INTERNAL MONOPOLE ANTENNA INTEGRATED WITH A SHIELDING METAL CASE FOR UMTS MOBILE DEVICES

摘要

An integration design of an internal monopole antenna and an RF shielding metal case for application in UMTS mobile devices is proposed. The monopole antenna is a low-profile (only 3.5-mm) T-shape strip monopole placed above and integrated (through short-circuiting) to the shielding metal case, which is flush with the top edge of the system ground plane of the mobile device. With the integrated shielding case, which provides a coupling-free region for the nearby components such as the RF module, RF circuitry, and battery in the mobile device, possible coupling between the monopole antenna and the nearby components can be avoided. The proposed integration design can thus lead to no degrading effects on the performances of the internal monopole antenna employed in the mobile device.