Center (Digital Input)

Center represents the center frequency associated with complex digital data coming from the Logic Analyzer. The default value is 0 Hz. If digital data represents complex data that has been converted to an intermediate frequency (IF) by a digital mixer, enter the IF here. If the digital data is real, the Center property is ignored.

The Center and Sample Rate properties establish the limits for the Center Frequency of a measurement as follows:

(real data)
Minimum Center Frequency = 0
Maximum Center Frequency = Sample Rate / 2.56

(complex data)
Minimum Center Frequency = Center - Sample Rate / 2.56
Maximum Center Frequency = Center + Sample Rate / 2.56

The Center Frequency of the measurement may be set to any value within these limits. The VSA mixes the incoming data with a complex local oscillator to make the change.

Whenever the Sample Rate or Center properties are changed, the Center Frequency of the measurement is reset to equal the Center property and the Span is reset to the maximum value determined by the Sample Rate.

Center is the same for all channels. Setting the value for any channel sets the same value on all other channels.