the second half the Q-values.
Binary Format (FORMat REAL,32):
In this case, the command returns binary data (Definite Length Block Data according to IEEE 488.2),
with the lists of I- and Q-data being arranged one after the other in 32 Bit IEEE 754 floating point data.
The scheme of the response string is as follows:
#44096<I-value1><I-value2>...<I-value512><Q-value1><Q-value2>...<Q-value512>
with
– #4: digits of the subsequent number of data bytes (4 in the example)
– 4096: number of subsequent data bytes (# of DataBytes, 4096 in the example)
– <I-value x>: 4-Byte-Floating Point I-value; max. 512k
– <Q-value y>: 4-Byte-Floating Point Q-value; max. 512k
The number of I- and Q-data can be calculated as follows:
# of I-data = # of Q-data = (# of DataBytes) / 8
The offset of Q-data in the output buffer can be calculated as follows:
Q-data offset = (# of DataBytes) / 2 + LengthIndicatiorDigit
with LengthIndicatorDigits being the number of digits of the length indicator including the '#'. In the
example above (#44096...) this results in a value of 6 for LengthIndicatorDigits and the offset for the
Q-data will result in 2048 + 6 = 2054.
With >512 k ≡ 524288 samples, the data is transmitted in logical blocks of 512k
values. See below.
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