Agilent Technologies Signal Analyzer N9030a User Manual

Page 596

6 RLC Swept SA Measurement Front-Panel & SCPI Reference
Input/Output

I/Q Path

Selects which I/Q input channels are active. The LED next to each I/Q input port will be on when
that port is active.

The analysis bandwidth for each channel is the same as that of the instrument. For example, the
base N9020A has a bandwidth of 10 MHz. With I/Q input the I and Q channels would each have
an analysis bandwidth of 10 MHz, giving 20 MHz of bandwidth when the I/Q Path is I+jQ. With
option B25, the available bandwidth becomes 25 MHz, giving 25 MHz each to I and Q and 50 MHz
to I+jQ.

I/Q voltage to power conversion processing is dependent on the I/Q Path selected.

•

With I+jQ input we know that the input signal may not be symmetrical about 0 Hz, because it

has a complex component. Therefore, above 0 Hz only the positive frequency information is
displayed, and below 0 Hz only the negative frequency information is displayed.

•

With all other Input Path selections, the input signal has no complex component and therefore

is always symmetrical about 0 Hz. In this case, by convention, the power conversion shows the
combined voltage for both the positive and negative frequencies. The information displayed
below 0 Hz is the mirror of the information displayed above 0 Hz. This results in a power
reading 6.02 dB higher (for both) than would be seen with only the positive frequency voltage.
Note also that, in this case the real signal may have complex modulation embedded in it, but
that must be recovered by further signal processing.

Key Path

Input/Output, I/Q

Remote Command

[:SENSe]:FEED:IQ:TYPE IQ|IONLy|QONLy|INDependent

[:SENSe]:FEED:IQ:TYPE?

Example

Set the input to be both the I and Q channels, combined as I + j * Q.

FEED:IQ:TYPE IQ

Notes

The Independent I and Q selection is only available in GPVSA

Preset

State Saved

Yes

This is unaffected by a Preset but is set to the default value on a "Restore Input/Output
Defaults" or "Restore System Defaults->All"

Range

I+jQ | I Only | Q Only | Independent I and Q

Readback Text

I+jQ | I Only | Q Only | Ind I/Q

Initial S/W Revision

Prior to A.02.00

Remote Command

:INPut[1]:IQ:TYPE IQ|I|Q

:INPut[1]:IQ:TYPE?

596

Remote Language Compatibility Measurement Application Reference