Virtual channel
In telecommunications, a logical channel number (LCN), also known as virtual channel, is a channel
Channel (communications)
In telecommunications and computer networking, a communication channel, or channel, refers either to a physical transmission medium such as a wire, or to a logical connection over a multiplexed medium such as a radio channel...

 designation which differs from that of the actual radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...

 channel (or range of frequencies
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...

) on which the signal travels.

The term is most often applied to television, where digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...

 (DTV) channels may operate on different physical channels from the displayed channels. A station branded as Channel 8, for example, might actually use channel 32 for its ATSC, DVB or ISDB
Integrated Services Digital Broadcasting is a Japanese standard for digital television and digital radio used by the country's radio and television stations. ISDB replaced the previously used MUSE "Hi-vision" analogue HDTV system...

 transmission, but a virtual channel map or virtual channel table (VCT) allows viewers to tune in the station on channel 8, displayed as 8.1 on a digital set. DTV tuners have a menu item that scans all channels for this information and stores it in memory for instant access later on.

The most common reason for a television station using a virtual channel is to minimize viewer confusion when a digital transmission is airing on a different channel from the one the station used in analog mode. The virtual channel thus enables viewers to tune in the station by choosing the same channel number as they would have previously.

Digital TV subchannels

Because DTV can carry multiple programs simultaneously
The multiplexed signal is transmitted over a communication channel, which may be a physical transmission medium. The multiplexing divides the capacity of the low-level communication channel into several higher-level logical channels, one for each message signal or data stream to be transferred...

, virtual channels also map out subchannels.

North America

Continuing the "Channel 8" example, if the station were in the United States and Canada, typically its main programming would air on channel 8 (the "major channel") or 8.1 (the first "subchannel"). Other programs could be found on channels 8.2, 8.3, and so forth, up to 8.99, with additional data channels ranging from 8.100 to 8.999. The subchannels can also be represented using a hyphen (8-1, 8-2, and so forth). There is no practical difference between the dot and hyphen forms, although the dot form is more familiar to FM radio
FM broadcasting
FM broadcasting is a broadcasting technology pioneered by Edwin Howard Armstrong which uses frequency modulation to provide high-fidelity sound over broadcast radio. The term "FM band" describes the "frequency band in which FM is used for broadcasting"...

 listeners, and avoids confusion with ranges of values (for example, 2-4 may be misinterpreted as the range 2 to 4 instead of the multiplex 4 of channel 2). A dot is also easier to display on LED
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

s in most set-top box
Set-top box
A set-top box or set-top unit is an information appliance device that generally contains a tuner and connects to a television set and an external source of signal, turning the signal into content which is then displayed on the television screen or other display device.-History:Before the...

es, as it need not occupy a full digit position.

Traditionally, most stations in the United States have adopted either their former analog channel for the virtual channel, or their actual digital channel position if they signed on as a digital station without having an analog station beforehand. There are a few rare exceptions; for instance, New York City's WNYZ-LP, which broadcasts on channel 6 in digital, uses the virtual channel 1.1, instead of 6.

The assignment of virtual channels in the United States is defined by ATSC document "A/65", Annex B. Rules for assignment of major channel numbers are as follows:
  • Existing analog stations were assigned a major channel number matching their existing analog number
  • New digital stations assigned to a channel whose matching major channel number is not in use must use that number
  • New digital stations assigned to a channel whose matching major channel number is in use (by a former analog station) must reciprocate, using the major channel number that matches the actual channel of the station in question

These rules guarantee that no overlapping will occur. Additionally, stations may apply for a license to broadcast some of their subchannels under a secondary major channel in the 70-99 range; these numbers are certain to be unused, as 69 was the highest assigned channel prior to the conversion to digital broadcasting. The document does not address the use of certain other major channel numbers:
  • Numbers below 70 that were never used in NTSC (0,1, and 37
    Channel 37
    Channel 37 is an unused television channel in countries using the M and N broadcast television system standards. Channel 37 occupies a band of UHF frequencies from 608 to 614 MHz, frequencies that are particularly important to radio astronomy...

  • The real numbers of stations that are using virtual channels from 53-69 (these stations are not covered by the reciprocity rule, as real station numbers are not assigned above 52)
  • Numbers in the range of 53-69 that are not being used by a former analog station

Additionally, broadcasters owning more than one station that overlap in coverage area may set all of the channels to use the major channel of just one of the stations, so long as different minor channel numbers are used to avoid overlap.


In Australia, allocation of logical channel numbers is governed by guidelines set by the commercial broadcasters' association, Free TV Australia.

LCNs in Australia may have one, two or three digits. Each network is allocated LCNs starting with a certain prefix - for instance, all metropolitan Nine Network
Nine Network
The Nine Network , is an Australian television network with headquarters based in Willoughby, a suburb located on the North Shore of Sydney. For 50 years since television's inception in Australia, between 1956 and 2006, it was the most watched television network in Australia...

 services use LCNs beginning with the digit '9'. Generally, but not always, the single digit LCN is allocated to the primary SD service (Network Ten
Network Ten
Network Ten , is one of Australia's three major commercial television networks. Owned-and-operated stations can be found in Sydney, Melbourne, Brisbane, Adelaide and Perth, while affiliates extend the network to cover most of the country...

's HD sub-channel One being the main exception). LCNs need not be contiguous, and a channel may be identified by more than one LCN. For instance, ABC Television
ABC Television
ABC Television is a service of the Australian Broadcasting Corporation launched in 1956. As a public broadcasting broadcaster, the ABC provides four non-commercial channels within Australia, and a partially advertising-funded satellite channel overseas....

's primary ABC1
ABC1 was a United Kingdom based television channel from Disney using the branding of the Disney owned American network, ABC.The channel initially launched exclusively on the British digital terrestrial television platform Freeview on 27 September 2004. On 10 December 2004 it was launched on...

 service is allocated LCNs 2 and 21; the latter allows it to be easily accessed amongst other ABC services which lie in the 21-24 range.

Regional affiliates of the three metropolitan networks are provided with a different LCN prefix. For instance, channels owned by affiliates of the Nine Network (in this case, WIN Television
WIN Television
WIN Television is an Australian television network owned by the WIN Corporation that is based in Wollongong, New South Wales. WIN commenced transmissions on 18 March 1962 as a single Wollongong-only station, and has since expanded to 24 owned-and-operated stations with transmissions covering a...

 and NBN Television
NBN Television
NBN Television is a television station based in Newcastle, New South Wales, Australia. The station was inaugurated on 4 March 1962 as the first regional commercial television station in New South Wales, and has since expanded to 39 transmitters throughout the northern half of New South Wales and...

) are prefixed with the digit '8' rather than '9'. This allows areas that are part of both a metropolitan market and a regional market, such as the Gold Coast
Gold Coast, Queensland
Gold Coast is a coastal city of Australia located in South East Queensland, 94km south of the state capital Brisbane. With a population approximately 540,000 in 2010, it is the second most populous city in the state, the sixth most populous city in the country, and also the most populous...

, Sunshine Coast
Sunshine Coast, Queensland
The Sunshine Coast is an urban area in South East Queensland, north of the state capital of Brisbane on the Pacific Ocean coastline. Although it does not have a central business district, by population it ranks as the 10th largest metropolis in Australia and the third largest in...

 and Central Coast, to receive all local commercial services. The ABC and SBS
Special Broadcasting Service
The Special Broadcasting Service is a hybrid-funded Australian public broadcasting radio and television network. The stated purpose of SBS is "to provide multilingual and multicultural radio and television services that inform, educate and entertain all Australians and, in doing so, reflect...

 use the same prefix in all areas.

Prefixes for remote-area services are intended to be overlaid over this model. When digital transmission starts in these areas, services licensed for the Remote Central and Eastern Australia licence area (Imparja
Imparja Television
Imparja Television is an Australian television network servicing remote eastern and central Australia, that began broadcasting on 2 January 1988. It is based in Alice Springs, where it has a studio and satellite uplink facility. Notably, it is controlled by Australian Aborigines through ownership...

 and Southern Cross Central
QQQ is an Australian television station broadcasting in remote eastern, southern and central areas of Australia.QQQ may also refer to:* QQQ , a fictional character in the F-Zero video game series...

) have been reserved the "metropolitan" prefixes corresponding to their affiliation; those in Remote Western Australia (GWN
Golden West Network
GWN7 is an Australian television network owned by the Prime Media Group that is based in Bunbury, Western Australia. The Golden West Network launched on 10 March 1967 as BTW-3 in Bunbury, and has since expanded to cover regional and remote Western Australia, servicing all areas except metropolitan...

 and WIN WA
WOW (TV station)
WOW is an Australian television station licensed to WIN Television, serving regional and remote Western Australia. The station officially commenced transmissions on 26 March 1999 as the second commercial regional broadcaster in Western Australia, alongside former monopoly, Golden West Network...

) the "regional" prefixes.

A number of LCNs are reserved for various reasons:
  • LCN 4 was originally intended for a free-to-air video program guide. In practice, the LCN 4 prefix has for most of its life been largely unused, except in Sydney (where it was used by the Digital Forty Four
    Digital Forty Four
    Digital Forty Four was a Sydney-only trial datacasting service which was licensed by the Australian Broadcasting Authority in March 2004 for an initial three year run until late 2007...

     trial datacasting service from 2004-2010). As of 2010, capital city community television stations (or "Channel 31" stations, after their typical analogue channel position) have begun to air in digital using LCN 44; one of which (West TV
    West TV
    West TV or WTV, previously New Visions 31, is a free-to-air community television station that began broadcasting in standard definition digital format on logical channel 44 in Perth on 10 April 2010 at 10 am.-History:...

     in Perth) airs exclusively via digital transmission.
  • The LCN range 350-399 is intended to be allocated by receivers to channels which either duplicate a stronger signal's LCN, or are transmitted without an LCN. For instance, if two broadcasts of LCN 2 were found, one signal (generally the stronger) will be allocated to LCN 2, and the weaker should be allocated to, say, LCN 350.
  • The LCN range 450-499 is intended for use by trial services by non-broadcasters.

Europe, Africa and the Middle East

In Europe, Africa and the Middle East, there is no special numbering system for subchannels; two related "channels" (that is, programme streams) may have completely unrelated numbers (for example, in the UK, ITV
ITV is the major commercial public service TV network in the United Kingdom. Launched in 1955 under the auspices of the Independent Television Authority to provide competition to the BBC, it is also the oldest commercial network in the UK...

 is channel 3 and ITV2
ITV2 is a 24 hour, free-to-air entertainment television channel in the United Kingdom owned by ITV Digital Channels Ltd, a division of ITV plc. It was launched on 7 December 1998, and is available on digital television via satellite, cable, IPTV and terrestrial platforms. The channel has the...

 channel 6, on Freeview).

In continental and eastern Europe, virtual channels are not used, since television sets and receivers there allow users to freely assign arbitrary "programme numbers" or "programme letters" to channels.

Stations still market themselves as "first", "second", or "third" channel (and so on), or "channel A", "channel B" or "channel C", etc., but this reflects the programme number at which the channel should be stored, not the RF channel used for transmitting the signals.

Virtual channels are also used on direct broadcast satellite
Direct broadcast satellite
Direct broadcast satellite is a term used to refer to satellite television broadcasts intended for home reception.A designation broader than DBS would be direct-to-home signals, or DTH. This has initially distinguished the transmissions directly intended for home viewers from cable television...

s, such as Dish Network
Dish Network
Dish Network Corporation is the second largest pay TV provider in the United States, providing direct broadcast satellite service—including satellite television, audio programming, and interactive television services—to 14.337 million commercial and residential customers in the United States. Dish...

, DirecTV
DirecTV is an American direct broadcast satellite service provider and broadcaster based in El Segundo, California. Its satellite service, launched on June 17, 1994, transmits digital satellite television and audio to households in the United States, Latin America, and the Anglophone Caribbean. ...

, and Astra
SES Astra
Astra is the name for the geostationary communication satellites, both individually and as a group, which are owned and operated by SES S.A., a global satellite operator based in Betzdorf, in eastern Luxembourg. The name is sometimes also used to describe the channels broadcasting from these...

. Rather than a few dozen channels with a few subchannels each, these services map to a range of hundreds of individually numbered channels. This is true of digital cable
Digital cable
Digital cable is a generic term for any type of cable television distribution using digital video compression or distribution. The technology was originally developed by Motorola.-Background:...

 and satellite radio
Satellite radio
Satellite radio is an analogue or digital radio signal that is relayed through one or more satellites and thus can be received in a much wider geographical area than terrestrial FM radio stations...

 services, as well.


In Japan, digital terrestrial TV broadcasters in each region are allocated a "remote control key ID" (or, "remocon key ID"), currently numbered from 1 to 12. Remote control ID allocations for broadcasters outside the Kanto region
Kanto region
The is a geographical area of Honshu, the largest island of Japan. The region includes the Greater Tokyo Area and encompasses seven prefectures: Gunma, Tochigi, Ibaraki, Saitama, Tokyo, Chiba, and Kanagawa. Within its boundaries, slightly more than 40 percent of the land area is the Kantō Plain....

 generally follow their Tokyo-based network flagships, however stations in some regions deviate from this. Current technical standards allow for expansion to a maximum of 16 broadcasters per region.

Each underlying channel is then assigned a three-digit number, which is based on their assigned remote control ID, followed by the sub-channel number. For example, NHK Educational TV
NHK Educational TV
is the second television service of NHK . It is a sister service of NHK General TV, showing programs of a more educational, cultural or intellectual nature, periodically also showing anime...

 is assigned remote control ID 2 (nationwide). Their primary channel is therefore assigned virtual channel 021. If the broadcaster multichannels (of which the ISDB-T standard allows up to three standard definition streams), the additional streams would be assigned virtual channels 022 and 023, respectively. Current standards allow for a maximum of eight virtual channels per broadcaster (in this example 021-028).

Additional datacasting services use virtual channels in the 200-799 range - in this example, the network could use the 22x, 42x and 62x ranges.


As the Philippines started its transition to digital terrestrial television back in 2008, virtual channels have been tentatively assigned to TV networks who are now in operation. In June 2010, the National Telecommunications Commission finally adopted ISDB
Integrated Services Digital Broadcasting is a Japanese standard for digital television and digital radio used by the country's radio and television stations. ISDB replaced the previously used MUSE "Hi-vision" analogue HDTV system...

-T as the sole digital terrestrial television standard in the country.

LCN used in ISDB-T in the Philippines was pre-assigned to the currently operating networks in digital TV. Small-player GEM HD on DZCE-TV
GEMNET is the first to test broadcast on DTV channel 49 is the flagship station of the Philippine Television Network GEMNET. It is currently the UHF television station of Christian Era Broadcasting Service, a broadcast ministry of the independent Philippine Christian church, the Iglesia ni Cristo,...

 was the first ever Philippine TV network to go ISDB
Integrated Services Digital Broadcasting is a Japanese standard for digital television and digital radio used by the country's radio and television stations. ISDB replaced the previously used MUSE "Hi-vision" analogue HDTV system...

-T, being assigned to LCN 2.11 which is using the analog channel 49. Government-owned National Broadcasting Network
National Broadcasting Network
People's Television is the flagship government television network owned by the Philippine Government through People's Television Network, Inc. . Its head office, studios and transmitter are located at Broadcast Complex, Visayas Avenue, Diliman, Quezon City .-History:The country's government...

 or NBN was assigned to 1.1 using its analog channel 48 because of its status as government-owned. High definition
High-definition television
High-definition television is video that has resolution substantially higher than that of traditional television systems . HDTV has one or two million pixels per frame, roughly five times that of SD...

 channels are being assigned with the decimal with "11", while a multiple-SD channel uses decimal with "1, 2, 3... and so on" as its subchannel.

In the first quarter of 2011, the NTC convened to form the TWG-IRR that will draft the implementing rules and regulations on digital TV. Aside from that, it will cover the frequency planning for the upcoming TV networks that will go digital.

Digital radio

Digital radio
Digital radio
Digital radio has several meanings:1. Today the most common meaning is digital radio broadcasting technologies, such as the digital audio broadcasting system, also known as Eureka 147. In these systems, the analog audio signal is digitized into zeros and ones, compressed using formats such as...

 also uses channels and subchannels in the DAB
Digital audio broadcasting
Digital Audio Broadcasting is a digital radio technology for broadcasting radio stations, used in several countries, particularly in Europe. As of 2006, approximately 1,000 stations worldwide broadcast in the DAB format....

 format. iBiquity's HD Radio
HD Radio
HD Radio, which originally stood for "Hybrid Digital", is the trademark for iBiquity's in-band on-channel digital radio technology used by AM and FM radio stations to transmit audio and data via a digital signal in conjunction with their analog signals...

 uses HD1, HD2, ..., HD7 channels. HD1-3 are available in FM hybrid mode, while all seven HD channels are available in the pure digital mode.

In-band on-channel
In-band on-channel is a hybrid method of transmitting digital radio and analog radio broadcast signals simultaneously on the same frequency....

 system (Digital Radio Mondiale
Digital Radio Mondiale
Digital Radio Mondiale is a set of digital audio broadcasting technologies designed to work over the bands currently used for AM broadcasting, particularly shortwave...

) stations do not currently use any virtual channels because of the limited bandwidth available in analog sidebands.

External links

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