Study and Enhanced Design of RF Dual Band Bandpass Filter Validation and Confirmation of Experimental Measurements

Mohamed Mabrouk, Leila Bousbia

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DOI: 10.4236/cs.2011.24041                

Abstract

Dual band bandpass filter is designed and optimized for RF wireless applications. The performances of that RF dual band filter are improved especially parameters describing the insertion loss, return losses and rejection. Dual-band bandpass filter using stub loaded resonators is designed and characterized. Theoretical results are compared with experimental data. This comparison shows that the magnitude of reflection coefficient S₁₁ from ADS^TM simulation is better than 28.0 dB, and the insertion loss S₂₁ is less than 0.5 dB. The two rejections are also better than 32.0 dB. The simulated results also show that two central frequencies are located at desired 1.82 and 2.95 GHz. Comparison of measured and simulated results shows frequency drift. The main reason for this frequency shifting is due to some uncertainties. These are obviously due to geometrical and physical parameters H and εr respectively of Duroid substrate used during design and measurements.

Keywords

RF Filters, Dual Bandpass, Effective Permittivity, Physical And Geometrical Parameters

Conflicts of Interest

The authors declare no conflicts of interest.

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