In recent y 。 ars , th 已 UWB technolegy 正 n which high speed and short distance communication a 匸epossible is studi 巳d briskly , As a dcmand to a UWB antenna , it has a wide band characteristic , and is a small size , and the 爬 is almost no frequency dependency in a radiation pattern . In this paper , the small box type antenna for UWB with simplc structurc is propGscd . The antonna has 且O mm antenna h 巳 ight , and frequency bandwidth is flo皿 3 . lto l l . 5 GHz . Furthermore , it has an omnidirectional radiation