Far East Journal of Electronics and Communications © 2017 Pushpa Publishing House, Allahabad, India http://www.pphmj.com http://dx.doi.org/10.17654/EC017040775 Volume 17, Number 4, 2017, Pages 775-780 ISSN: 0973-7006 Received: March 13, 2017; Accepted: April 29, 2017 Keywords and phrases: bandstop filter, ultra-miniaturized BPF, Ku-band BPF. A preliminary version of this paper was presented at the ICIDB-2016, Seoul, South Korea. ∗ Corresponding author Communicated by Gyanendra Prasad Joshi ULTRA-MINIATURIZED MICROSTRIP RESONATOR BANDPASS FILTER FOR Ku-BAND APPLICATIONS Bhanu Shrestha and Changho Seo ∗ Department of Electronic Engineering Kwangwoon University 20 Kwangwoon Nowon-Gu 01897 Seoul, Korea Department of Applied Mathematics Kongju National University Kongju 32588 Korea Abstract In this paper, we present an ultra-miniaturized microstrip bandpass filter (BPF) operating at 14 GHz. One miniaturized hairpin resonator is used which is coupled in both input and output ports giving the BPF response. The gap of the hairpin configuration is represented by a capacitance. This proposed bandpass resonator filter is designed in ultra-miniaturized with good S-parameter responses. The overall dimension of the designed BPF is 1.245 mm by 0.812 mm. It is fabricated on Teflon substrates with relative permittivity, 54 . 2 = ε re with thickness of 0.54 mm.