Digital radio

Comparison of frequency band designations

Use of digital technology to transmit or receive across the radio spectrum.

- Digital radio

425 related topics


Digital broadcasting

Practice of using digital signals rather than analogue signals for broadcasting over radio frequency bands.

A binary signal, also known as a logic signal, is a digital signal with two distinguishable levels

Digital audio broadcasting is being adopted more slowly for radio broadcasting where it is mainly used in Satellite radio.

HD Radio

An example of information displayed by an AM HD station locking.
HD Radio transmitter
Spectrum of FM broadcast station without HD Radio
Spectrum of FM broadcast station with HD Radio
Spectrum of a HD Radio station as shown by a RTL-SDR USB device. The usual bandwidth of a regular FM station is visible as the marker width in the top image.
HD‑1 signal on KOST 103.5 FM in a Volkswagen RCD‑510 receiver
Sangean HDR‑14 portable receiver playing San Diego's KPBS-FM HD‑2 channel, "Classical 24".

HD Radio (HDR) is a trademark for an in-band on-channel (IBOC) digital radio broadcast technology.

Audio coding format

Comparison of coding efficiency between popular audio formats
Solidyne 922: The world's first commercial audio bit compression sound card for PC, 1990

An audio coding format (or sometimes audio compression format) is a content representation format for storage or transmission of digital audio (such as in digital television, digital radio and in audio and video files).


DTT broadcasting systems. Countries using ISDB are shown in green.
Treeview of ISDB-T, channels, Segments and arranging multiple program broadcasting.

Integrated Services Digital Broadcasting (ISDB; Japanese: 統合デジタル放送サービス, Tōgō dejitaru hōsō sābisu) is a Japanese broadcasting standard for digital television (DTV) and digital radio.

High-Efficiency Advanced Audio Coding

Branded HD-AAC.

Hierarchical structure of AAC profile, HE-AAC profile and HE-AAC v2 profile, and compatibility between them. The HE-AAC profile decoder is fully capable of decoding any AAC profile stream. Similarly, The HE-AAC v2 decoder can handle all HE-AAC profile streams as well as all AAC profile streams. Based on the MPEG-4 Part 3 technical specification.
Evolution from MPEG-2 AAC-LC (Low Complexity) Profile and MPEG-4 AAC-LC Object Type to HE-AAC v2 Profile.

HE-AAC is used in digital radio standards like HD Radio, DAB+ and Digital Radio Mondiale.

Digital Radio Mondiale

Official DRM logo

Digital Radio Mondiale (DRM; mondiale being Italian and French for "worldwide") is a set of digital audio broadcasting technologies designed to work over the bands currently used for analogue radio broadcasting including AM broadcasting—particularly shortwave—and FM broadcasting.

Digital audio radio service

Comparison of frequency band designations

Digital audio radio service (DARS) refers to any type of digital radio program service.


Process of varying one or more properties of a periodic waveform, called the carrier signal, with a separate signal called the modulation signal that typically contains information to be transmitted.

Categorization for signal modulation based on data and carrier types
A low-frequency message signal (top) may be carried by an AM or FM radio wave.
Waterfall plot of a 146.52 MHz radio carrier, with amplitude modulation by a 1,000 Hz sinusoid. Two strong sidebands at + and - 1 kHz from the carrier frequency are shown.
A carrier, frequency modulated by a 1,000 Hz sinusoid. The modulation index has been adjusted to around 2.4, so the carrier frequency has small amplitude. Several strong sidebands are apparent; in principle an infinite number are produced in FM but the higher-order sidebands are of negligible magnitude.
Schematic of 4 baud, 8 bit/s data link containing arbitrarily chosen values

A more complicated digital modulation method that employs multiple carriers, orthogonal frequency-division multiplexing (OFDM), is used in WiFi networks, digital radio stations and digital cable television transmission.

In-band on-channel

A broadcasting antenna in Stuttgart

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

Radio broadcasting

Transmission of audio , sometimes with related metadata, by radio waves to radio receivers belonging to a public audience.

Long wave radio broadcasting station, Motala, Sweden
Slovak Radio Building, Bratislava, Slovakia (architects: Štefan Svetko, Štefan Ďurkovič and Barnabáš Kissling, 1967–1983)
Broadcasting tower in Trondheim, Norway
Advertisement placed in the November 5, 1919 Nieuwe Rotterdamsche Courant announcing PCGG's debut broadcast scheduled for the next evening.
Use of a sound broadcasting station
Transmission diagram of sound broadcasting (AM and FM)
AM broadcasting stations in 2006
FM radio broadcast stations in 2006
Worldwide presence of Radio Maria broadcasters.

Radio stations broadcast with several different types of modulation: AM radio stations transmit in AM (amplitude modulation), FM radio stations transmit in FM (frequency modulation), which are older analog audio standards, while newer digital radio stations transmit in several digital audio standards: DAB (digital audio broadcasting), HD radio, DRM (Digital Radio Mondiale).