wideband

adj. broadband, having a wide frequency range; of or pertaining to wide requency range

In communications, wideband is a relative term used to describe a wide range of frequencies in a spectrum. A system is typically described as wideband if the message bandwidth significantly exceeds the channel's coherence bandwidth.A wideband antenna is one with the approximately or exactly the same operating characteristics over a very wide passband. Distinguished from broadband antennas, where the passband is large, but the gain and or pattern need not stay the same over the passband.Wideband in speech services means that the used speech frequency response covers 50-7000 Hz. The opposite of wideband is narrowband.
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Adjective
1. responding to or operating at a wide band of frequencies; "a broadband antenna"
(synonym) broadband
(pertainym) frequency band, waveband

1. The property of any communications facility, equipment, channel, or system in which the range of frequencies used for transmission is greater than 0.1 % of the midband frequency. (188 ) Note: "Wideband" has many meanings depending upon application. "Wideband" is often used to distinguish it from "narrowband," where both terms are subjectively defined relative to the implied context. 2. In communications security systems, a bandwidth exceeding that of a nominal 4-kHz telephone channel. (188 ) [From Weik '89] 3. The property of a circuit that has a bandwidth wider than normal for the type of circuit, frequency of operation, or type of modulation. 4. In telephony, the property of a circuit that has a bandwidth greater than 4 kHz. (188 ) 5. Pertaining to a signal that occupies a broad frequency spectrum. Synonym broadband. [From Weik '89]