Ultra-selective 22-pole 10-transmission zero superconducting bandpass filter surpasses 50-pole Chebyshev filter

Author

Tsuzuki, Genichi ; Ye, Shen ; Berkowitz, Stuart

Author_Institution

Conductus Inc., Sunnyvale, CA, USA

Volume

50

Issue

12

fYear

2002

fDate

12/1/2002 12:00:00 AM

Firstpage

2924

Lastpage

2929

Abstract

An ultra-selective filter for third-generation (3G) and fourth-generation wireless application is presented. The demonstrated filter consists of 22 resonators and five cross couplings that produce ten transmission zeros. The filter was designed at 1950-MHz center frequency with a 20-MHz bandwidth to meet existing 3G wireless applications. The measured filter data shows excellent selectivity, better than 30-dB/100-kHz skirt slopes, and 90 dB of rejection at 350 kHz from the band edge. This filter performance surpasses the performance of a 50-pole Chebyshev filter. In order to fit a large number of resonators into a limited wafer area, a new compact resonator was developed. The filter was fabricated using a YBCO thin film on a 2-in MgO wafer.

Keywords

Chebyshev filters; UHF filters; band-pass filters; barium compounds; high-temperature superconductors; poles and zeros; resonator filters; superconducting filters; superconducting resonators; yttrium compounds; 1950 MHz; 20 MHz; Chebyshev filter; MgO; MgO wafer; YBCO thin film; YBaCuO; cross coupling; fourth-generation wireless application; high temperature superconductor; resonator; third-generation wireless application; transmission zeros; ultra-selective multipole superconducting bandpass filter; Band pass filters; Bandwidth; Chebyshev approximation; Couplings; Filtering theory; Frequency; Resonator filters; Superconducting filaments and wires; Superconducting filters; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/TMTT.2002.805154

Filename

1098014