Ultra-wideband PIFA with a capacitive feed for penta-band operation in the folder-type mobile phone

A novel planar inverted-F antenna with a capacitive feed to generate a very wide operating band for penta-band operation in the folder-type mobile phone has been proposed. The antenna is simple in geometry and occupies a compact volume to allow it to be easily embedded inside the housing of the mobile phone to operate as an internal antenna. For both the open (in-use) and close (standby) states of the folder-type mobile phone, the obtained bandwidth of the antenna can cover GSM850/900/1800/1900/UMTS operation. Good radiation efficiency over the operating band has also been obtained.