HD is the acronym for High Definition. HDTV, accordingly, stands for high-definition television, a technical standard providing significantly sharper images and much more details than the previous PAL standard. Technically speaking, HDTV means a higher vertical and horizontal resolution than Standard Definition Television (SDTV). Common HDTV image resolutions are 1280 x 720 pixels or 1920 x 1080 pixels. The first resolution e.g. uses 1,280 dots per line (horizontally) and 720 dots per column (vertically). The resolution of the PAL standard is 720 x 576. To create an optimal image from HDTV signals, the display must have a matching physical resolution. TV sets that cannot directly display HDTV signals but convert them into smaller pixel numbers („HD-Ready“) are still available.
The digital TV standard is often also called “DVB“, which stands for Digital Video Broadcast. In this context, the abbreviation “FTA“ is also used, meaning “Free To Air“ or “Free View“. FTA programmes are non-encrypted, free programmes. These terms are often found on digital receivers. In addition to TV reception, digital receivers also provide DVB radio programmes. Digital satellite receivers are sometimes also called “DVB-S“ receivers, where “S“ stands for “satellite“.
DVB-S2 is a development of the DVB-S standard, allowing the transmission of more channels in a better quality. Compared to DVB-S, the more efficient transmission method allows approx. 30 % more data to be transmitted. Since the high quality of HDTV requires a high data volume, DVB-S2 represents an optimal transmission standard for HD signals. DVB-S2 systems use the same transmission technology as DVB-S, i.e. that antenna, LNB and wiring do not need to replaced when upgrading the system. The receiver, however, uses a different technology. Any DVB-S2 receiver can also receive DVB-S stations, but DVB-S receivers cannot process DVB-S2 signals. The DVB extension “DVB-S2” has been available for some time now. It is also called “8PSK”, and it allows the transmission of even more channels or the transmission of existing channels at an enhanced quality. Reception of DVB-S2 requires specific receivers.
Most European countries encrypt (encode) their digitally broadcast channels. To receive such channels either a provider-specific receiver or a receiver with a Common Interface (CI) is required. CI receivers equipped with decoder modules and corresponding smart-cards can receive the programmes encrypted with most of the available encryption methods. External decoder boxes which were common with analogue systems are not compatible with digital TV.
CI receivers have 1 or 2 slots for decoder modules. Different modules are required depending on the country and the pay-TV provider. The CI receiver is hence only a platform which facilitates the usage of additional decoder modules. The reception of different pay-TV packages is only possible with CI receivers.
CI modules are sometime also referred to as „CA“ modules, whereby „CA“ stands for „Conditional Access“. When used together with the corresponding smart card (access card), the modules decode encrypted programmes. Some modules are only capable of decoding a single system (e.g. Viaccess), while others may be compatible with multiple systems. The CI module needs to be inserted into the Common Interface slot. Generally, each country or provider requires a different module. For further information please contact the programme providers.
Smartcards are available at specialist dealers or directly from the programme providers. Smartcards are usually subject to a charge and national regulations (residence, nationality) may apply.
The variety of digital TV and radio stations broadcast across Europe is not only high, but also subject to constant change. Any printed channel list will hence often be outdated by the time it is published. Major channels can usually be received without changes for long periods, but smaller-scale channels, often providing highly interesting programmes, are often launched and then disappear from the satellite rather quickly. There are numerous printed publications covering the topic of satellite TV. However, the Internet is usually more up-to-date. The websites www.lyngsat.com and www.satcodx.com list the channels available from all directly receivable satellites. These data can be put into the receiver‘s scan function so new channels can be received.
Terrestrial TV is also due to be converted from analogue to digital technology by the year 2010. However, the DTT network does not yet provide full coverage. Coverage is being widened all the time, but it is already clear that complete coverage of a country will not be possible. The desired reception of terrestrial digital TV signals with a small antenna stick at the back of the receiver can only be realised in the direct vicinity of the transmitters. The major disadvantage to clients is the range - national DTT will of course only be provided in the respective country. TV and radio stations of other countries cannot be expected to invest enormous sums into the broadcast of „foreign“ channels. Digital TV has almost become the standard in many national cable networks and can hence be received at many camp sites. This is not much of a benefit though, as the channel variety is much smaller than that available by satellite. The same problem of coverage that applies to DTT also exists here as well, as cable operators are not likely to feed foreign channels into their networks. Furthermore, DTT, DVB-C and DVB-S always require separate receivers which are different for each system. In principle, DTT and DVB-C cannot match the number of channels and the reception range available with digital satellite TV (DVB-S).
DVB-T2 is the successor of the DTT standard. The same principle as with the satellite transmission (DVB-S2) applies: Thanks to improved and more efficient transmission technology, more programmes can be transmitted per channel, and HDTV transmission is enabled. Also, the signal is more stable and reliable. DVB-T2 is not downward compatible with DVB-T, i.e. a conventional DTT device cannot process DVB-T2 signals, but DVB-T2 devices can usually process DTT signals. DVB-T2 is already established as transmission standard e.g. in Great Britain and France, but its launch in Germany is still to be determined.