Scalar Mixer Calibration
Scalar mixer calibration is the most accurate method of calibration applied to measurements of mixers in frequency offset mode.
The scalar mixer calibration requires OPEN, SHORT, and LOAD standards as well as external power meter (See Figure 62). The power meter connection and setup is described in section 8.8.
Figure 62 Scalar mixer calibration setup
The scalar mixer calibration allows the following measurements:
- reflection S11 and S22 parameters in vector form;
- transmission S21 and S12 parameters in scalar form.
The power meter can be connected either one port or both ports. If power meter was connected to port 1 than S21 transmission parameter will be calibrated. If power meter was connected to port 2 than S12 transmission parameter will be calibrated.
Before you start the calibration, perform the following settings: select active channel and set its parameters (frequency span, IF bandwidth, etc.), and define the calibration kit. Then enable the frequency offset mode and perform the port settings.
| Note | The scalar mixer calibration can be performed without frequency offset. You can enable the frequency offset mode later, during mixer measurements. In this case the basic frequency range should cover the frequency range of each port in offset mode. This procedure is convenient but less accurate as involves interpolation. | |
|---|---|---|
| To access the scalar mixer calibration menu, use the following softkeys: | |||
|---|---|---|---|
| Click Reflection Port 1 softkey. | |||
| Click Reflection Port 2 softkey. | |||
| Click Transmission softkey. | |||
| Click Power softkey. | |||
| Note | Power meter sensor can be connected to the port, as during zero setting the output signal of the port is turned off. | ||
| Connect the power meter to Port 1. Perform two measurements over two frequency ranges (Freq 1 and Freq 2). | |||
| To complete the calibration procedure, click Apply. | |||
| To clear the measurement results of the standards, click Cancel. | |||
| Note | You can check the calibration status in channel status bar (See table 18) or in trace status field (See Table 21) – SMC label. |