HP ESG-D Series, Руководство пользователя

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9-15
Specifications
HP ESG-D Series Signal Generators Specifications
Simultaneous Modulation
All modulation types may be simultaneously enabled, except FM with
Φ
M
, AM
with burst envelope, and wideband AM with I/Q. AM, FM and
Φ
M
can sum
simultaneous inputs from any two sources (Int, EXT 1, and EXT 2.) Any given
source (Int, EXT 1, or EXT 2) may only be routed to one activated modulation
type.
Level Accuracy with Digital Modulation
(With ALC On; relative to CW; with PRBS modulated data; if using I/Q inputs,
= 0.5 V
rms
nominal)
1
1. The optimum I/Q input level is = 0.5 V
rms
. I/Q drive affects EVM,
origin offset, spectral regrowth, and noise floor. Typically, level accuracy with
ALC on will be maintained with drive levels between 0.25 and 1.0 V
rms
.
π
/4 DQPSK or QPSK Formats:
(Relative to CW; with raised cosine or root raised cosine filter and
α ≥
0.35; with 10 kHz < symbol rate < 1 MHz; at RF frequency
> 25 MHz; power < maximum specified
−
3 dB)
±
0.15 dB
Constant Amplitude Formats
(FSK, GMSK, etc): No degradation in power level accuracy
Level Accuracy with ALC Off
1
:
(After power search is executed; relative to CW level with
ALC on; if external I/Q is enabled: = 0.5 V
rms
)
1. When applying external I/Q signals with ALC off, output level will vary
directly with I/Q input level. Power search is an internal calibration routine
used to set output power when ALC is off. The routine disables all
modulation inputs, adjusts output power while applying 0.5 V
rms
to the I/Q
modulator, then enables modulation.
±
0.5 dB, typical
I
2
Q
2
+
I
2
Q
2
+
I
2
Q
2
+