Digital TV set-top boxes are capable of receiving MPEG-2 digital TV transport streams and a variety of data messages, viewing digital television programs and various data messages on analogue color televisions through demodulation, demultiplexing, decoding and AV encoding.
The basic function of a digital TV set-top box is to receive digital television broadcasts, as well as all broadcast and interactive multimedia applications including:
(1) Electronic Program Guide: It provides users with an easy to use, the interface is very friendly, you can quickly access the way you want to see the show, the user can see through this feature will be broadcast on each channel television programs.
(2) support for interactive applications such as video on demand, video on demand, interactive games.
(3) high-speed data broadcasting: to provide users with stock market information, ticketing information, electronic newspapers, popular network and other information.
(4) Internet access and e-mail: Digital TV set-top boxes enable Internet access through a built-in cable modem. Users can surf the Net through set-top box browser, send e-mail, can also provide a variety of interfaces connected with the PC, using the PC to access the Internet.
(5) software online upgrade: can be regarded as one of the applications of data broadcasting. The data broadcast server transmits the upgrade software to the set-top box. The set-top box can identify the version number of the software, receive the software when the version is different, and update the software saved in the memory.
(6) conditional access: the core of conditional access is scrambling and encryption, digital TV set-top boxes should have descrambling and decryption capabilities.