Instrument Function
R&S
®
SMU200A
342Operating Manual 1007.9845.32 ─ 15
ated with the R&S mapping wizard. The mapping wizard (mapwiz) is a tool from Rohde
& Schwarz designed for editing modulation schemes (e.g. QPSK, 32QAM). Its main pur-
pose is the assignment of logical symbol numbers to constellation points and the selection
of modulation specific parameters. Beyond this it supports the creation of nearly any
arbitrarily chosen constellation diagram. The output of mapwiz is a mapping file
(*.vam) that can be imported on a R&S SMU. The program was developed on a 32-bit
Microsoft Windows platform under MATLAB. For more information, refer to the descrip-
tion "Introduction to "mapwiz" Mapping Editor" on the Rohde&Schwarz Internet page.
5.8.3.3 Coding - Custom Digital Mod
Modulation symbols are coded directly before I and Q values or frequency shifts are
assigned. Coding is thus directly related to modulation methods, which is the reason why
codings are not freely combinable with modulation methods. The following table shows
which of the coding combinations are available and defines the modulation types for
which the various coding procedures can be used.
In the notation used below an denotes the n-th input symbol and bn denotes the corre-
spondingly coded output symbol. Individual bits in the symbols from the LSB (least sig-
nificant bit) to the MSB (most significant bit) are denoted by a0n, a1n and so on. The
same applies to the output symbols.
Table 5-6: Permissible coding combinations for modulation symbols and modulation type
OFF Differ-
ential
Phase
Diff.
Diff.
+Gray
Gray GSM NADC,
PDC,
PHS,
TETRA,
APCO25
(PSK),
PWT
TFTS/
TETRA
INMARSAT,
ICO, WCDMA,
cdma2000
VDL (FSK)
ASK X X
X X
BPSK X X
X X
pi/2 DBPSK X
X
QPSK X X
X X
X
QPSK45°
Offset
X X
X X
X
Pi/4 QPSK X X
X
Pi/4 DQPSK X
X
X X
8PSK X X
X X
X
8PSK_EDGE X
Pi/8 D8PSK X
X
MSK X X
X X X
2FSK X X
X X X
4FSK X X
X X
X
16QAM X X X X X
Baseband Signal - Baseband Block
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