Agilent Technologies E4406A manual Selecting Baseband I/Q Inputs

Making Measurements

Using Baseband I/Q Inputs (Option B7C)

Selecting Baseband I/Q Inputs

Baseband I/Q measurements may be made with “unbalanced” inputs using either two connectors (I and Q), or with “balanced” inputs using four connectors (I, Q, I, and Q). A variety of high and low input impedances can be selected. This flexibility allows measurements to be made at a maximum number of diagnostic locations in the transmitter circuitry.

To use the Baseband I/Q inputs the instrument must be in BasicMode, or another compatible mode which can utilize the Baseband I/Q input ports. For modes that support Baseband I/Q, the inputs and measurement defaults are activated and visible when either I only, Q only, or I/Q is selected for Input Port in the Input menu. For modes which cannot support Baseband I/Q, the inputs and defaults are absent.

Selecting Baseband I/Q Input Connectors

Option B7C adds a softkey menu that lets you select I/Q inputs. This menu is located under the Input/Output front-panel key in the Input menu. To select an input connector press Input/Output, Input Port. Select the desired input connector(s) from the following choices displayed:

•RF - Press to select the 50 Ω "N" RF connector.

•I/Q - Select if using 2 connector “unbalanced” or 4 connector

“Balanced” I/Q cabling. Complete your selection by choosing the appropriate input impedance and connectors in the section “Selecting Baseband I/Q Inputs” on page 159.

•I Only - Select if using I and/or I input connectors. Complete your selection by choosing the appropriate input impedance and connectors in the section “Selecting Baseband I/Q Input Impedance” on page 164.

•Q Only - Select if using Q and/or Q input connectors. Complete your selection by choosing the appropriate input impedance and connectors in the section “Selecting Baseband I/Q Input Impedance” on page 164.

•50 MHz Ref - Select to view the 50 MHz CW calibration signal (signal level is approximately -25.0 dBm).

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