Hardware-One has posted an article on Digital Audio Broadcasting. Here a blurb:

DAB uses a modulation technique called COFDM in order to overcome the problems associated with traditional FM/AM transmissions namely
interference. It is broadcast on terrestrial networks.

COFDM stands for Coded Orthogonal Frequency Division Multiplex. This system uses a mathematical relationship to split the radio signal across 1,536 different carrier frequencies as well as across a time lag. This ensures that, even if some of the signals are affected by interference or the signal is lost for a short period, the receiver is still capable of recovering the original source and reconstructing it perfectly.

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