More than 20% bandwith is considered UWB, but nearly all practical UBW antennas have 100% bandwith or more.Biconicals and Vivaldi are most common UWB antennas.
There are a wide range of definitions of what is wide band. Just be cautious and make sure you are using a definition that is consistent with the definition your customer uses.
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There are a wide range of definitions of what is wide band. Just be cautious and make sure you are using a definition that is consistent with the definition your customer uses.