Title :
A 900 MHz 90 degrees hybrid for QPSK modulator
Author :
Arai, S. ; Kato, A. ; Minami, K. ; Nishikawa, T.
Author_Institution :
Murata Manuf. Co. Ltd., Kyoto, Japan
Abstract :
A miniaturized surface-mounting 90-degrees hybrid using a meandered thin-film microstrip line directional coupler has been developed for a QPSK (quadrature phase shift keying) modulator. The coupling level of the narrowly space parallel lines on a high dielectric constant (K) ceramic substrate was calculated using the finite element method (FEM) and a circuit simulator. Balanced outputs and quadrature phase difference in the frequency range of 950 MHz+or-10 MHz were obtained experimentally with a size of 1.7 (H)*4.8 (W)*6.2 (D) mm.<>
Keywords :
cellular radio; directional couplers; modulators; phase shift keying; strip line components; 940 to 960 MHz; QPSK modulator; balanced outputs; circuit simulator; coupling level; digital cellular radio; finite element method; high dielectric constant ceramic substrate; meandered thin-film microstrip line directional coupler; quadrature phase difference; surface-mounting hybrid; Ceramics; Coupling circuits; Dielectric substrates; Dielectric thin films; Directional couplers; High-K gate dielectrics; Microstrip; Phase modulation; Quadrature phase shift keying; Thin film circuits;
Conference_Titel :
Microwave Symposium Digest, 1991., IEEE MTT-S International
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-87942-591-1
DOI :
10.1109/MWSYM.1991.147142
