If an instrument does not have real-time noise capabilities, the noise effect does not work. Option 403 is required for real-time noise to function.
This cell enables or disables adding real-time, non-repeating additive white gaussian noise (AWGN) to the carrier being modulated by the waveform being played.
On – enables the addition of Real-time Noise.
Off – disables the addition of Real-time Noise.
The application turns real-time noise off if present in the signal generator.
Range: –100
dB to 100 dB
Default: 0.0 dB
Enter or change the carrier to noise ratio, which is the ratio of carrier power to noise power (C/N). The carrier power is defined as the total modulated signal power before noise power is added. The noise power is the in-channel noise power. A positive value makes C larger than N.
Range: 0.001 to 125 MHz
Default: 1.0 Hz
Specify the bandwidth over which the noise power is integrated for calculating the carrier to noise ratio.
Range: 1 - 2
Default: 1
Displays the flat noise bandwidth for the applied real-time noise. (Read-only)
When Real-time Noise is enabled, the software sets the following default parameters:
RF Blanking: NONE
Oversample Ratio: 2
Noise Bandwidth Factor: 1
When the Sample Clock is < 50 MHz, the Noise Bandwidth Factor adjusts the RF flat noise bandwidth to be either at least 0.8 times the sample rate for a bandwidth factor of 1, or 1.6 times the sample rate if the bandwidth factor is 2.
When the Sample Clock is > 50 MHz, noise cannot be enabled if the Noise Bandwidth Factor is 2. Any oversampling in a waveform will effectively make the noise bandwidth be that many times wider than the signal bandwidth.
The Noise Bandwidth is calculated as follows:
The noise bandwidth is at least 0.8 * [ARB Sample Clock] * [Noise Bandwidth Factor]
This parameter is not available with all instrument model numbers and may be grayed out.
Range: 0.001 to 100 MHz
Default: 1.0 Hz
Set or change the the noise bandwidth (MHz).
This parameter is not available with all instrument model numbers and may be grayed out.