Cell Broadcast Service (CBS)

Cell Broadcast Service (CBS) Overview

The Cell Broadcast Service in the test set allows you to send cell broadcast messages to the mobile station that are transmitted at a defined repetition interval (see Cell Broadcast Setup -General for more information). This allows the mobile station to receive the message even if entering the cell after the first transmission. The cell broadcast messages can be from one to fifteen pages in length, and are transmitted by the test set until the cell broadcast service is disabled or the state of the message(s) being transmitted is set to OFF. All messages sent from the test set are automatically segmented into the minimum number of pages possible. Cell broadcast messages contain a page parameter that indicates to the mobile station the number of the current page being received as well as the total number of pages in the message.

The test set can transmit up to three different messages at a time using the Cell Broadcast Service. If you configure the Cell Broadcast Service to transmit multiple messages, the messages are sent in sequential order at a rate of one page every multiframe until all the pages in the enabled messages are transmitted. The messages are retransmitted at specified intervals, which are set by the Repetition Period .

There are several message parameters that the test set allows you to set. It is important that you configure your mobile station to receive cell broadcast messages. This is done by enabling reception of messages in your mobile station and specifying the message parameters that it can receive, and set the parameters according to the type of cell broadcast message your mobile station is allow to receive. Cell broadcast messages are not acknowledged by the mobile station.

In addition to the pre-defined text strings, you can specify a custom text string and custom data to be sent in a cell broadcast message. See Cell Broadcast Messages -Content for more information on configuring the contents of the cell broadcast message.

Cell Broadcast Message Setup

All three of the messages available for use in the test set's Cell Broadcast Service can be configured independently. The content of each message can include either one of two predefined text messages, a custom text message or a custom binary/UCS2 message.

There are several configurable parameters for each cell broadcast message. The serial number is made up of three of these parameters: Geographical Scope, Message Code, and Update Number as shown in the diagram below. Refer to 3GPP 23.041 version 6.2.0 section 9.4.1.2.1 for more information about cell broadcast message parameters.

Additionally, each message is classified by topic and allocated a message identifier, data coding scheme, and message content. The following list contains all the configurable cell broadcast message parameters offered by the test set.

• State - allows you to configure which messages are sent using CBS. The message state must be ON for each message you want to send. The State for Message 1 is set to ON by default.

  The GPIB command for this parameter is CALL:SMService:CBRoadcast:MESSage[<n>]:STATe .

• Geographical Scope (GS)

  This parameter indicates the geographical area over which the message code is unique and the mode that should be used by the mobile station when displaying the cell broadcast message.

  The following list contains the settings available for the Geographical Scope parameter.

  • Cell Wide / Immediate (CIMMediate) - Similar messages received in any other cell is regarded as new. The immediate display setting indicates that the cell broadcast message is displayed on the mobile station at all times. This setting corresponds to a GSCOPE request URL equal to 0.
  • PLMN Wide / Normal (PNORmal)- The message code and/or update number must change in the next cell for the cell broadcast message to be considered new. The cell broadcast message is displayed on the mobile station only when the user wants to see it.This setting corresponds to a GSCOPE request URL equal to 1.
  • Location Area Wide/Normal (LNORmal) - The cell broadcast messages with the same message code and update number are considered new in the next cell only if the next cell is in a different location area than the current cell. The normal display mode displays the message only when the user wants to see it.This setting corresponds to a GSCOPE request URL equal to 2.
  • Cell Wide / Normal (CNORmal) - Similar messages received in any other cell is regarded as new. The normal display mode displays the message when the user wants to see it. This setting corresponds to a GSCOPE request URL equal to 3.

  The GPIB command for this parameter is CALL:SMService:CBRoadcast:MESSage[<n>]:GSCope .

• Message Code

  This parameter identifies a particular message, so that a mobile station receiving a message with the same code as a previously received message will recognize that it is a repeat, and may not display it to the user.

  The GPIB command for this parameter is CALL:SMService:CBRoadcast:MESSage[<n>]:CODE .

• Update Number

  This parameter is used to identify a particular version of a message. This is useful for reporting a dynamic situation, where a message may be reporting one event (such as road works or road construction ahead), but the details change periodically (the length of the tail-back or traffic jam caused, for example). A mobile station which remains in one cell for a length of time receives messages with the same message code but increments the update numbers as updated versions of the same message are received. A mobile station that has just entered a cell receives only the most recent version of the message, followed by any subsequent versions. The update number wraps from 15 to 0.

  The GPIB command for this parameter is CALL:SMService:CBRoadcast:MESSage[<n>]:UPDate .

• Message Identifier

  The parameter is a header number identifying the message topic (such as 'Weather Report' or 'Traffic Information').

  The GPIB command for this parameter is CALL:SMService:CBRoadcast:MESSage[<n>]:IDENtifier .

• Data Coding Scheme Specification

  This parameter indicates the method used to set the data coding scheme. The methods available are Language (see Data Coding Scheme Language ) and Value (see Data Coding Scheme Value ).

  The GPIB command to specify the which method is used is CALL:SMService:CBRoadcast:MESSage[<n>]:DCSCheme[:SPECify] .

• Data Coding Scheme Language

  This parameter sets the data coding scheme value associated with the indicated language. The data coding scheme indicates the intended handling of messages, the alphabet and coding of the message content, and the associated language of the text. Changing this parameter does not translate the text of a message, it is used to automatically configure the message's data coding scheme. This method is only appropriate for configuring text messages.

  Refer to 3GPP TS 23.038 version 6.1.0 Release 6 (section 5) for details about setting the CBS Data Coding Scheme.

  The GPIB command to specify the how the mobile station interprets the content of received text messages by specifying a language is CALL:SMService:CBRoadcast:MESSage[<n>]:DCSCheme:LANGuage .

• Data Coding Scheme Value

  This parameter sets the 8-bit data coding scheme value that indicates the intended handling of messages, the alphabet and coding of the message content, and the associated language of the text. Changing this parameter does not translate the text of a message, it is used to automatically configure the message's data coding scheme.

  Refer to 3GPP TS 23.038 version 6.1.0 Release 6 (section 5) for details about setting the CBS Data Coding Scheme.

  The GPIB command to specify the how the mobile station interprets the content of received text messages by specifying the data coding scheme value is CALL:SMService:CBRoadcast:MESSage[<n>]:DCSCheme:VALue .

• Content associates the message with the actual data to be sent by the test set. See Cell Broadcast Messages -Content for more specific information on the cell broadcast messages that can be sent from the test set.

  The GPIB command for this parameter is CALL:SMService:CBRoadcast:MESSage[<n>]:CONTent .

Cell Broadcast Setup -General

The settings for the parameters explained in this section apply to all cell broadcast messages.

• Repetition Period

  The repetition period determines how often the cell broadcast messages are transmitted. The repetition period is applied to all cell broadcast messages. The test set transmits the cell broadcast message(s) in their entirety before repeating the message(s). If all the messages are transmitted before the repetition period is complete, no messages are sent until the beginning of the next repetition period. Alternatively, if the repetition period is shorter than the time required to send all the enabled messages, the test set overrides the specified repetition period and begins retransmitting the messages only after is has completely transmitted all cell broadcast message(s). The two mechanisms provided to specify the repetition period are as follows. Note: Both mechanisms configure the same repetition period parameter in the test set.

  1. Specify the repetition period as an integer value in seconds.
  2. Specify a more precise repetition period as an integer value of the number of units multiplied by the minimum interval period, where a unit represents the value of the minimum interval of time it takes to transmit a single page of a message. According to 3GPP TS 23.041 version 6.2.0 section 9.3.8, the minimum repetition rate in UMTS is one page of a cell broadcast message every 1.883 seconds.

     For example, if you set the repetition period to 3 units, the actual repetition period is 5.649 seconds.

Cell Broadcast Messages -Content

Several Cell Broadcast Service (CBS) message options are available which allow you to choose or create messages to be sent. You can set the Content parameter to Text1 , Text2 , Custom Text, or Custom Data . See the sections below for more information about these settings.

Predefined Cell Broadcast Text Messages

User Defined Text Message (Custom Text)

User Defined Text Message (Custom Data)