User's Manual Part 2

Test Set Calibration – continued

DRAFT

Mar 2001

3-57

SCt4812T CDMA BTS Optimization/ATP

Calibrating Test Equipment

The calibrate test equipment function zeros the power measurement level

of the test equipment item that is to be used for TX calibration and audit.

If both a power meter and an analyzer are connected, only the power

meter is zeroed.

Use the Calibrate Test Equipment menu item from the Util menu to

calibrate test equipment. The test equipment must be selected before

calibration can begin. Follow the procedure in Table 3-25 to calibrate the

test equipment.

Prerequisites

Ensure the following prerequisites have been met before proceeding:

 Test equipment to be calibrated has been connected correctly for tests

that are to be run.

 Test equipment has been selected.

Table 3-25: Test Equipment Calibration

 Step Action

1 From the Util menu, select Calibrate Test Equipment.

A Directions window is displayed.

2 Follow the directions provided.

3 Click on Continue to close the Directions window.

A status report window is displayed.

4 Click on OK to close the status report window.

Calibrating Cables

The cable calibration function measures the loss (in dB) for the TX and

RX cables that are to be used for testing. A CDMA analyzer is used to

measure the loss of each cable configuration (TX cable configuration and

RX cable configuration). The cable calibration consists of the following:

 Measuring the loss of a short cable – This is required to compensate

for any measurement error of the analyzer. The short cable (used only

for the calibration process) is used in series with both the TX and RX

cable configuration when measuring. The measured loss of the short

cable is deducted from the measured loss of the TX and RX cable

configuration to determine the actual loss of the TX and RX cable

configurations. The result is then adjusted out of both the TX and RX

measurements to compensate for the measured loss.

 The short cable plus the RX cable configuration loss is measured –

The RX cable configuration normally consists only of a coax cable

with type-N connectors that is long enough to reach from the BTS RX

port of the test equipment.

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