Multi-band antenna design for full metal casing mobile handset

A multi-band antenna for full metal casing mobile handset is proposed. The wide-band feed structure is used for implementing wide-band performance. The size of the antenna is 6 mm × 48 mm and a narrow ground clearance of 6 mm × 70 mm can be achieved. The experimental results reveal that a good impendence matching across the bands of 824-960 MHz and 1710-2690 MHz. In addition, the total efficiency of the proposed antenna is better than 40%. The antenna is shown to have good performance with user's hand and it can satisfy the requirements of specific absorption rate (SAR). The most highlight of this antenna is that it provides a method to overcome the difficulties for full metal casing and narrow-frame smartphone.