>> www.drm.org: Digital and analogue audio samples from DRM long-range evaluation tests.
The modulation in DRM is a coded Orthogonal Frequency Multiplexing (OFDM), which is also used for DVB and DAB.
It spreads a digital bit stream over a large number of lower bitrate carriers. Errors in the transmission path are suppressed by interleaving the bit stream in frequency and time and adding error correction. The final data stream is transmitted several bits at a time with radio symbols that are combinations of phase angle and amplitude.
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