Wave transmission lines and networks – Coupling networks – Electromechanical filter
Patent
1997-07-23
1999-04-06
Pascal, Robert
Wave transmission lines and networks
Coupling networks
Electromechanical filter
333194, 310313B, H03H 964
Patent
active
058924183
ABSTRACT:
The present invention provides surface acoustic wave devices which do not require a balanced-to-unbalanced transformer circuit regardless of the type of the peripheral circuits of the balanced type surface acoustic wave filter, i.e. a balanced type device or an unbalanced type. A transmitting interdigital transducer and a receiving interdigital transducer are formed on a substrate comprising 41.degree. Y cut-X propagation lithium niobate. A balanced type surface acoustic wave filter is formed on a substrate comprising 36.degree. Y cut-X propagation lithium tantalate. The balanced type surface acoustic wave filter comprises two series-arm surface acoustic wave resonators and two crossed-arm surface acoustic wave resonators connected in a lattice. The substrate on which the transmitting interdigital transducer and the receiving interdigital transducer are formed and the substrate on which the balanced type surface acoustic wave filter is formed are located in a ceramic package. One of the input terminals of the transmitting interdigital transducer is grounded. The output terminals of the receiving interdigital transducer are connected to the input terminals of the balanced type surface acoustic wave filter.
REFERENCES:
patent: 3573673 (1971-04-01), De Vries et al.
patent: 3886504 (1975-05-01), Hartmann et al.
patent: 4044321 (1977-08-01), Vasile
patent: 4126837 (1978-11-01), Koyamada et al.
patent: 4278492 (1981-07-01), Cross et al.
patent: 4354130 (1982-10-01), Ono et al.
patent: 4785270 (1988-11-01), Krisman
patent: 5093638 (1992-03-01), Krisman et al.
patent: 5265267 (1993-11-01), Martin et al.
patent: 5365138 (1994-11-01), Saw et al.
patent: 5508667 (1996-04-01), Kondratiev et al.
patent: 5561406 (1996-10-01), Ikata et al.
patent: 5568002 (1996-10-01), Kawakatsu et al.
patent: 5692279 (1997-12-01), Mang et al.
patent: 5790000 (1998-08-01), Dai et al.
Sharif et al, M.A.; "Coupled Resonator Filters with Differential Input and/or Differential Output"; IEEE Ultrasonics Symposium Proceedings, vol. 1, pp. 67-70; Nov. 7-10, 1995, Conference Seattle, Wash. USA, Nov. 1995.
O. Ikata et al., "Development of Low-Loss Band-Pass Filters Using Saw Resonators for Portable Telephones", Ultrasonics Symposium, pp. 111-115.
Mitsutaka Hikita et al., "Miniaturized SAW Devices for Radio Communication Transceivers", IEEE Transactions on Vehicular Technology, vol. 38, No. 1, pp. 2-8.
James Heighway et al., "Balanced Bridge Inpedance Element Saw Filters", Proceedings on 1994 MTT-Symposium (WE4A-2).
Eda Kazuo
Onishi Keiji
Seki Shun-ichi
Taguchi Yutaka
Matsushita Electric - Industrial Co., Ltd.
Pascal Robert
Summons Barbara
LandOfFree
Balanced type surface acoustic wave device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Balanced type surface acoustic wave device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Balanced type surface acoustic wave device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1374875