Classification of set top boxes
Card machine separation technology is the meaning that the digital television receiving equipment (machine) and CA smart card and software (card), both through an interface product (kcal or CAM card) to connect, TV and STB reserved the universal interface. Before inserting the CA smart card, the hardware and software of all TV and STB are the same, and the smart card to be inserted into a first and the CAM card can be inserted into the TV or set-top box, work out the corresponding program. Although on the surface due to the use of CAM card access increases the cost of the user, but because of the lack of CA bound to operators and manufacturers are brought to use and reduces the production cost, eventually brought to reduce user access cost. The rapid development of IP technology poses a great threat to digital TV, but in the short term, due to the cost of the network, the two can only coexist and can not be replaced. Channel, because they can not meet streaming services, so it is not a STB that combines DVB and IP. With the introduction and improvement of MPEG-II and MPEG-IV with double decoding chip, a set of DVB and IP in one of the end products will become a member of the family, it is connected with the display computer and other intelligent devices, family, family to meet information needs.
The selected chips are different, the hardware platform is different, and the other equipments and interfaces are different. This makes up a variety of STB. For example, in addition to the STB modem or a network card, constitutes a bidirectional function of set-top box; and hard disk constitutes a personal video recorder (PVR:Personal Video Recorder), of course, all of these needs with the set-top box software. On the same hardware platform, the set-top boxes of different applications can be formed by hosting different software, and the diversified STB meets the needs of different levels. Machine card separation and all-in-one machine is almost a natural pair. Large scale manufacturing TV not only improves the reliability of the product, but also reduce the production cost, and is the basis of large-scale manufacturing products are consistent, this is not only reflected in the hardware as well as software. Because of the diversity of software, manufacturers are unable to produce set-top boxes on a large scale like television sets. Therefore, to achieve scale manufacturing, CA is the first problem to be solved.
The narrow sense only include digital set-top box equipment, according to the standard can be divided into digital satellite set-top box (DVB-S), European standard digital terrestrial set-top box (DVB-T), GB terrestrial digital set-top box (DTMB), digital cable TV set-top box (DVB-C). It can be divided into one-way set-top boxes, two-way set-top boxes and IPTV set-top boxes according to functions.
