PSI SI DVB-H

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What is PSI/SI in DVB-H:

PSI (Program Specific Information) consists of data enabling a decoder to demultiplex DVB-H services. It contains the following table: PAT, PMT, NIT, CAT SI provides information on DVB-H services carried by different multiplexes, it contains the following table: BAT, SDT, EIT, RST, TDT, TOT, ST


Is PSI/SI mandatory in DVB-H?

Yes, in order for cell phones to receive DVB-H programs, Timeslicing, MPE-FEC, PSI/SI and ESG are all needed. To get the DVB-H service correctly for the cell phone, server must insert the associated information into the TS stream, that is PSI and SI.


PSI/SI and receiver (cell phone)

When the cell phone starts to receive DVB-H program, it actually starts with receiving PSI/SI. They are in the table format, no encryption and directly built in the TS datagram.

From PSI/SI information, the cell phone knows the program list and the PID of each program in the received TS. After that the cell phone can start to receive the particular PID of the target program and ignore all PIDs of all other programs in the same TS.

DVB-H network layer

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PSI/SI and DVB network

A DVB network is uniquely identified by a network_id. A DVB network consist of one or more Transport Streams (TS), each carrying a multiplex and being transmitted by one or more DVB signals. Information about a DVB network is available within the NIT sub_table (identified by network_id). The NIT lists all multiplexes and DVB signals available within the DVB network. The NIT is carried within each DVB network.

PSI contains the following tables: PAT(Program Association Table):The PAT lists PIDs for all PMTs in the stream. TS Packets containing PAT information always have PID 0x0.

PMT(Program Map Table):contain information about programs. For each program, there is a PMT.

NIT(Network Information Table): provides information about the multiplexes and transport streams on a given network. Information about the current network uses table_id of 0x40, that about other networks uses table_id of 0x41

CAT(Conditional Access Table):This table is used for conditional access to the streams. This table provides association with EMM stream.


How a mobile TV receiver using PSI/SI table to find the first time-slicing bursts

more detail will be added


How a mobile TV receiver switch channels

channel switch request is initiated via a user interface. This causes a mobile broadcast receiver to switch from the first channel to the second channel. more detail will be added, e.g how PSI/SI control this