Saluki S3602 Series, User Manual

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changed in high-accuracy measurement so as to reduce the switch repeatability error.
3) Connector repeatability error
Connector wear may result in electrical performance changes. Proper connection maintenance can help to reduce the connector
repeatability error.
7.5.3.
System Errors
System errors are caused by non-ideal hardware properties and may be repeatable (therefore, it can be predicted). It is assumed that
system errors do not change over time. System errors can be determined by calibration and eliminated by mathematical calculation in
measurement.
System errors cannot be fully eliminated. Due to limitations of the calibration process, some residual errors may exist after calibration,
mainly resulting from:

Non-ideal calibration standard;

Connector connection;

Interconnected cable;

Instrument.
All measurements are affected by the dynamic accuracy and frequency errors. For reflection measurement, relevant residual errors
include:

Effective direction;

Effective source matching;

Effective reflection tracking.
For transmission measurement, relevant residual errors include:

Crosstalk

Effective load matching;

Effective transmission measurement.
1) Direction errors
The directional coupler or bridge is used for reflection measurement. The coupling end of the ideal coupler can only output the
reflection signal to the receiver for measurement. Actually, a small number of incident signals will leak to the coupling port through the
main channel of the coupler, which may result in directional errors in measurement. Directional errors can be determined and reduced
in the following methods.

Connect the load to the measurement port during calibration and regard the load port free from reflection.

The output signal of the coupling port is the leakage error signal.

Reduce the directional error signals in reflection measurement.
2) Crosstalk errors
Ideally, only the transmission signal through the tested device can reach the receiver. Actually, a small number of signals reach the
receiver through other paths in the analyzer. Such signals are called crosstalk signals. Crosstalk errors can be determined and
reduced in the following methods.

Connect the loads to Port 1 and 2 at the same time during calibration.

The signal measured by the measurement receiver is the leakage signal of the analyzer.

Eliminate the crosstalk errors by means of error correction during transmission measurement.