In this paper a dual-band bandpass filter using loaded stub in the ring resonator and etched nested C-shape defected ground structure (DGS) on ground plane is reported. The operating frequencies of the bandpass filter are selected for applications in Bluetooth (2.4 GHz-2.484 GHz) and WLAN (5.15 GHz-5.35 GHz) systems. Due to its applications in WLAN and Bluetooth system the filter will be subjected to high EM radiation from the antenna and nearby sources. Therefore, susceptibility study of such filter is very important. The susceptibility study of the filter has been carried out by subjecting the structure to an interference source. Experimental results are presented and analyzed.
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