In recent years, the mobile phone manufacturers have §increasingly focused on thinner and more §mechanically mixed products. These devices need to §be able to be operating with several different §mobile phone systems and in different frequency §bands. Based on the evolution in the wireless §industry, the handsets need also to be equipped with §other wireless functionality such as WLAN, §Bluetooth, and GPS. In order to work in multi-band §wireless systems, the design of the mobile phone antenna becomes a key issue.Based on the work by §Vilanen et al., a small, low profile and efficient §coupling element based antenna with penta-band §operations for the use in mobile telephones has been §studied in this book. The antenna was designed by a §High Frequency Structure Simulator, HFSS, built and §verified. Cases with different antenna dimensions §also have been investigated for the coupling §affection. The resulting antennas operate over two §wide bands from (824-1300) MHz and from (1710-2170) §MHz, covering five cellular bands§(GSM850/900/1800/PCS1900 and UMTS).