Rohde & Schwarz SMBV100A, Руководство пользователя

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Instrument Function
R&S
®
SMBV100A
262 Operating Manual 1407.6062.32 ─ 08
Sets the carrier/noise, signal/noise or signal/inerferer ratio.
Whether a configuration of C/N or S/N is enabled, depends on the selected "Display
Mode".
●
In "Carrier Reference Mode", this entry determines the RFI power and thus the power
of the output signal. It does not affect the power of the useful signal, i.e. the carrier
power remains constant.
●
In "Noise Reference Mode", this entry determines the power of the useful signal, i.e.
the carrier power. The RFI power remains constant.
●
The level of the noise signal which is derived from the entered C/N or S/N value is
displayed in the menu under "Noise Level". The value is displayed automatically in
the units of the useful signal.
●
The level of the useful signal is displayed in the menu under "Carrier Level" and can
also be changed there. The displayed value corresponds to the value in the "Level"
display field.
●
The level of the output signal is displayed under "Carrier Level + Noise".
If "Set Noise Level via E
b
/N
0
" is selected, the associated C/N or S/N value is displayed
here.
SCPI command:
​
[:
​
SOURce<hw>]:
​
AWGN:
​
CNRatio
​
on page 498
E
b
/N
0
- AWGN
(Additive Noise only)
Sets the ratio of bit energy to noise power density in "Additive Noise" mode.
●
In "Carrier Reference Mode", this entry determines the noise level and therefore also
the level of the output signal. It does not affect the level of the useful signal, i.e. the
carrier level is kept constant.
●
In "Noise Reference Mode", this entry determines the level of the useful signal, i.e.
the carrier level. the noise level is kept constant.
●
The level of the noise signal which is derived from the entered E
b
/N
0
value is displayed
under "Noise Level". The value is displayed automatically in the units of the useful
signal.
●
The level of the useful signal is displayed in the menu under "Carrier Level". The
displayed value corresponds to the value in the "Level" display field.
●
The level of the output signal is displayed under "Carrier Level + Noise".
If "Set Noise Level via C/N or S/N" is selected, the associated E
b
/N
0
value is displayed
here.
SCPI command:
​
[:
​
SOURce<hw>]:
​
AWGN:
​
ENRatio
​
on page 498
Carrier Level / Signal Level
(Additive Noise and CW Interferer)
The name of this parameter depends on the selected "Display Mode".
●
In "Carrier Reference Mode", this parametr sets the carrier level. This entry corre-
sponds to the level entered in the Level header.
The level of the noise signal which is derived from the entered C/N or S/N value is
displayed under "Noise Level". The value is displayed automatically in the units of
the useful signal.
Impairment of Digital I/Q Signal and Noise Generator - AWGN/IMP Block