Title :
Balanced front-end hybrid SAW modules with impedance conversion
Author :
Doberstein, Sergei A. ; Razgoniaev, Vladimir K.
Author_Institution :
ONIIP, Omsk, Russia
Abstract :
This paper presents the new balanced front-end hybrid SAW modules with impedance conversion in a fractional bandwidth of 1.5-7% for 146-174 MHz handheld transceivers. The modules are connected between a low impedance antenna and high impedance double balanced mixer (DBM). 2 balanced SAW filters connected across a low noise amplifier are used in these modules. The balanced low-loss ring SAW filters on 128 °YX LiNbO3 and three-transducer SAW filters with unidirectional IDTs having U-shaped MSCs on 128°YX, 64°YX, 41°YX LiNbO3 are used. An optimization of a SAW filter-amplifier-SAW filter system was provided with a computer simulation using the equivalent circuit model. The 155-169 MHz balanced front-end SAW modules have shown a 3-dB bandwidth of 2.3-11 MHz, 12 dB gain, suppression above 80 dB. The modules are housed in the 16×7.3×2.6 mm SMD packages.
Keywords :
equivalent circuits; frequency response; mobile handsets; surface acoustic wave filters; surface mount technology; 12 dB; 128 °YX LiNbO3; 155 to 169 MHz; 16 mm; 2.3 to 11 MHz; 2.6 mm; 7.3 mm; LiNbO3; U-shaped MSCs; balanced front-end hybrid SAW modules; balanced low-loss ring SAW filters; equivalent circuit model; fractional bandwidth; handheld transceivers; high impedance double balanced mixer; impedance conversion; low impedance antenna; low noise amplifier; suppression; three-transducer SAW filters; unidirectional IDTs; 1f noise; Bandwidth; Computer simulation; Equivalent circuits; Gain; Impedance; Low-noise amplifiers; SAW filters; Surface acoustic waves; Transceivers;
Conference_Titel :
Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE
Print_ISBN :
0-7803-7582-3
DOI :
10.1109/ULTSYM.2002.1193367
