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Sensitivity Example

The Sensitivity example demonstrates using the Pulse Building GUI to create a signal with varying pulse power levels. The Sensitivity example also shows how to create a pattern within a pattern. One pattern, called Doublet, consists of two pattern items both of which are pulses. The two pulse types demonstrate pulse compression using Barker Code modulation. The other pattern, Sensitivity, consists of ten pattern items and each of these pattern items is a Doublet pattern. The Sensitivity pattern uses the Doublet pattern for all its pattern items.

This example demonstrates how to:

• Create pulses with modulation

• Build a pattern of patterns

• Use power scaling for pattern items  

Creating the Pulses

The following procedure steps through the process of creating the two Barker Code modulated pulse types.

1. Run the Pulse Building application.

2. Save this project. Use the File > Save As menu selection to save the project as Sensitivity.pbp.

3. Rename New Pulse 1 to BarkerA. Place the mouse pointer on the New Pulse 1 pulse, click the right mouse button, select Rename, and change the pulse name to BarkerA.

4. Enter the following information into the Pulse Library form:

   • Pulse Type: Raised-Cosine

   • Rise Time: 100 ns

   • Fall Time: 100 ns

   • Width (100%~100%): 800 ns

   • Width Jitter Type: None

   • Jitter Deviation: 0 s

   • Modulation Type: Barker

   • Code Length: 13

   The Pulse Library form below shows the configuration details for the BarkerA pulse.

   

5. Click the New Pulse icon in the Pulse Library form.

6. Rename New Pulse 1 to BarkerB. Place the mouse pointer on the New Pulse 1 pulse, click the right mouse button, select Rename, and change the pulse name to BarkerB.

7. Enter the following information into the Pulse Library form:

   • Pulse Type: Raised-Cosine

   • Rise Time: 100 ns

   • Fall Time: 100 ns

   • Width (100%~100%): 800 ns

   • Width Jitter Type: None

   • Jitter Deviation: 0 s

   • Modulation Type: Barker

   • Code Length: 7

The Pulse Library form will be identical to the BarkerA pulse shown above with the exception of code length and pulse name.

Creating the Patterns

There are now two pulses, BarkerA and BarkerB, stored in the Sensitivity Pulse Library. This section details the steps needed to create the first pattern, named Doublet, using these two pulses. Following sections describe how to use the Doublet pattern as a pattern item in the Sensitivity pattern.

1. Click the Pattern Library tab at the lower left corner of the Pulse Library form.

2. Click the icon.

3. Rename New Pattern 1 to Doublet

   • Click the mouse pointer on New Pattern 1 in the Patterns section of the form

   • Click the right mouse button

   • Select Rename from the menu and type in Doublet

4. Add a pattern item to the Doubletpattern. Click the icon once. The Pulse Building application automatically selects the first pulse from the Pulse Library. In this example the BarkerA pulse is selected.

5. Add a second pattern item to the Doublet pattern. Click the icon.

6. Select BarkerB for the Doublet pattern item at Index 2:

   • Click the mouse pointer in the cell located at the Index 2 row and Object Name column in the table

   • Click the down arrow in the drop-down list box of that cell

   • Select BarkerB

7. Enter the parameters and information as shown in the form below.

   

   • Index 1 - Object Name: BarkerA, Repetition Interval: 5 us, Repeat: 1, Edge Jitter Type: None

   • Index 2 - Object Name: BarkerB, Repetition Interval: 45 us, Repeat: 1, Edge Jitter Type: None, Power Scale: -20 dB,

     Phase Offset: 1.57 rad

The Doublet pattern now has two pulses, BarkerA and BarkerB, stored in the pulse building application's Pattern Library. The next section details the steps needed to create the Sensitivity pattern using the Doublet pattern as pattern items.

1. Click the icon.

2. Rename New Pattern 1 to Sensitivity.

   * Click the mouse pointer on New Pattern 1 in the Patterns section of the form

   * Click the right mouse button

   * Select Rename from the menu

   * Type in Sensitivity

3. Add pattern items to the Sensitivity pattern. Click the icon ten times.

4. Select a pattern as the object type:

   • Click the mouse pointer in the cell located at the Index 1 row and Object Type column in the table and select pattern.

   • Click the mouse pointer in the cell located at the Index 1 row and Object Name column in the table and select Doublet. This selection is the only pattern listed and it will be selected automatically.        

5. Position the mouse pointer in the tab section to the left of Index 1and then click the left mouse button. All item parameters for the row at Index 1 will be highlighted.  

6. Click the right mouse button and select Copy.

7. Position the mouse pointer in the tab section to the left of Index 2, click the right mouse button, and select Paste. The parameters copied from the item at Index 1 will be pasted to the item at Index 2.

8. Repeat the process in step 7 for the remaining index items.

9. Enter the Power Scale values as shown in the figure below.

10. Enter –10.00 in the Amplitude (dBm) text box

    

Download and Play

1. Click the Connect to Instrument button .

2. Enter LAN (TCP/IP) or GPIB interface parameters for the instrument in the System Configuration wizard.

3. Click the Test I/O Connection command button. The Status text box in the I/O Connection form should display: Connected.

   If errors or a timeout occurs refer to the troubleshooting section in the Help documentation or VISA documentation.

   

4. Click OK.

   If you do not have a spectrum/signal analyzer, you must disable the Auto-Correction routine. Go to Download > Correction Settings and remove the check mark from the Auto-Correction check box.

   If you are using a spectrum/signal analyzer, perform the following steps:

5. Click the Connect to Instrument button .

6. Enter LAN (TCP/IP) or GPIB interface parameters for the instrument in the System Configuration wizard.  

7. Click the Test I/O Connectioncommand button. The Status text box in the I/O Connection form should display: Connected

   If an error or a timeout occurs, refer to the troubleshooting section in this Help document or VISA documentation.

   

8. Click OK.

Click the Download menu item at the top of the form and select Download & Play. The lower section of the form, labeled VerifySignal Result: indicates the result of the signal creation and download process. 

At this point the signal, defined by the Sensitivity pattern, is loaded in the signal generator's volatile waveform memory and the signal generator is playing the signal. You can use the analyzer to view this signal. Use the following analyzer settings:

• Center Frequency: 15 GHz.

• Span: 200 MHz 

• Amplitude - Ref Level: Set the reference level to 10 dBm

• Trace View - select the Max Hold softkey to view the signal. 

You can save this waveform file in the signal generator's non-volatile waveform memory. When you save the waveform file, instrument state parameters configured in the Advanced settings section such as frequency and amplitude are not included. Use the signal generator's Save/Recall registers to save the signal generator's instrument state. When you want to re-load the signal and play it back:

1. Load the signal into volatile waveform memory.

2. Recall the register with the signal generator's instrument state associated with the waveform file.

Related Topics

Sensitivity API Program Example