Wideband mobile terminal antenna design using extended ground

In this paper, novel feeding method using extended ground is introduced. Branch structures operating as multi-resonator have been used to obtain wide bandwidth in the field of small antennas. However, poor anti-resonance may happen between resonances generated by branch structures due to wakened current intensity flowing branch structures. Thus, the proposed feeding method with extended ground under a feeding line improves the poor anti-resonance so that wide bandwidth can be achieved. An extended ground antenna designed in this paper achieves 27% relative impedance bandwidth at 1.9 GHz.