s_parameter

The s_parameter function of e_factory measure the RF S parameters of a device. Output data may be graphed, saved in a flat file or processed with user-written programs. Drivers are built in and interface with the instruments using GPIB and/or DAQ.

Interface Parameters:

The interface parameters are used for testing s parameters. Start Frequency is the sweep start frequency in gigahertz, Stop Frequency is the sweep stop frequency in gigahertz, Frequencies is a pull down choice of frequency resolution points for the test. Averaging will combine and average the results “averaging” times for reduced measurement noise, Delay will add mathematical delay to the signal to shift the time/phase response per user requirements. The Post Process Program is a user defined program that uses processes the frequency, magnitude and phase response for go/no-go acceptance, graphing, database population or any other function the user can define. Three program fields may be added to the .rfa file as in the following:

[s_param]

start_freq=2.0

stop_freq=18.0

post_process=/usr/local/bin/l_process

Triggering:

Measurements occur by selection of the Trigger button. In the Manual mode, one measurement is made (including the averaging). In the Continuous mode, measurements are taken as long as the trigger button is enabled.

Interface Menus:

File

Save Response: Write out frequency, magnitude and phase response to a user-defined file. This function is enabled only after data is collected.

Post Process: Execute post process program with response data. This function is enabled only after data is collected.

Exit: Return to main.

Display

Plot Magnitude: Call plotting program to plot/print magnitude-only response and define axis and scales.

Plot Phase: Call plotting program to plot/print phase-only response and define axis and scales.

Plot TDR: Call plotting program to plot/print TDR (Time Domain Response) and define axis and scales.

Plot Polar: Call plotting program to plot/print magnitude/phase response in polar coordinates and define axis and scales.

Calibrate

Off: Turn calibration off.

Response: Calibrate short for S11 or S22, though for S12 or S21. The calibration commences with menun selection (connect standard first)

Mode

Step: The program will call each frequency step individually (and lock if using a synthesizer).

Ramp: The program will trigger the ramp mode of the sweeper and sample the VNA data to collect all the data in one sweep.

Response

Magnitude: Plot magnitude in the user interface.

Phase: Plot phase in the user interface.

TDR: Plot TDR in the user interface.

Memory

Store: Save active response to memory locations 1 through 8.

Recall: Recall response memory to active response. Note that the user may plot or process this data normally (even without the DUT connected)

Interface Tabs:

Plot: Display user interface plots.

Parameters: Edit user interface plots parameters.