Transport stream analyser in the RANGERNeo 2  field strength meter

April 29, 2014.

This tool allows the user to make a comprehensive analysis of the Transport Stream (TS) contained in a tuned signal. The signal received through any of the equipment inputs: TS-IN, RF, IP or Optical Fibre-RF, goes through the CAM module and through the terrestrial and satellite demodulators. Now, the transport stream (TS) is available for a detailed and deep analysis of the digital signal.

The TS is a very useful feature, since it ensures signal quality during deployment and operation of transmission systems such as radio, television and data systems. For the same reason it is an essential function for telecommunications regulators, who are watching the quality and integrity of transmissions.

It is an indispensable tool for many professionals involved in the generation and transmission of signals, like head-ends, distribution networks, broadcasting centres, signal reception systems or system installers in general, which require a deep analysis of the signal in a very compact and self-contained equipment.

It can also be an interesting feature of knowledge and detailed study of signal structure for colleges or training centres, research centres, etc.

This tool has three main functions:

  • Tables: It shows all the metadata carried in the corresponding PSI/SI tables in a tree diagram so user can deploy its content to the detail.
  • Bitrates: It shows the bitrate information for each program in real time, in a graphical way and also shows the percentage contribution of each one to the total TS.
  • Alarms: It shows a list of alarms that warn about any possible failure in the TS layer according to the three priority levels described in the TR 101 290 measurement guidelines by the DVB group.

Each function is detailed below.

Table Analyser

This function displays the TS tables as they are captured. The system shows the tables in a tree diagram for easy browsing with the joystick. All components and contents of tables can be consulted by deploying the nodes. So the user can analyse the tables and see in detail what is being transmitted and if the information is properly encapsulated. This tool requires detailed knowledge about the contents of these tables.

Below is a brief explanation of the main tables that can appear in the detection of a TS. For more details we recommend to consult the technical standard ETSI TR 101 211.

Transport Stream tables analysis in the HD RANGER 2 field strength meter
Transport Stream tables analysis in the HD RANGER 2 field strength meter

PSI (Program Specific Information) Tables: These tables are specified by the MPEG-2 standard worldwide. They are used by all the digital transmission standards. The TS analyzer detects all the PSI tables. PSI tables are:

  • PAT (Program Association Table).
  • PMT (Program Map Table).
  • NIT (Network Information Table).
  • CAT (Conditional Access Table).

SI (Service Information) Tables: These tables are specified by the standard used in the area or country (in this case DVB). These tables are more detailed and imply a higher level of information relating to the PSI tables. The TS analyzer detects the most important SI tables. Most important SI tables are:

  • NIT (Network Information Table).
  • BAT (Bouquet Association Table).
  • SDT (Service Description Table).
  • EIT (Event Information Table).
  • TDT (Time and Date Table).
  • TOT (Time Offset Table).

Bitrate Analyser

This function shows the TS bitrate in a graphical way, and also by numbers and percentage. A pie graph, which is updated in real time, shows the evolution of the bitrate distribution for each one of the services in the tuned multiplex. It also allows selecting any of the services to check its composition, which is also shown in bar graph.

Bitrate analysis of a Transport Stream in the HD RANGER 2 field strength meter
Bitrate analysis of a Transport Stream in the HD RANGER 2 field strength meter

This function allows the user to compare between television services and to check the bitrate used by each one. User can observe dynamically the variation that when changing the transmission content. Another use may be to identify the amount of null packets and therefore to know the amount of payload that the multiplex can still take..

Alarms

This tool monitors the TS. It is a dynamic tool as it displays in real time the evolution of the TS and the alarms that may occur. The priority levels of alarms are set according to the recommendations by technical standards TR 101 290.

Priority levels:

  • Priority 1: High level security parameters. These are alarms that make the TS vulnerable and avoid them to be received.

  • Priority 2: Medium level security parameters. The alarm in any of these parameters does not prevent the receiving but it is indicative of a possible problem.

  • Priority 3: Low level security parameters. These are parameters that are not harmful but are required for getting the most from the receiver capabilities.
Transport Stream monitoring and alarms managing accorgding to TR 101 290 in the HD RANGER 2 field strength meter
Transport Stream monitoring and alarms managing accorgding to TR 101 290
in the HD RANGER 2 field strength meter