Rohde & Schwarz R&S SMW200A - Page 320

Configuring the Internal Baseband Source
R&S
®
SMW200A
320User Manual 1175.6632.02 ─ 30
2. Convert the values from the file SICO.txt into binary format consisting of 16-bit
signed integer numbers. The numeric range between –1.0 and +1.0 corresponds to
the modulation range of the waveform 16-bit D/A converter of -32767 to +32767.
+1.0 -> 32767 -> = 0x7FFF
0.0 -> 0 -> = 0x0000
-1.0 -> -32767 -> = 0x8001
The Figure 5-19 shows the calculation and conversion steps. The highlighted col-
umns contain the resulting I and Q values represented in Little endian format.
Figure 5-19: I and Q values calculation and conversion
3. Use an ASCII editor which is able to handle binary data. Create and add the follow-
ing mandatory tags before this binary data set can be further processed:
●
TYPE
●
CLOCK
●
LEVEL OFFS
An example of the SICO.wv file contents could be:
{TYPE: SMU-WV, 0}{CLOCK: 10e6}{LEVEL OFFS: 3.010300,0.000000}
0000FF7F8E27BB79 ... 72D8BB79
To simplify the example, the checksum is set to 0, i.e. the instrument does not eval-
uate a checksum.
Tip: The tags TYPE, CLOCK, LEVEL OFFS and WAVEFORM are mandatory for each
waveform. All other tags are optional and can be inserted after the TYPE tag in
arbitrary order.
4. Pack the binary data into a WAVEFORM tag with the described structure.
{WAVEFORM-Length: #I0Q0I1Q1I2Q2 ... InQn}
● Calculate the Length
Using the Arbitrary Waveform Generator (ARB)