Adding Noise and Predistortions, and Impairing the Signal
R&S
®
SMBV100B
259User Manual 1178.4460.02 ─ 03
Figure 4-3: AWGN: Understanding the displayed information
1 = Bit Rate derived from the selected "Symbol Rate = 3.840 Msym/s"
2 = Selected Carrier/Noise Ratio
3 = Carrier Power = Status bar > Level = 30 dBm
4 = Noise Power calculated form the "Carrier Power" and the "Carrier/Noise Ratio" = -30 dBm - 10 dB =
-40 dBm
5 = Carrier+Noise Power = power at the RF output; i.e. the power a connected power meter would measure
6 = Noise Bandwidth = System Bandwidth*Minimum Noise/System Bandwidth Ratio = 3.840 MHz*3 =
11.520 MHz
Use the built-in graphical signal monitoring function of the instrument to display the sig-
nal characteristics in real-time, see "To observe the effect of enabled additive noise
(AWGN)" on page 425.
Application fields
Typically, the noise generator is required for the following tests:
●
In receiver sensibility tests with predefined SNR of the receiver, see "To configure
the AWGN for receiver sensibility tests with predefined SNR of the receiver"
on page 267
●
In bit-error or block-error measurements, depending on the set signal-to-noise ratio
(SNR)
●
Whenever a pure noise signal is required
4.1.3 AWGN Settings
The "AWGN" block provides access to the settings for the AWGN generator.
How to access and configure the "AWGN Settings"
1. Select "Block Diagram > AWGN".
Adding Noise to the Signal