Wave transmission lines and networks – Coupling networks – Electromechanical filter
Reexamination Certificate
2005-08-10
2008-09-16
Summons, Barbara (Department: 2817)
Wave transmission lines and networks
Coupling networks
Electromechanical filter
C333S195000
Reexamination Certificate
active
07425882
ABSTRACT:
In a balanced-type surface acoustic wave filter, IDTs in the center of each of first and second longitudinally coupled resonator type surface acoustic wave filter sections are connected to an unbalanced input terminal, first and third IDT sections on both the sides of the center IDT are connected to first and second balanced output terminals, respectively, the first and third IDTs have narrow pitch electrode finger sections N, and when an electrode finger pitch of the narrow pitch electrode finger section of the second IDT is P1, an electrode finger pitch of the narrow pitch electrode finger section of the first and third IDTs is P2, the number of electrode fingers of the second IDT except for the narrow pitch electrode finger section of the IDT is K1, and the number of electrode fingers of the first and third IDT except for the narrow pitch electrode finger section is K2, P1>P2and 1.12≦K1/K2≦1.65 are satisfied.
REFERENCES:
patent: 2002/0000898 (2002-01-01), Takamine
patent: 2002/0021195 (2002-02-01), Takamine
patent: 2002/0175783 (2002-11-01), Watanabe et al.
patent: 2003/0227359 (2003-12-01), Ouchi
patent: 2004/0095207 (2004-05-01), Nakamura et al.
patent: 2004/0201435 (2004-10-01), Ouchi et al.
patent: 06-204781 (1994-07-01), None
patent: 11-97966 (1999-04-01), None
patent: 2001-308672 (2001-11-01), None
patent: 2002-111432 (2002-04-01), None
patent: 2003-092527 (2003-03-01), None
patent: 2003-115746 (2003-04-01), None
patent: 3419402 (2003-04-01), None
patent: 2003-179462 (2003-06-01), None
patent: 2003-243965 (2003-08-01), None
patent: 2004-48675 (2004-02-01), None
International Search Report issued in the corresponding International Application No. PCT/JP2005/014672, mailed on Dec. 13, 2005.
Keating & Bennett LLP
Murata Manufacturing Co. Ltd.
Summons Barbara
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