Evaluating a Duplexer

• Overview

• Procedure

Other Measurement Examples

Overview

This section illustrates how to evaluate a duplexer (Tx center frequency: 1.88 GHz, Rx center frequency: 1.96 GHz).

Procedure

Here, the DUT is evaluated by following the steps described in table below.

1. Determine the Segment Sweep Conditions

A segment sweep is performed by following the sweep conditions shown in table below.

2. Create a Segment Sweep Table

Entries are made in the segment sweep table following the steps described below.

    1.   Display the segment table.

    2.   Enter the setup data in the segment sweep table.

In this step, the IF Bandwidth, power level, delay time, and sweep time are not entered segment by segment. By turning off the display of those parameters on the segment table, you can use, in each segment without making a change:

• the IF Bandwidth (preset value: 70 kHz) of the channel specified by using Avg > IF Bandwidth

• Power level (preset value: 0 dBm) of the channel specified by using Sweep Setup > Power

• Sweep delay time (preset value: 0 sec) of the channel specified by using Sweep Setup > Sweep Delay

• Sweep mode (preset value: Stepped mode) of the channel specified by using Sweep Setup > Sweep Mode

• Sweep time (preset value: Automatic) of the channel specified by using Sweep Setup > Sweep Time.

3. Select the Segment Sweep as the Sweep Type

The segment sweep is selected as the sweep type.

4. Execute the Calibration

In this step, a 2-port ECal module and 3-/4-port module installed in the E5071C are used to execute calibration on the three ports used in the measurement.

1. Connect the USB port of the 2-port ECal module and the USB port of the E5071C with a USB cable. The connection may be made while the unit is powered.

2. Load and execute the 3-/4-port ECal programs.
    

   Setup Description	Key Operation
   Opening the VBA Project Open dialog box	Macro Setup > Load Project
   Loading ECalAssistant.VBA	Select D:\Agilent\ECalAssistant.VBA and press the Open button.
   Executing the program	Macro Run

3.   The EcalAssistant (start) dialog box appears.
   
   
    

4.  Click Next to display the EcalAssistant (port/channel selection) dialog box.
   
   
    

5. Following the instructions in the dialog box, select the type of ECal, test ports, and the channel.
    

   Setup Description	Key Operation
   Select Ports
   ECal type: Full 3-port calibration	3 Port
   Test ports to be used for ECal: 1, 2, and 3	1, 2, 3
   Select Channel
   Channel on which ECal is to be executed: Channel 1	Channel: 1

6.  Click Next. The EcalAssistant (connection) dialog box appears. Select 3-port/Channel:1.
   
   
   
   Connecting the ECal module
   
   
    

7. Click Next. The calibration dialog box for Port 1-2 appears.
   
   
8. Click Measure to Calibrate Port 1-2 settings. After successful calibration of Port 1-2, a new dialog box appears.
   
   
9. Click Next. The dialog box for the calibration of port 1-3 appears.
   
   
10. Click Measure to Calibrate Port 1-3 settings. After successful calibration of Port 1-3, a new dialog box appears.
    
    

11. Click Next. The dialog box for the calibration of port 2-3 appears.
    
    
     

12. Click Measure to Calibrate Port 2-3 settings. After successful calibration of Port 2-3, a new dialog box appears.
    
    
     

13. The EcalAssistant (complete) dialog box appears. Click Done to terminate the calibration.

ECalAssistant (complete) dialog box

5. Connect the DUT

The DUT is connected to test ports 1, 2, and 3.

6. Define the Setup for Display

The setup for display is defined.

7. Execute the Measurement

A trigger is applied to execute the measurement.

8. Define the Setup for the Segment Display and Scale

The setup for the scale is defined.

 Measurement result (segment display: order base)

9. Analyze the Parameters

The parameters for the duplexer are determined.

    1.   Determine the insertion loss and 3-dB bandwidth for Tx.

The insertion loss (loss) in this example is -1.243 dB, and the 3-dB bandwidth (BW) is 85.53 MHz.

    2.   Determine the insertion loss and 3-dB bandwidth for the Rx.

The insertion loss (loss) in this example is -1.627 dB and the 3-dB bandwidth (BW) is 71.04 MHz.

    3.   Determine the isolation between Tx and Rx.

The isolation (response value of marker 1)  in this example is -6.612 dB.

    4.   Determine the return loss of Tx.

The return loss (response value of Marker 1)  in this example is 12.65 dB.

    5.   Determine the return loss of Rx.

       The return loss (response value of Marker 1)  in this example is 13.80 dB.

    6.   Turn on the marker table display.

Activating Marker Table

10. Define the Setup for a Limit Table

Follow the steps below to make entries in the limit table.

    1.   Display the limit table for Trace 1 (S13).

    2.   Enter the setup data in the limit table for trace 1.

Completed limit table for trace 1

    3.   Display the limit table for Trace 2 (S21).

    4.   Enter the setup data in the limit table for trace 2.

Completed limit table for trace 2

11. Execute the Limit Test

The limit test is executed.

    1.   Turn on the limit line and limit test for Trace 1.

    2.   Turn on the limit line and limit test for Trace 2.

    3.   Apply a trigger to execute the measurement.
 

Limit test results

    4.   Maximize the screen display of Trace 1 to examine its details.

Enlarged display of trace 1

    5.   Maximize the screen display of Trace 2 to examine its details.

Enlarged display of trace 2