Digital Audio Broadcasting (DAB)
A digital radio broadcasting standard, used to broadcast radio programs and podcasts on VHFVery High Frequency (30-300 MHz) and UHFUltra High Frequency (300-3000 MHz) bands using digital modulation technologies. It is succeeded by DAB+ (Digital Audio Broadcasting Plus), which is not backwards compatible. DAB offers better audio quality and robustness than most analog methods used in traditional radio broadcasts because of its resistance to multipath fading. The only disadvantage is its quality drops sharply when signal strength reaches below a certain threshold. For a signal-to-noise ratio of 13 dBThe decibel (dB) is a logarithmic unit used to express the ratio of two values of a physical quantity, here the strength of a received signal. (which is the minimum required for error-free demodulation), the sensitivity is -86 dBm. In comparison to a FMFrequency Modulation radio receiver having a sensitivity of -120 dBm (at 12 dBThe decibel (dB) is a logarithmic unit used to express the ratio of two values of a physical quantity, here the strength of a received signal. SINAD and 1 kHzKiloHertz (kHz) 10^3 Hz tone), DAB has less receiver sensitivity thus coverage. To compensate for this, DAB broadcast transmitters broadcast at a much higher power than FMFrequency Modulation counterparts. On the other hand, DAB is more energy and bandwidth efficient than AMAmplitude Modulation/FMFrequency Modulation. As of 2017, over 38 countries have adopted this standard.
Frequencies[edit]
In most countries specified by the Band III and L-band plans which are 174.928 MHzMegaHertz (MHz) 10^6 Hz - 239.200 MHzMegaHertz (MHz) 10^6 Hz, 1452.960 MHzMegaHertz (MHz) 10^6 Hz - 1490.625 MHzMegaHertz (MHz) 10^6 Hz respectively. DAB broadcasts a single multiplex that is 1.5 MHzMegaHertz (MHz) 10^6 Hz wide. Actual bandwidth is 1.536MHz.
See DAB Ensembles Worldwide for a list of DAB frequencies per country. Also DAB Ensembles Band Plans for a list of band plan frequencies.
Decoding Software[edit]