Title :
A very small MMIC variable filter based on a new active filter design concept
Author :
Suwaki, Hideo ; Ohira, Takashi
Author_Institution :
NTT Radio Commun. Syst. Lab., Yokosuka, Japan
Abstract :
A novel MMIC (monolithic microwave IC) active filter is proposed for realizing a small-size variable bandpass filter with high selectivity at microwave frequencies. A second-order bandpass filter based on the proposed design concept occupies a 1.2*1.3 mm/sup 3/ area on the GaAs substrate. It is controllable for both quality factor Q, varying from 20 to 200, and a center frequency wider than 100 MHz at the 1.3 GHz band. A fourth-order bandpass filter was also fabricated by cascading two of the filter chips together. This is expected to be a key device in the future development of frequency-variable equipment. The design concept, fabrication, and measured performance of the filter are described.<>
Keywords :
III-V semiconductors; MMIC; Q-factor; active filters; band-pass filters; frequency control; gallium arsenide; microwave filters; tuning; 1.2 to 1.3 mm; 1.3 GHz; 100 MHz; GaAs substrate; Q-factor control; active filter design concept; centre frequency control; design concept; fabrication; filter chips; fourth-order bandpass filter; frequency-variable equipment; high selectivity; measured performance; microwave active filters; microwave frequencies; monolithic microwave IC; second-order bandpass filter; small MMIC variable filter; variable bandpass filter; Active filters; Band pass filters; Fabrication; Gallium arsenide; MMICs; Microwave filters; Microwave frequencies; Microwave integrated circuits; Monolithic integrated circuits; Q factor;
Conference_Titel :
Gallium Arsenide Integrated Circuit (GaAs IC) Symposium, 1990. Technical Digest 1990., 12th Annual
Conference_Location :
New Orleans, LA, USA
DOI :
10.1109/GAAS.1990.175458
