CIMM's Set-Top Box Data Lexicon is a compilation of terms and definitions associated with Set-Top Box data and its measurement. This Word-A-Week column highlights a term and definition from the Lexicon to help forge a common language for Set-Top Box data usage and expedite the roll-out of the data for its many industry applications.
In a prior column we delineated the difference between Analog and Digital Set-Top Boxes. In this column we talk about Analog and Digital transmission signals. The Analog signal has been around for years. It has been our standard transmission of television since its inception. But the landscape has changed dramatically with new transmission capabilities that have opened up new possibilities in not only signal delivery but also signal return path. There was "Analog" but there is arguably no more powerfully generic term in the realm of Set-Top Box Data as "Digital"; Hardware has gone "Digital," Software has become "Digital." But what does this mean?
Digital capability is at the core of the existence of Set-Top Box data for a myriad of industry uses and Digital Compression is the road that took us to Digital capability. It is safe to say that without Digital capability there would be no Set-Top Box data at this time.
Here are terms and definitions related to Analog and Digital Signals and the advent of Digital technology via Digital Compression:
See also: Digital Cable, Digital Signal
CIMM DEFINITION : In telecommunications, analog refers to a transmission standard that uses variable frequencies and amplitudes of electrical impulses to emulate the audio waveform of sound. A traditional form of telecommunications transmission in a constant variable wave, rather than in packet-based (or digital) form. (Source: CableLabs)
2 : An older version of a TV signal or the Set-Top Box that transmits programs in the lowest television definition in use today - 480i format. Data is transmitted only in one direction - to the household or viewers. There is usually no "back channel" or "return path" transmission where data or usage is transmitted back to the headend or operator.
3 : A continuous electronic signal that carries information in the form of a continuously variable waves unlike digital signals which are made up of discrete pulses. (Source: Nielsen)
4 : Refers to the way cable broadcasts are transmitted directly from the television wall cable to the television. It is one method by which television signals are transmitted since Low Power TV stations still transmit analog signals.
5 : Type of cable signal that normally does not allow back channel. With a STB or DVR, return path data collection may become possible. (Source: TIVO)
NOTE - In addition to the lack of a return path, analog STBs provide no consistent mechanism for the download or execution of software and thus cannot provide any interactivity, including IPGs and EBIF. (Source: FourthWall Media). Therefore you can't serve a household targeted ad via an analog signal. (Source: Visible World).
See also: Analog Signal
CIMM DEFINITION : (1) In communications and computer technology, digital refers to a method of encoding information using a binary system made up of zeroes and ones. In communications technology this takes the form of two very different electrical voltages, several volts positive and negative, to represent the two values. This substantial difference in voltages for each state makes it unlikely that minor fluctuations in voltage due to electro-magnetic interference will change the way a signal is interpreted when received. (2) Information that is encoded into bits and bytes, or packets (0s and 1s, computer binary language). Generally perceived to be an advanced communication form offering clearer signals and increased transmission capacity. (Source: CableLabs)
See also: Digital Cable
CIMM DEFINITION : A signal that has a limited number of discrete states prior to transmission. This may be contrasted with an analog signal which varies in a continuous manner and may be said to have an infinite number of states. (Source: CableLabs)
CIMM DEFINITION : An engineering technique for converting a cable TV signal into a digital format which may then be processed in a manner that requires a smaller portion of spectrum for its transmission. This compressed format allows many channels to be carried in the bandwidth normally required for one signal. This format can also be easily stored and manipulated. (Source: CableLabs)
2 : An encoding process that saves storage space and enables more channels, networks and other content to be delivered to the Set-Top Box. An encoding / decoding process that minimizes data storage and transmission sizes in STB collection engines.
Please refer to the CIMM Lexicon online at http://www.cimm-us.org/lexicon.htm for additional information on these and other terms.