No. Satellite TV receiver refers to the electronic equipment that converts the output signal of satellite down converter LNB into audio and video signals or radio frequency signals.

1) headend

The front-end system is mainly composed of video and audio compression encoder and multiplexer. The main task of the front-end system is to digitally encode and compress TV signals, and use statistical multiplexing technology to transmit more programs on the limited satellite transponder frequency band. DTH compresses video and audio signals according to MPEG-2 standard, and can be transmitted on 27MHz repeater through dynamic statistical multiplexing technology. 0 TV programs.

2) Transmission and uplink system (uplink)

The transmission and uplink system includes communication equipment and uplink equipment from the front end to the uplink station. There are two main transmission modes: intermediate frequency transmission and digital baseband transmission.

3) satellite

DTH system adopts high-power direct broadcast satellite or communication satellite. Due to technical and cost reasons, some DTH systems use high-power communication satellites, and DTH companies in the United States and Canada use more suitable dedicated high-power direct broadcast satellites (DBS).

4) User Management System (SMS)

User management system is the heart of DTH system, which mainly completes the following functions: Bian Xiao recommended.

A. registering and managing user data.

B. purchasing and packaging procedures.

C. establish program charging standards and charge users.

D. market forecasting and marketing.

User management system is mainly composed of database management system of user information and program information and call center, which answers users' questions and provides various customer services.

5) Conditional Access System (CA)

Conditional access system has two main functions:

A. encrypt program data.

B. authorized procedures and users.

At present, the conditional access systems used in DTH systems in the world mainly include NDS in the United States, Irdeto in Israel, Via Access in France, Nagra Vision in Switzerland, etc.

The American Direct Television Company and Canada Star Choice Company, which adopt direct television technology, use NDS conditional access system. The Dish Network(Echostar) in the United States and Bell ExpressVu in Canada, which adopt Echostar technology, use Nagra Vission conditional access system.

6) User Receiving System (IRD)

DTH user receiving system consists of a small dish satellite receiving antenna (DISH), an integrated receiving decoder (IRD) and a smart card.

IRD is responsible for four main functions:

A. decoding program data stream and outputting it to TV.

B. Decrypt with the key in the smart card.

C. receiving and processing various user commands.

D. download and run various application software.

DTH IRD system is not a simple hardware device, but also includes an operating system and a large number of application software. At present, the more successful IRD operating system is Open TV. Dish Network Company of the United States has started to gradually upgrade users' IRD open TV system.