Wegener UNITY 4600 User Manual page 18

U 4600 U ' M
NITY SER S ANUAL
Term
Automated The mechanism used when the U4600 is unable to acquire a valid transport stream, loses network
Recovery control or detects an invalid control stream, or is unable to deliver the required services using its
current settings. The unit automatically begins attempting operations under "backup" unit settings
(or Recovery)
stored in the presets table until it can return to normal operation or is stopped by local user
command.
Boot loader Software residing in non-writable zone of flash which executes at unit reset. It will verify and load the
preselected application.
CA See "Conditional Access".
Wegener's network control software that may be used to manage your U4600 as well as other
COMPEL
hardware.
Conditional Access Wegener's system for securing the transmitted transport stream from unauthorized access. It
features distribution of ciphered authorizing messages within a special PID. Upon deciphering in
secure processors within the IRD, these messages continuously update the IRD with the current
descrambling key.
DPI Digital Program Insert. A special message, borne in an MPEG PID associated with a particular
program, that signals the boundaries of ad avails.
DTMF Dual-Tone Multi-Frequency. Tone signaling system used by the legacy telephone system. Tone
pairs represented each of the keyboard items 0-9, *, and #. This system may be used to control
external cueing equipment.
DVB Digital Video Broadcast working group. This is a shorthand designation for a group of industry
standards that provide enhancements in the use of MPEG transport streams. (For example, one
DVB standard defined the standard way QPSK-modulated carriers would convey these streams
over satellite world-wide.)
E /N Energy-per-bit per Noise density-per-Hertz. This is a unitless ratio that expresses signal-to-noise
b 0
ratio in carrier transmission systems that convey digital data. A quality measurement for any such
system is the E
the "E
Ethernet The widely-used LAN technology specified by IEEE standard 802.3
IRD
Integrated Receiver-Decoder. A product which features a "receiver" to extract transport streams
from satellite-borne carriers and a companion "decoder" to decompress MPEG elementary streams
(from within said transport streams) in order to recreate the original audio/video/data signals. The
Unity 4600 is an IRD.
Keep-alives Simple COMPEL network messages, addressed to "all", bearing date and time.These are
transmitted regularly (every 5 seconds, for example) so that IRDs may quickly and continuously
(COMPEL)
verify their network connection.
KMS Key Management System. The sub-system within the Wegener Conditional Access system that
creates and ciphers the scrambling keys and then distributes them to the uplink UMX5010 and all
downlinked IRDs conveyed in a special PID within the transport stream.
LAN
Local area network. Your U4600 may be connected to an Ethernet LAN.
LCD Liquid crystal display. The front-panel screen on your U4600 is a liquid crystal display.
LED Light-emitting diode. The front-panel indicator lights on your U4600 are LEDs
Mbps, kbps or Msps Units of data transport rate - Megabits per second (1 million bits per second), kilobits per second (1
thousand bits per second), or million symbols per second (1 million symbols per second)
800032-01 Rev. F
Table 1.3:
/N needed to just convey the digital data within acceptable error rates. This is called
b 0
/N threshold".
b 0
Glossary of Terms
Definition
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