VIII. Glossary

8PSK 8-PSK is usually the highest order PSK constellation deployed. With more than
8 phases, the error-rate becomes too high and there are better, though more
complex, modulations available such as quadrature amplitude modulation (QAM).
Although any number of phases may be used, the fact that the constellation must
usually deal with binary data means that the number of symbols is usually a power
of 2 ? this allows an equal number of bits-per-symbol.
CAM Conditional Access Module is an electronic device, usually incorporating a slot
for a smart card, which equips an Integrated Digital 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 (DBS) services.
Composite Video Composite video is the format of an analog television (picture only) signal before
it is combined with a sound signal and modulated onto an RF carrier. Composite
video is often designated by the CVBS acronym, meaning "Color, Video, Blank
and Sync". In German (with PAL being a German invention by Telefunken's Walter
Bruch) the abbreviation FBAS (Farbe-Bild-Austastung-Synchron) means the same.
It is usually in standard formats such as NTSC, PAL, and SECAM. It is a composite
of three source signals called Y, U and V (together referred to as YUV) with sync
pulses. Y represents the brightness or luminance of the picture and includes
synchronizing pulses, so that by itself it could be displayed as a monochrome
picture. U and V represent hue and saturation or chrominance; between them they
carry the color information. They are first modulated on two orthogonal phases of
a color carrier signal to form a signal called the chrominance. Y and UV are then
combined. Since Y is a baseband signal and UV has been mixed with a carrier,
this addition is equivalent to frequency-division multiplexing.
Conditional Access System Several companies provide competing Conditional Access Systems; Irdeto
Access, Nagravision, Viaccess, Verimatrix and NDS are among the most
commonly used CAS systems.
DiSEqC Stands for Digital Satellite Equipment Control. It is a special communication
protocol for use between a satellite receiver and a device such as a multi-dish
switch or a small dish antenna rotor. DiSEqC was developed by European satellite
provider Eutelsat, which now acts as the standards agency for the protocol.
Dolby Digital Dolby Digital is the common version containing up to six discrete channels of
sound. The most elaborate mode in common usage involves five channels for
normal-range speakers (20 Hz ? 20,000 Hz) (right front, center, left front, right rear
and left rear) and one channel (20 Hz ? 120 Hz allotted audio) for the subwoofer
driven low-frequency effects. Mono and stereo modes are also supported. Dolby
Digitalsupports audio sample-rates up to 48 kHz.
* Dolby Digital
* D (an abbreviation for Dolby Digital, often combined with channel count;
for instance, D 2.0, D 5.1)
EPG Electronic Program Guide is a digital guide to scheduled broadcast television or
radio programs, typically displayed on-screen with functions allowing a viewer to
navigate, select, and discover content by time, title, channel, genre, etc. by use of
their remote control, a keyboard, or other input devices such as a phone keypad.
Content can also be scheduled for future recording by a personal video recorder
(PVR). The on-screen information may be delivered by a dedicated channel or
assembled by the receiving equipment from information sent by each program
channel.
eSATA A variant of SATA meant for external connectivity with the following characteristics:
* Minimum transmit potential: Range is 500?600 mV. * Minimum receive potential:
Range is 240?600 mV. * Identical protocol and logical signaling (link/transport-
layer and above), allowing native SATA devices to be deployed in external
enclosures with minimal modification.
FEC Stands for Forward Error Correction. This is a system of error control for data
transmission, whereby the sender adds redundant data to its messages, also
known as an error-correction code. This allows the receiver to detect and correct
errors (within some bound) without the need to ask the sender for additional data.
The advantages of forward error correction are that a back-channel is not required
and retransmission of data can often be avoided (at the cost of higher bandwidth
requirements, on average).
HDMI Stands for High-Definition Multimedia Interface. It is a compact audio/video
interface for transmitting uncompressed digital data. HDMI connects digital audio/
video sources?such as set-top boxes, Blu-ray Disc players, personal computers
(PCs), video game consoles (such as the PlayStation 3 and some models of Xbox
360), and AV receivers?to compatible digital audio devices, computer monitors,
and digital televisions. As an uncompressed connection, HDMI is independent of
the various digital television standards used by individual devices, such as ATSC
and DVB, as these are encapsulations of compressed MPEG video streams (which
can be decoded and output as an uncompressed video stream on HDMI).
LNB Stands for Low-Noise Block converter. This is the (receiving, or downlink) antenna
of what is commonly called the parabolic satellite dish commonly used for satellite
TV reception. The LNB is usually fixed on or in the satellite dish. The purpose of
the LNB is to take a wide block (or band) of relatively high frequencies, amplify
and convert them to similar signals carried at a much lower frequency (called
intermediate frequency or IF). These lower frequencies travel through cables
with much less attenuation of the signal, so there is much more signal left on the
satellite receiver end of the cable. It is also much easier and cheaper to design
electronic circuits to operate at these lower frequencies, rather than the very high
frequencies of satellite transmission.
PID Stands for Packet Identifier. This is a set of numbers identifying stream packets
contained within a single data stream
Polarization The orientation of the electrical and magnetic fields of a signal. Satellites use
mainly vertical and horizontal polarization.
S/PDIF Stands for Sony/Philips Digital Interconnect Format. A common use for the S/PDIF
interface is to carry compressed digital audio as defined by the standard IEC
61937. This mode is used to connect the output of a DVD player to a home theater
receiver that supports Dolby Digital or DTS surround sound. Another common
use is to carry uncompressed digital audio from a CD player to a receiver. This
specification also allows for the coupling of personal computer digital sound (if
equipped) via optical or coax to Dolby Digital or DTS capable receivers.
SCART A French-originated standard and associated 21-pin connector for connecting
audio-visual (AV) equipment together. SCART is one of the most common method
of connecting audio-visual equipment together. However, transferring analogue
standard-definition content, SCART is becoming obsolete with the introduction of
new digital standards such as HDMI, which can also carry high-definition content
and multichannel audio.
Smartcard A pocket-sized card with embedded Integrated Circuits which can process data.
It can receive input which is processed and delivered as an output. The card may
embed a hologram to avoid counterfeiting. It is used for accessing encrypted TV
channels or services.
Teletext A television information retrieval service developed in the United Kingdom in the
early 1970s. It offers a range of text-based information, typically including national,
international and sporting news, weather and TV schedules. Subtitle (or closed
captioning) information is also transmitted in the teletext signal, typically on page
888 or 777.
Xcrypt One of the Conditional Access Systems by Xcrypt.
YPbPr A color space used in video electronics, in particular in reference to component
video cables. YPbPr is the analog version of the YCBCR color space; the two are
numerically equivalent, but YPBPR is designed for use in analog systems whereas
YCBCR is intended for digital video.YPbPr is commonly called "component video",
but this is a misnomer, as there are many other types of component video (mostly
RGB with sync either on green or one or two separate signals).

YPbPr is converted from the RGB video signal, which is split into
three components, Y, PB, and PR.

* Y carries luma (brightness) and sync information.
* PB carries the difference between blue and luma (B - Y).
* PR carries the difference between red and luma (R - Y).
Sending a green signal would be redundant, as it can be derived using the blue,
red and luma information.