Wideband is a broad frequency communication channel that is dependent on relative coherence bandwidth, which measures the maximum time intervals between comparable fading amplitude signals. Communications media often have data transfer rates with wideband connection requirements.
Techopedia explains Wideband
Wideband audio, which is regularly deployed with voice over Internet Protocol communications, has the following features:
Higher quality sound transmission
Background noise reduction
A doubling of traditional telephonic sampling, which occurs at 8,000 times per second
Increased sound spectrum width
Decreased bandwidth requirements to 32 Kbps, which is half the required maximum for public switched telephone networks