An antenna design technique which allows antennas to be self-matched while supporting multi-band and broadband operations. The technique includes adding a raised and curved ground plane section electrically coupled to the ground plane. The curved ground plane section allows for a smooth transition of the surface current hence a boarder bandwidth is achieved. A slit positioned between the ground plane and the ground plane section can also be used to further improve the antenna bandwidth. The technique does not increase the antenna thickness neither its volume, thus allowing application in slim handheld device applications such as flip phones. Using this technique, a narrow band antenna is made broadband to cover several frequency bands of interest. The technique is applied to a quad-band antenna to broaden its bandwidth to become a sept-band antenna. The technique is used to also improve the antenna match at all the seven bands it supports.