Keysight Technologies N5171B EXG, Руководство пользователя

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Keysight EXG and MXG X-Series Signal Generators User’s Guide 345
Real–Time Noise—AWGN (Option 403)
Adding Real–Time Noise to a Dual ARB Waveform
Figure 13-3 Real Time I/Q Baseband AWGN - Noise Mux Menu Softkeys
E
b
/N
o
Adjustment Softkeys for Real Time I/Q Baseband AWGN
This feature allows the AWGN C/N to be set using the E
b
/N
o
(energy per bit over noise power
density at the receiver or signal to noise ratio per bit) form. This requires the carrier bit rate to be
known. Refer to Figure 13-4, “Eb/No Carrier Bit Equation.”
Figure 13-4 E
b
/N
o
Carrier Bit Equation
For details on each key, use key help
as described on
page 40
.
Mode > Dual ARB > Arb Setup >
Real-Time AWGN Setup > More
Enables diagnostic control of
additive noise, so that only the
noise, only the carrier, or the
sum of both the noise and the
carrier are output from the
internal baseband generator.
With the ALC
off , this feature
enables direct measurement of
the carrier or the noise
contributions independently
from the total power. The system
still behaves as if both the noise
and the carrier are present on
the output when it comes to
determining the Auto Modulation
Attenuation and the RMS level
for RMS Power Search.
Figure 13-6 on page 346
provides additional details on
these settings.
The Carrier Bit
Rate softkey is
only available
when the Carrier
to Noise softkey
is set to E
b
/N
o
.
C
N B
d
-----------
Eb
N0
-------


dB 10
10
bitRate
carrierBandwidth
------------------------------------------------


 
 
log +
 
 
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