What is DVB?
DVB, short for Digital Video Broadcasting, is a suite of internationally accepted open standards for digital television. DVB standards are maintained by the DVB Project, an industry consortium with more than 270 members, and they are published by a Joint Technical Committee (JTC) of European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU). The interaction of the DVB sub-standards is described in the DVB Cookbook (DVB-Cook).
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What is a CAM?
A conditional access module (CAM) is an electronic device, usually incorporating a slot for a smart card, which equips a DVB television or set-top box with the appropriate hardware facility to view conditional access content that has been encrypted using a conditional access system. They are normally used with direct broadcast satellite services, although the UK digital terrestrial pay TV supplier Top Up TV also uses CAMs.
Some encryption systems for which CAMs are available are Nagravision, Viaccess, Mediaguard, Irdeto, KeyFly and Conax. NDS Videoguard encryption, the preferred choice of Sky Digital can only be externally emulated by a Dragon brand cam. The NDS cam which the Sky viewing card ordinarily uses is built into the Sky Digibox thus not visible. Dragon and Matrix, two popular cams with satellite television enthusiasts are multicrypt meaning each is capable of handling more than one encryption system. Matrix is more likely to be used by a novice as it can be upgraded via the PC card port in a laptop personal computer whereas a Dragon cam update is done via separate programmer hardware.
The standard format for a CAM is a PC card which takes a smart card to authenticate, although CAMs with the 'smart card' burnt into memory can be found. In addition, CAM emulators exist for many systems, either providing an interface to allow the use of more than one type of card, or a card not designed for that receiver.
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Eutelsat W2 16 dgs East
Eutelsat W2 @ 16 dgs East is Offering a total of twenty-seven simultaneously-active transponders, the W2 satellite provides a fixed widebeam coverage, spanning Europe, North Africa and the Middle East, and a steerable coverage.
Ten channels can be individually configured for operation via either of the two coverages. The remaining channels are connected to the Widebeam, which on the downlink is more concentrated than the widebeam coverages of W1 and W3, offering enhanced capability for television and multimedia broadcasting.
The steerable coverage is positioned over the Indian Ocean for broadcasting digital television services to Mauritius and Reunion Island and includes a large part of south-eastern Africa.
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Hotbird Satellite @ 13 degrees East
HOT BIRD™
With a constellation of three satellites, the HOT BIRD™ family at 13 degrees East forms one of the largest broadcasting systems in Europe, delivering over 1000 television channels to more than 120 million TV homes in Europe, North Africa and the Middle East. In addition to broadcasting television services, the system provides over 600 radio stations, and multimedia services, over the same wide coverage area.
The HOT BIRD™ satellites provide full coverage of Europe and the Middle East, and also take in parts of Africa and Asia. This is the prime position in Europe for reception of consumer television and radio. A Superbeam enables Direct-To-Home reception in beam centre with antennae smaller than 70 cm and a Widebeam, with slightly larger antennas, offers reception throughout Europe, North Africa and as far East as Moscow and Dubai.
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What is an "LNB" ?
LNB (Low Noise Block Converter) The LNB, sometimes also called the LNC, is the receiving head that is positioned at the focal point of a parabolic dish antenna. It amplifies and converts the satellite signals, and prepares them for further processing by the satellite receiver. Generally the lower the noise figure given for an lnb, the better it will perform eg 0.3db is a good lnb, 0.7db is not so good.
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What is meant by "Elevation" ?
Elevation is the angle above the horizon, and is also expressed in terms of degrees. This is the angle by which the dish must be "tilted" in relation to the theoretical horizon, in order to position it precisely for the desired satellite.
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What is "DiSEqc" ?
DiSEqC ("Digital Satellite Equipment Control") Standard system used to control digital-enabled satellite installations. For instance, DiSEqC can effect switching between several satellite dishes, or can control more complex Multifeed installations (e.g. ASTRA and EUTELSAT), the positioning of a motorised dish, control of a multi-party installation (Multiswitch), etc. Several levels or versions of DiSEqC are available, offering a varying range of functions.
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What is "Conditional Access" ?
Conditional Access (CA)
Smartcard system controlling access to encrypted Pay-TV programmes. By means of this broadcasting technology, the data signal transmitted is made available only to a specific customer base, usually against payment of a fee. CA systems are differentiated between an embedded (fixed installation) CA solution and so called CA modules. In the case of the embedded solution, the CA system is integrated into the receiver, whereas in the case of the modular solution the required decoding system is inserted into the receiver in the form of a CA module, or CAM. Examples of encryption systems used in Europe include IRDETO, VIACCESS, Nagravision, Cryptoworks, Videoguard and CONAX.
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What is "Common Interface" ?
Common Interface (CI)
The Common Interface is a standardised uniform interface for Pay-TV decoders. This interface is used to enable a CA module (Conditional Access-Module) to be used with the DVB receiver in order to decode Pay-TV programmes. This means that it is not necessary to purchase a separate set-top box for each Pay-TV provider. When the need arises, the CA modules and corresponding smart cards are interchangeable, which means the receiver is completely flexible, and can be used for a variety of encryption systems. In the USA, it is a legal requirement to provide the Common Interface feature in boxes that are sold to customers. In Europe, too, the European Parliament intends to make this hardware component compulsory for receivers. The Common Interface ensures a freely competitive market for set-top boxes.
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What is meant by the "Footprint" of a satellite?
Footprint (signal reception area) This is the area on the earth's surface that is "covered" by the HF signal of a satellite. Within this area, the signal can be received readily and without problems by any suitable satellite dish antenna. The digital ASTRA satellites have a significantly higher broadcast power output than the earlier first-generation ASTRA satellites. This means that ASTRA digital programmes can be received throughout Europe, in excellent quality, even when using small dish sizes. In fact, the minimum required now for digital reception is a parabolic dish with a diameter of only 46 cm, or a square flat antenna of 47 cm. The latest satellites eg Astra 2D have steerable beams that can be pointed to a very narrow footprint making it necessary to have a very large dish to receive the signal if you are outside the footprint area.
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What does "FEC" mean ?
Forward Error Correction: data intended to correct errors are added to the digital broadcast signal. The aim of this is to recognise and correct typical errors that are likely to appear along the transmission path. This facilitates problem-free reception even under adverse weather conditions.
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What does "Polarity" Mean?
Polarization:
One frequency can be used two times by using two opposing polarizations, so that the two signals on the two identical frequencies are not affecting each other. This helps to virtually double the actual number of channels which can be transmitted.
One way of transmitting a signal is in linear polarization, the other by rotating polarization. For the latter, imagine the signal to be transmitted like a screw.
Therefore, there are two polarization modes:
"H" = Horizontal, and "V" = Vertical, for linear polarized signals
"R" = Righthand, and "L" = Lefthand, for rotating/turning signals
Note: In US sometimes the expression "reversed polarity" is in use
Often, rotating signals are used in C-Band, and linear signals in Ku-Band, but there are no rules to this. Mostly - but not always - nominally equal frequencies on different polarizations are a little bit off-set to each other to minimize any remaining influencies.
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What does "encrypted" channel mean?
In order to view an encrypted / encoded / scrambled channel you require a suitable viewing card and/or other special equipment such as a Cam and viewing card.
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What does "free to air" mean. ?
In contrast to Pay TV, FTA refers to all digital TV and radio programmes that can be received without payment, i.e. free of charge. This is also known as Free TV, or, in Germany, as FreiSAT programmes. FTA DVB receivers can receive only unencrypted, free-to-air DVB programmes.
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