DAB ensembles are groups of Digital audio broadcasting

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....

 broadcast

Broadcasting

Broadcasting is the distribution of audio and video content to a dispersed audience via any audio visual medium. Receiving parties may include the general public or a relatively large subset of thereof...

ers transmit

Transmission (telecommunications)

Transmission, in telecommunications, is the process of sending, propagating and receiving an analogue or digital information signal over a physical point-to-point or point-to-multipoint transmission medium, either wired, optical fiber or wireless...

ting multiple 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...

 channels

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...

 on a single radio transmission

Transmission (telecommunications)

Transmission, in telecommunications, is the process of sending, propagating and receiving an analogue or digital information signal over a physical point-to-point or point-to-multipoint transmission medium, either wired, optical fiber or wireless...

.

The digital audio

Digital audio

Digital audio is sound reproduction using pulse-code modulation and digital signals. Digital audio systems include analog-to-digital conversion , digital-to-analog conversion , digital storage, processing and transmission components...

 feeds from each radio station

Radio station

Radio broadcasting is a one-way wireless transmission over radio waves intended to reach a wide audience. Stations can be linked in radio networks to broadcast a common radio format, either in broadcast syndication or simulcast or both...

 are multiplexed

Multiplexing

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...

 into one digital

Digital

A digital system is a data technology that uses discrete values. By contrast, non-digital systems use a continuous range of values to represent information...

 transmission, to be decoded by the receiver

Receiver (radio)

A radio receiver converts signals from a radio antenna to a usable form. It uses electronic filters to separate a wanted radio frequency signal from all other signals, the electronic amplifier increases the level suitable for further processing, and finally recovers the desired information through...

. While each station can use a different bitrate

Bitrate

In telecommunications and computing, bit rate is the number of bits that are conveyed or processed per unit of time....

, and either monophonic

Monaural

Monaural or monophonic sound reproduction is single-channel. Typically there is only one microphone, one loudspeaker, or channels are fed from a common signal path...

 or stereophonic (one or two channels of audio

Sound

Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.-Propagation of...

), all stations will have exactly the same coverage area. Each ensemble can only have a certain maximum total bitrate

Bitrate

In telecommunications and computing, bit rate is the number of bits that are conveyed or processed per unit of time....

, a sort of "bit budget

Budget

A budget is a financial plan and a list of all planned expenses and revenues. It is a plan for saving, borrowing and spending. A budget is an important concept in microeconomics, which uses a budget line to illustrate the trade-offs between two or more goods...

" that participating broadcasters must work within. Increasing the number of stations on an ensemble requires lower quality audio, and while increasing audio quality requires removing audio channels.

The 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...

 equivalent is called a multiplex, though in some parts of the world, TV stations use a full channel for their own programming (one HDTV

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...

 or multiplexed SDTV) and do not share with other stations. For example in the U.S., a private television station is assigned 6 megahertz exclusively, to be divided at its own discretion (WBAL

WBAL-TV

WBAL-TV is the NBC-affiliated television station in Baltimore, Maryland. It broadcasts a high definition digital signal on VHF channel 11. It is one of the flagship stations of Hearst Television, a wholly owned subsidiary of the Hearst Corporation, which also owns sister radio stations WBAL and...

11-1, 11-2, 11-3, et cetera).