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

Year 2022, Volume: 35 Issue: 2, 558 - 565, 01.06.2022

Reşat Tüzün Nursel Akçam Tayfun Okan

https://doi.org/10.35378/gujs.826774

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

References

• [1] Jadeja, R., Faldu, A., Trivedi, T., Chauhan, S., Patel, V., “Compensation of harmonics in neutral current using active power filter for three phase four wire system”, Gazi Journal of Science, 31(3): 846-861, (2018).
• [2] Alboon, S. A., Karar, A. S., Mahariq, I., Al-Sheikh, B., “Reconfigurable thin film filter for compensating AOI deviation effects using LC coupled cavities”, Optics Communications, 456, 124672, (2020).
• [3] Ekhteraei, M., Hayati, M., Hossein Kazemi, A., Zarghami, S., “Design and analysis of a modified rectangular-shaped lowpass filter based on LC equivalent circuit”, AEU - International Journal of Electronics and Communications, 126, 153290, (2020).
• [4] Vala, A., Patel, A., Goswami, R., Mahant, K., “Defected ground structure based wideband microstrip low-pass filter for wireless communication”, Microwave and Optical Technology Letters, 59: 993-996, (2017).
• [5] Makki, S. V., Ahmadi, A., Majidifar, S., Sariri, H., Rahmani, Z., “Sharp Response Microstrip LPF using Folded Stepped Impedance Open Stubs”, Radioengineering, 22: 328-332, (2013).
• [6] Yang, R. Y., Lin, Y. L., Hung, C. Y., Lin, C. C., “Design of a compact and sharp rejection low-pass filter with a wide stopband”, Journal of Electromagnetic Waves and Applications, 26: 2284-2290, (2012).
• [7] Wang, L., Yang, H. C., Li, Y., “Design of compact microstrip low-pass filter with ultra-wide stopband using SIRs”, Progress in Electromagnetics Research Letters, 18: 179-186, (2010).
• [8] Hayati, M., Sheikhi, A., “Microstrip lowpass filter with very sharp transition band using T-shaped, patch, and stepped impedance resonators”, ETRI J., 35: 538–541, (2012).
• [9] Khezeli, M. R., Hayati, M., Lotfi, A., “Compact wide stopband lowpass filter using spiral loaded tapered compact microstrip resonator cell”, Int. J. Electron., 101: 375-382, (2014).
• [10] Zhang, C. F., “Compact and wide stopband lowpass filter with novel comb CMRC”, Int. J. Electron., 96: 749-754, (2009).
• [11] Moitra, S., Dey, R., Bhowmik, P. S., “Design and band coalition of dual band microstrip filter using DGS, coupled line structures and series inductive metallic vias”, Analog Integrated Circuits and Signal Processing, 101: 77-88, (2019).
• [12] Kant, R., Gupta, N., “Design and implementation of inverse legendre microstrip filter”, Microwave and Optical Technology Letters, 59: 69-73, (2016).
• [13] Nath, J., Ghosh, D., Maria, J. P., Kingon, A. I., Fathelbab, W., Franzon, P. D., Steer, M. B., “An electronically tunable microstrip bandpass filter using thin-film Barium-Strontium-Titanate (BST) varactors”, IEEE Trans. on Microw Theory Tech., 53: 2707-2712, (2005).
• [14] Jeong, S.-M., Kang, Y., Lim, T., Ju, S., “Chemically Reactive Polyurethane-Carbon Nanotube Fiber with Aerogel-Microsphere-Thin-Film Selective Filter”, Advanced Materials Interfaces, 5: 1-6, (2018).
• [15] Zhang, W., Gu, J., Xu, G., Luo, L., Li, X., “Copper/benzocyclotene thin film technique based microstrip bandpass filter featured by thick dielectric layer for low insertion loss”, Microwave and Optical Technology Letters, 62: 3695-3701, (2020).
• [16] Nasraoui, H., Capobianco, A. D., Mouhsen, A., El-Aoufi, J., Mouzouna, Y., Taouzari, M., “Compact wideband band pass microstrip filter loaded by triangular split ring resonators”, Microwave and Optical Technology Letters, 59: 3101–3107, (2017).
• [17] Quijano, G. P., Carchon, G. J., Nauwelaers, B. K. J. C., Raedt, W., “Horizontal Integration of Cavity Filters on High-Resistivity Silicon Thin-Film Technology”, IEEE Trans. on Microw. Theory Tech., 56: 2893-2901, (2008).
• [18] Yu, J. J., Chew, S. T., Leong, M. S., Ooi, B. L., “New class of microstrip miniaturised filter using triangular stub”, Electronics Letters, 37(19): 1169-1170, (2001).
• [19] Wang, Y., Hong, W., Dong, Y., Liu, B., Tang, H. J., Chen, J., Yin, X., Wu, K., “Half Mode Substrate Integrated Waveguide (HMSIW) Bandpass Filter”, IEEE Microwave and Wireless Components Letters, 17(4): 265–267, (2007).
• [20] Boutejdar, A., Omar, A., Burte, E., Batmanov, A., Mikuta, R., “A new logarithmic method to minimize the size of low-pass filter using multilayer and defected ground structure technique”, Microwave and Optical Technology Letters, 53(11): 2561–2566, (2011).
• [21] Sagawa, M., Takahashi, K., Makimoto, M., “Miniaturized hairpin resonator filters and their application to receiver front-end MIC's”, IEEE Trans. Microwave Theory Tech., 37: 1991-1997, (1989).