Bandwidth enhancement for multi-band slot antenna by PBG feed

The paper presents a novel feeding technique to enhance the impedance bandwidth of multi-band slot antenna. The proposed feeding structure is based on the photonic band gap concept. By replacing the conventional CPW feedline of the multi-band slot antenna with a PBG feedline, the impedance bandwidth can be effectively enhanced for all resonance frequencies. A PBG-fed multi-band slot antenna and a reference antenna have been fabricated and measured. Comparison shows the validity of our approach, as the bandwidths increase from 7% to 10% at 1.88 GHz; from 8% to 16% at 2.45 GHz and from 8.3% to 20.8% at 3.5 GHz, respectively.