A five-band, seven-mode antenna and RF front-end system for clamshell phones

A five-band, seven-mode antenna and AIM system is presented for use within a clamshell phone. The antennas are much smaller than conventional tri- and quad band designs due to co-design of the antennas and the AIM: the total volume occupied by the antennas is just 1.08 cm³. They are also self-diplexing, allowing band specific matching and simultaneous operation in GSM and UTRA modes without the addition of a lossy diplexer. It is shown that the concept works well when the phone is open and closed - i.e., a satisfactory compromise can be found between these modes.