The Brazilian Digital Terrestrial TV System (SBTVD) is based on the Japanese Integrated Services Digital Broadcasting – Terrestrial (ISDB-T) system. Transmission can use Multiple Frequency Networks (MFN) and Single Frequency Networks (SFN), allowing a single TV channel to cover a large area using the same frequency, which increases spectrum efficiency and signal reception quality of the TV.
However, this standard uses an adapted Transport Stream version, the 204-byte Broadcast Transport Stream (BTS), incompatible with most equipment used by other digital TV standards. This is the case of Digital Video Broadcasting (DVB), known as the European standard, which uses only 188 bytes. To solve this problem, a new method created at Unicamp allows converting Integrated Services Digital Broadcasting – Terrestrial transport packets to Digital Video Broadcasting (and vice versa) in a simple way and without loss of information.
The conversion is done in transport layer through a technology that converts the Broadcast Transport Stream packets into Transport Stream, discards the null packets, and then reconstructs the Transport Stream into Broadcast Transport Stream with the same original integrity. In this way, it is possible to distribute the Broadcast Transport Stream, save bandwidth, and allow the construction of wider Single Frequency Networks and a lower bit rate than the original Broadcast Transport Stream. Among several options, the invention can be applied in TV distribution systems via satellite, cable, optical fiber, direct terrestrial broadcasting, telecommunications systems, microwave links, internet, among others.
By making the Integrated Services Digital Broadcasting – Terrestrial and Digital Video Broadcasting transport layer compatible with the proposed technology, it is possible to reduce bandwidth and use the existing infrastructure of broadcasters. This technology benefits all countries that have adopted Integrated Services Digital Broadcasting – Terrestrial technology in the Asia, Latin America, and Africa.