In order to avoid the interference of narrowband signals to ultra wideband（ UWB） systems

a butterfly six band-notched UWB antenna is designed.Expanded bandwidth with improved floor structure

U-shaped slits and I-shaped slits are respectively etched on the butterfly radiation patch

the microstrip feed

and the floor

and adding symmetric L-shaped narrow-band branches and split resonant ring（ SRR） on both sides of the microstrip feed and the floor to realize the antenna six notch characteristics.The principle of antenna notch generation is analyzed

and the influence of antenna size parameters on notch is studied.Through simulation analysis

the antenna can effectively suppress the interference of narrow-band systems in the frequency range of 2.8 ～ 11.4 GHz.The antenna size is 32 mm × 24 mm × 1.6 mm

and the structure is relatively compact.It can be widely used in various UWB communication systems.