SMT Antennas Developed For Multi-Band, Multi-Mode Mobile Phones

Measuring only a few millimeters square, a family of surface-mount ceramic antennas has been developed for use directly on the pc boards of mobile phones. By mounting the antenna inside the phone, the chances of mechanically damaging it during use of the phone is said to be completely eliminated. The family embraces two different series: Dielectric Resonator Antennas (DRAs) for narrow-band applications, such as Bluetooth, W-LAN, pagers and DECT; and Printed Wire Antennas (PWAs) for wide-band uses, such 900/1800-MHz dual-band GSM phones. Formed in the shape of small, monolithic ceramic block, DRAs can also be used as a second diversity antenna in many applications to improve voice quality or data reception. The initial, GSM900/1800-MHz version of the PWAs measures only 11 x 17 mm and has a mounting height of just 2 mm, making the device also suitable for use in PDAs. The antennas can be inserted on boards and soldered using standard SMT production equipment.