Title :
MSK SAW tapped delay lines on LiTaO3 with moderate processing gain for CDMA indoor and mobile radio applications
Author :
Weigel, R. ; Knorr, C ; Wagner, K.C. ; Reindl, L. ; Seifert, F.
Author_Institution :
Inst. fur Hochfrequenztech., Tech. Univ. Munchen, Germany
Abstract :
We report on the design and performance of two SAM MSK Tapped Delay Lines (TDLs) using PN code sequences of length 128 chips, As a substrate, LiTaO3 has been used due to the system requirements of a given CDMA/TDMA system. Center frequency, bandwidth of the major lobe, and integration time were 266.66 MHz, 65.7 MHz, and 3 μs, respectively. TDL 1 employed two non-weighted transducers, whereas TDL 2 incorporated one cosine-apodized transducer. Split-fingers with a metalization height of 150 nm (aluminum) were used. The experimental data of both design approaches were very similar with an unmatched insertion loss of 37 dB which is improved by more than 18 dB by proper matching. Amplitude ripple was less than 1 and 2 db, respectively, and the close-in selectivity was 23 dB
Keywords :
code division multiple access; indoor radio; lithium compounds; minimum shift keying; mobile radio; pseudonoise codes; spread spectrum communication; surface acoustic wave delay lines; surface acoustic wave transducers; 266.66 MHz; 3 mus; 37 dB; 65.7 MHz; CDMA indoor radio; LiTaO3; MSK SAW tapped delay lines; PN code sequences; center frequency; close-in selectivity; cosine-apodized transducer; integration time; metalization height; mobile radio; nonweighted transducers; processing gain; split-fingers; unmatched insertion loss; Binary phase shift keying; Delay lines; Land mobile radio; Matched filters; Multiaccess communication; Pulse modulation; Radio frequency; Spread spectrum communication; Surface acoustic waves; Transducers;
Conference_Titel :
Ultrasonics Symposium, 1995. Proceedings., 1995 IEEE
Conference_Location :
Seattle, WA
Print_ISBN :
0-7803-2940-6
DOI :
10.1109/ULTSYM.1995.495562
