Design and Fabrication of Compact Microstrip Low-pass Filter with Thin Film Technique for Wideband Applications

Abstract

This paper introduces a compact microstrip low-pass filter (LPF) with a very sharp rejection. The proposed LPF is designed to be used for electronic warfare in defense industry. It has 62 dB/GHz attenuation rate, 10 GHz of stopband width and 48.6 dB of stopband attenuation. Moreover, it also has a wide passband and has a high cut-off frequency (f_c) of 6 GHz. The designed filter has been fabricated using alumina (Al2O3) substrate and titanium-gold (Ti-Au) coating on top of that with thin film technique in a clean room. The experimental measurements of the proposed LPF show great agreement with the simulation results, which validates that the presented filter is convenient to be used for applications up to C-band in electronic warfare systems.  

Keywords

• Low-pass filter
• Microstrip filter
• Thin film technique
• C-band

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