Atec Rohde-Schwarz-SMU200A - Manual (Page 18)

Version 08.00, January 2012
18 Rohde & Schwarz R&S ® SMU200A Vector Signal Generator
I/Q modulation
I/Q modulator
Operating modes external wideband I/Q,
internal baseband I/Q
I offset, Q offset
setting range −10 % to +10 %
resolution 0.01 %
gain imbalance
setting range −1.0 dB to +1.0 dB
resolution 0.001 dB
quadrature offset
setting range −10° to +10°
I/Q impairments
resolution 0.01°
I/Q swap I and Q signals swapped on/off
External wideband I/Q
This type of modulation is possible only in path A.
input impedance 50 Ω
VSWR up to 50 MHz < 1.2
input voltage for full-scale input
q
2 2
i
+ = 0.5 V V V
I/Q inputs
minimum input voltage for ALC state: on 0.1 V
Modulation frequency range I/Q wideband: on 100 MHz
I/Q wideband: on
up to 50 MHz < 6 dB (typ.)
RF frequency response for entire
instrument in modulation bandwidth
up to 5 MHz < 1.0 dB (typ.)
Carrier leakage without input signal, referenced to
full-scale input
3
< −55 dBc, < −65 dBc (typ.)
measured with 16QAM, root cosine filter, α = 0.5, symbol rate 10 kHz
RMS value
f ≤ 200 MHz < 0.3 %
f > 200 MHz < (0.2 % + 0.1 % × f/GHz)
peak value
f ≤ 200 MHz < 0.6 %
Error vector
f > 200 MHz < (0.4 % + 0.2 % × f/GHz)
D
e
lta / dB
5
4
3
2
1
0
–1
– 2
– 3
– 4
– 5
Frequency offset from carrier / MHz
– 100 100 0 60 – 20 – 60 20 40 80 – 80 – 40
RF 850 MHz
RF 1900 MHz
RF 2200 MHz
Measured frequency response of external wideband I/Q modulation.
3 Value applies after 1 hour warm-up time and recalibration for 4 hours of operation and temperature variations of less than +5 °C.