Real Time

Using the AC Builder Tool to generate the AC signal

AC signal is defined in ISDB-T standard and is used to convey additional information on modulating signal-transmission control or earthquake alarm information. The earthquake alarm information is transmitted using AC of the center Segment (segment No.0).

AC builder is a built-in tool, with which you can generate the AC bits easily. Below is the procedure of using the AC builder to generate the AC bits for ISDB-T/Tsb or ISDB-Tmm signals. It contains four steps:

Step 1: Locate and open the AC builder

Step 2: Configure the report(s) to be included in the AC signal

Step 3: Set the initial synchronization signal, mode, and segment number of current signal

Step 4: Generate the AC signal

Step 1: Locate and open the AC builder

1. Select the ISDB-T or ISDB-Tmm format under the Format menu in the menu bar.

   

   Using AC Builder in ISDB-T format requires N7623B-Mxx (ISDB-Tmm Advanced, ISDB-T enhancement) license. If this license is not installed in the connected instrument, the AC Builder can not be used to generate AC bits for ISDB-T waveform.  

2. In the ISDB-T settings or ISDB-Tmm segment settings table, first, in AC Setup cell select AC Builder Tool as AC Setup type, and then click on the in the right side of the AC cell to open the AC builder.

   

Step 2: Configure the report(s) to be included in the AC signal 

Take setting the Report1 in the figure below as an example. You can add a report or delete existing report(s) by clicking the Add Report or Delete Report button.  

1. In the Alarm column, click the drop down menu to select whether this is alarm in this report.  

2. In the Number of Frame column, enter the number of frames this report will be included in.

3. Click the Setting button in the setting column to configure the settings of the report.

   • If the Alarm is set to No, the setting dialog is as below. Then select the Signal type identification (B1~B3) and enter the ID of the broadcasters.

       

   • If the Alarm is set to Yes, the setting dialog is as below. Set the parameters in sequence.

     

     1. Select the Identification signal (B21~B23). The table below lists the description of the identification signal.

        B21~ B23	Description
        000	Earthquake alarm detailed information (Corresponding area) *
        001	Earthquake alarm detailed information (Non-corresponding area) **
        010	Test earthquake alarm detailed information (Corresponding area) *
        011	Test earthquake alarm detailed information (Non-corresponding area) *note 2

        Notes:

        * In this case, the certain area is included in the broadcasting area.

        ** In this case the certain area is not included in the broadcasting area.

     2. Click to set the current time and reference time in the time setting window.  

        

     3. Select the type of information (B55) and configure the corresponding information.

        • If B55 is set to “0”, the areas in which the alarm is given are represented by B56-B111 and Table 3-39 is displayed in the lower part of the setting dialog. Then select the area the alarm is given by clicking on the corresponding check box.

          

        • If B55 is set to “1”, the information about earthquake center is transmitted by B56-B11 and Table 3-40 is displayed in the lower part of the setting dialog. Then set the parameters according to the alarm information.  

          

Step 3: Set the initial synchronizing signal, mode, and segment number of current signal

1. Under Initial Synchronization, select the Synchronizing Signal under use.

2. Under Mode, select the Mode under use.

3. Under Segment, select the segment number included in the signal.

Step 4: Generate the AC signal

Click the Generate button in the right bottom of the AC Builder to generate the AC signal.