Design method of miniaturized HTS coplanar waveguide bandpass filters using cross coupling

Abstract

A new design method of miniaturizing HTS coplanar waveguide bandpass filters using cross coupling is presented. When the size of the filter decreases, the cross coupling between the resonators tends to appear, which causes attenuation poles. In order to control the cross-coupling section, we redesigned the meanderline interval and shape, so that we can design the frequency and number of the attenuation poles. The half-wave length resonator bandpss filter (BPF) is designed by using the 2.5-dimensional electromagnetic field simulator. 7-pole cross-coupled CPW BPF (center frequency of 2 GHz, bandwidth of 15 MHz, ripple of 0.1 dB and two attenuation poles on both sides of pass band) is packed within 6 mm 10 mm substrate. Simulated performance is in good agreement with the designed one. This BPF has the skirt steepness of 20 dB/MHz (40 dB attenuation), which is the same skirt characteristic of 11-pole Chebyshev BPF. Moreover, we tested YBCO BPF by using our present design theory at cryogenic temperature.

Miniaturized UHF tunable filter using PCB embedding passive technology

“…It has relatively large size and difficulty of tuning since air core inductors are assembled on a board and controlled manually. To address these obstacles, tremendous efforts have been performed by utilizing new types of resonators, coupling structures [2,3], coupling methods [4], geometry configurations [5], and multi-level folded-line structures [6]. However, these filters are still too large to apply for compact TV tuner modules and systems.…”

“…The correlator improves size, insertion loss, and bandwidth better than correlator of conventional structure. The designed correlator can be used for the electronic warfare (EW) [1], ELINT systems in military area and a microwave measurements [2], vector analyzer, and mobile communication area. Microwave correlator used to intercept the RF signals must be able to meet these challenges.…”

Design and performance of 800MHz/2GHz dual band small planar antenna

“…This type antenna needs impedance matching circuit between antenna and signal source. We already have realized the matching circuit by transmission line and interdigital gap [3][4][5][6][7][8][9][10][11]. The proposed matching circuits have similar performances to band pass filter (BPF).…”

Design of a Miniaturized Superconducting Bandpass Filter by Evaluating the Kinetic Inductance in the K-Inverter

“…In our previous studies [5]- [7], we designed the miniaturized cross-coupled CPW BPF by using highly packed meanderline half-wavelength (λ/2) resonators and interdigital gaps (J-inverters). In this paper, for further miniaturization, we designed and tested quarter wavelength (λ/4) resonator BPF by using interdigital gaps and meander-shape inductors (K-inviters).…”