Design & Simulation of a Compact Multi Band Microstrip Bandpass Filter using C shaped Stub Loaded Resonators

A compact Stub Loaded Tri-band bandpass filter is presented through this paper. The proposed filter will be able to operate simultaneously at GSM, 3G and WiMAX frequency pass bands. This Bandpass filter is designed utilizing the concept of stub-Loaded resonators (SLR). By appropriately choosing the proper length and width of middle stub, we can shift the resonant frequencies of even mode without affecting any changes to that of the frequencies of the odd mode. This eases the structure and calibration of the Tri-band bandpass filter. Three passbands surrounded by six transmission zeros (TZs) make the pass band groups properly isolated.