Rohde & Schwarz FSWP Series - Page 156

Annex: Reference
R&S
®
FSWP
156User Manual 1177.5856.02 ─ 07
Element Description
Samples Contains the number of samples of the I/Q data. For multi-channel signals all chan-
nels have the same number of samples. One sample can be:
●
A complex number represented as a pair of I and Q values
●
A complex number represented as a pair of magnitude and phase values
●
A real number represented as a single real value
See also Format element.
Clock Contains the clock frequency in Hz, i.e. the sample rate of the I/Q data. A signal gen-
erator typically outputs the I/Q data at a rate that equals the clock frequency. If the
I/Q data was captured with a signal analyzer, the signal analyzer used the clock fre-
quency as the sample rate. The attribute unit must be set to "Hz".
Format Specifies how the binary data is saved in the I/Q data binary file (see
DataFilename element). Every sample must be in the same format. The format can
be one of the following:
●
complex: Complex number in cartesian format, i.e. I and Q values interleaved. I
and Q are unitless
●
real: Real number (unitless)
●
polar: Complex number in polar format, i.e. magnitude (unitless) and phase
(rad) values interleaved. Requires DataType = float32 or float64
DataType Specifies the binary format used for samples in the I/Q data binary file (see
DataFilename element and Chapter A.3.2, "I/Q Data Binary File", on page 158).
The following data types are allowed:
●
int8: 8 bit signed integer data
●
int16: 16 bit signed integer data
●
int32: 32 bit signed integer data
●
float32: 32 bit floating point data (IEEE 754)
●
float64: 64 bit floating point data (IEEE 754)
ScalingFactor Optional: describes how the binary data can be transformed into values in the unit
Volt. The binary I/Q data itself has no unit. To get an I/Q sample in the unit Volt the
saved samples have to be multiplied by the value of the ScalingFactor. For polar
data only the magnitude value has to be multiplied. For multi-channel signals the
ScalingFactor must be applied to all channels.
The attribute unit must be set to "V".
The ScalingFactor must be > 0. If the ScalingFactor element is not defined, a
value of 1 V is assumed.
NumberOfChan-
nels
Optional: specifies the number of channels, e.g. of a MIMO signal, contained in the
I/Q data binary file. For multi-channels, the I/Q samples of the channels are expected
to be interleaved within the I/Q data file (see Chapter A.3.2, "I/Q Data Binary File",
on page 158). If the NumberOfChannels element is not defined, one channel is
assumed.
DataFilename Contains the filename of the I/Q data binary file that is part of the iq-tar file.
It is recommended that the filename uses the following convention:
<xyz>.<Format>.<Channels>ch.<Type>
●
<xyz> = a valid Windows file name
●
<Format> = complex, polar or real (see Format element)
●
<Channels> = Number of channels (see NumberOfChannels element)
●
<Type> = float32, float64, int8, int16, int32 or int64 (see DataType element)
Examples:
●
xyz.complex.1ch.float32
●
xyz.polar.1ch.float64
●
xyz.real.1ch.int16
●
xyz.complex.16ch.int8
I/Q Data File Format (iq-tar)