Rohde & Schwarz R&S SMU200A, Руководство по обслуживанию

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Test Procedures R&S SMU200A
1007.9845.82 1.66
E-12
Function External Data
The equipment layout for generating the digital modulation signals includes the options R&S B13 (Baseband
Main Module) and R&S B10 (Baseband Generator).
Test equipment Vector signal generator DUT (table 1-1, pos. 5) , Signal Analyzer R&S
FSQ with option R&S FSQ-K70 (Vector Signal Analysis) (table 1-1,
pos.24)
Test setup
Connect DATA and CLOCK outputs of reference DUT to DATA and
CLOCK inputs of test DUT.
Connect signal analyzer to RF output of DUT
Test method As described above (test of external clock), but now the data from the
external input is also taken.
Measurement Settings on test DUT
Frequency: 100 MHz
Level: 0 dBm
Custom Digital Mod:
State ON
Data Source External Serial
Modulation Type 8PSK
Symbol Rate 20MHz
Filter RRC (Root-Raised-Cosine)
Roll off 0.22
Clock Source: External
Global Settings
Threshold Data Input 50Ohm
Impedance Data Input 1.5 V
Settings on reference-DUT
Frequency: 100 MHz
Level: 0 dBm
Custom Digital Mod:
State ON
Data Source Pattern 01010101 11110111 00001000
Modulation Type 8PSK
Symbol Rate 20MHz
Filter RRC (Root-Raised-Cosine)
Roll off 0.22
Settings on analyzer:
VSA
FREQ CENTER: 100 MHz
AMPT / REF LEVEL 5 dBm
MODULATION SETTINGS
SYM RATE 20 MHz
MODULATION & MAPPING PSK 8PSK
MODULATION FILTER RRC RRC RRC RRC
ALPHA BT 0.22
Read out the data pattern of the demodulated signal and compare it
with the transmitted pattern. The data-pattern search function of the
R&S FSQ can be used for this purpose.
The number of necessary measurement depends on the number of installed RF- and baseband paths, see
following table:
Installed paths 1 x RF
1 x BB 2 x RF
2 x BB 2 x RF
1 x BB 1 x RF
2 x BB
Custom Digital Mod: external clock and external data
Number of measurements
1 x 1 x 1 x 1 x