Laminated dielectric filter, and antenna duplexer and communication equipment using the same

Claim 2

A filter, comprising a plurality of resonators, the resonators being coupled to one another by electromagnetic-field coupling, wherein non-adjacent resonators of said plurality of resonators are electrically coupled to each other with a bypass circuit formed of a bypass capacitor and a non-grounded transmission line, the bypass circuit functioning as a capacitive coupling parallel to a magnetic-field bypass coupling between non-adjacent resonators; wherein adjacent resonators of said plurality of resonators are electrically coupled to each other with a series circuit formed of an inter-stage capacitor and a transmission line, each series circuit functioning as a capacitive coupling parallel to a magnetic-field coupling between the adjacent resonators; wherein the plurality of resonators and the transmission line are formed inside a dielectric body.

Claim 3

A dielectric filter, comprising: a plurality of resonator electrodes formed of at least three front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which has portions opposing respective portions of two adjacent resonator electrodes included in the plurality of resonator electrodes, the plurality of inter-stage coupling capacitor electrodes each functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; a plurality of loading capacitor electrodes having portions opposing portions of the plurality of inter-stage capacitor electrodes, respectively for regulating resonance frequencies of the resonator electrodes; and a bypass electrode having portions opposing portions of the plurality of inter-stage capacitor electrodes, the bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes.

Claim 4

A dielectric filter, comprising: a plurality of resonator electrodes formed of at least three front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which has portions opposing respective portions of two adjacent resonator electrodes included in the plurality of resonator electrodes, the plurality of inter-stage coupling capacitor electrodes each functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; a plurality of loading capacitor electrodes having portions opposing portions of the plurality of inter-stage capacitor electrodes, respectively for regulating resonance frequencies of the resonator electrodes; and a bypass electrode having portions opposing portions of the plurality of inter-stage capacitor electrodes, the bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes.

Claim 5

The dielectric filter according to claim 2 , wherein the plurality of resonator electrodes, the plurality of inter-stage coupling capacitor electrodes, the bypass electrode, and the plurality of loading capacitor electrodes are formed between a plurality of shield electrodes, and the plurality of shield electrodes are connected to each other, and then are grounded.

Claim 6

The dielectric filter according to claim 2 , wherein loading capacitor electrodes of the plurality of loading capacitor electrodes oppose open ends of the plurality of resonator electrodes and are grounded.

Claim 7

A dielectric filter, comprising: a plurality of shield electrodes formed on outer faces of a dielectric body; a plurality of resonator electrodes formed of at least three front end short-circuit ¼ wavelength transmission lines; a plurality of first capacitor electrodes, each of which has portions opposing respective portions of two adjacent resonator electrodes included in the plurality of resonator electrodes; a plurality of second capacitor electrodes having portions opposing portions of the plurality of first capacitor electrodes, respectively; and a bypass electrode having portions opposing portions of the first capacitor electrodes, the bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the plurality of resonator electrodes, the plurality of first capacitor electrodes, the bypass electrode, and the plurality of second capacitor electrodes are formed between the plurality of shield electrodes; wherein the dielectric filter includes a plurality of input/output coupling capacitor electrodes opposing resonator electrodes of the plurality of resonator electrodes on outermost sides, and the plurality of input/output coupling capacitor electrodes are connected to a plurality of side electrodes to form input/output terminals.

Claim 8

A dielectric filter, comprising: a plurality of shield electrodes formed on outer faces of a dielectric body; a plurality of resonator electrodes formed of at least three front end short-circuit ¼ wavelength transmission lines; a plurality of first capacitor electrodes, each of which has portions opposing respective portions of two adjacent resonator electrodes included in the plurality of resonator electrodes; a plurality of second capacitor electrodes having portions opposing portions of the plurality of first capacitor electrodes, respectively; and a bypass electrode having portions opposing portions of the first capacitor electrodes, the bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the plurality of resonator electrodes, the plurality of first capacitor electrodes, the bypass electrode, and the plurality of second capacitor electrodes are formed between the plurality of shield electrodes; wherein the dielectric filter includes a plurality of input/output coupling capacitor electrodes opposing resonator electrodes of the plurality of resonator electrodes on outermost sides, and the plurality of input/output coupling capacitor electrodes are connected to a plurality of side electrodes to form input/output terminals.

Claim 9

A laminated dielectric filter, comprising: a first dielectric layer; a second dielectric layer; a third dielectric layer; a fourth dielectric layer; a first shield electrode; a second shield electrode; at least three resonator electrodes comprising front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which is formed of a transmission line having portions opposing respective portions of two adjacent resonator electrodes of said at least three resonator electrodes, the plurality of inter-stage coupling capacitor electrodes each functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; and a non-grounded bypass electrode having portions opposing the plurality of inter-stage coupling capacitor electrode, the non-grounded bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the first dielectric layer is laminated above the first shield electrode, the resonator electrodes are formed on an upper surface of the first dielectric layer, the second dielectric layer is laminated above the resonator electrodes, the inter-stage coupling capacitor electrodes are formed on an upper surface of the second dielectric layer, the third dielectric layer is laminated above the inter-stage coupling capacitor electrodes, the non-grounded bypass electrode is formed on an upper surface of the third dielectric layer, the fourth dielectric layer is laminated above the non-grounded bypass electrode, and the second shield electrode is positioned on an upper surface of the fourth dielectric layer.

Claim 10

A laminated dielectric filter, comprising: a first dielectric layer; a second dielectric layer; a third dielectric layer; a fourth dielectric layer; a first shield electrode; a second shield electrode; at least three resonator electrodes comprising front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which is formed of a transmission line having portions opposing respective portions of two adjacent resonator electrodes of said at least three resonator electrodes, the plurality of inter-stage coupling capacitor electrodes each functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; and a non-grounded bypass electrode having portions opposing the plurality of inter-stage coupling capacitor electrode, the non-grounded bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the first dielectric layer is laminated above the first shield electrode, the resonator electrodes are formed on an upper surface of the first dielectric layer, the second dielectric layer is laminated above the resonator electrodes, the inter-stage coupling capacitor electrodes are formed on an upper surface of the second dielectric layer, the third dielectric layer is laminated above the inter-stage coupling capacitor electrodes, the non-grounded bypass electrode is formed on an upper surface of the third dielectric layer, the fourth dielectric layer is laminated above the non-grounded bypass electrode, and the second shield electrode is positioned on an upper surface of the fourth dielectric layer.

Claim 11

The laminated dielectric filter according to claim 6 , further comprising loading capacitor electrodes formed of transmission lines opposing open ends of the resonator electrodes, wherein said loading capacitor electrodes are grounded.

Claim 12

The laminated dielectric filter according to claim 6 , further comprising a plurality of input/output coupling capacitor electrodes opposing the resonator electrodes on outermost sides, wherein the plurality of input/output coupling capacitor electrodes are connected to side electrodes to form input/output terminals.

Claim 13

The laminated dielectric filter according to claim 6 , wherein the first shield electrode is provided on an upper surface of a fifth dielectric layer.

Claim 14

The laminated dielectric filter according to claim 6 , further comprising a sixth dielectric layer laminated above the second shield electrode.

Claim 15

The laminated dielectric filter according to claim 6 , wherein the first shield electrode and the second shield electrode are connected and then are grounded.

Claim 16

An antenna duplexer, comprising a dielectric filter including: a plurality of resonator electrodes formed of at least three front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which has portions opposing respective portions of two adjacent resonator electrodes included in the plurality of resonator electrodes, the plurality of inter-stage coupling capacitor each electrodes functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; a plurality of loading capacitor electrodes having portions opposing portions of the plurality of inter-stage coupling capacitor electrodes, respectively for regulating resonance frequencies of the resonator electrodes; and a bypass electrode having portions opposing portions of the plurality of inter-stage coupling capacitor electrodes, the bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the dielectric filter is used as one of or both of filters on transmission and reception sides.

Claim 17

An antenna duplexer, comprising a dielectric filter including: a plurality of resonator electrodes formed of at least three front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which has portions opposing respective portions of two adjacent resonator electrodes included in the plurality of resonator electrodes, the plurality of inter-stage coupling capacitor each electrodes functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; a plurality of loading capacitor electrodes having portions opposing portions of the plurality of inter-stage coupling capacitor electrodes, respectively for regulating resonance frequencies of the resonator electrodes; and a bypass electrode having portions opposing portions of the plurality of inter-stage coupling capacitor electrodes, the bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the dielectric filter is used as one of or both of filters on transmission and reception sides.

Claim 18

An antenna duplexer, comprising a laminated dielectric filter including: a first dielectric layer; a second dielectric layer; a third dielectric layer; a fourth dielectric layer; a first shield electrode; a second shield electrode; at least three resonator electrodes comprising front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which is formed of a transmission line having portions opposing respective portions of two adjacent resonator electrodes of said at least three resonator electrodes, the plurality of inter-stage coupling capacitor electrodes each functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; and a non-grounded bypass electrode having portions opposing the plurality of inter-stage coupling capacitor electrodes and not grounded, the non-grounded bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the first dielectric layer is laminated above the first shield electrode, the resonator electrodes are formed on an upper surface of the first dielectric layer, the second dielectric layer is laminated above the resonator electrodes, the inter-stage coupling capacitor electrodes are formed on an upper surface of the second dielectric layer, the third dielectric layer is laminated above the inter-stage coupling capacitor electrodes, the non-grounded bypass electrode is formed on an upper surface of the third dielectric layer, the fourth dielectric layer is laminated above the non-grounded bypass electrode, and the second shield electrode is positioned on an upper surface of the fourth dielectric layer; and the laminated dielectric filter is used as one of or both of filters on transmission and reception sides.

Claim 19

An antenna duplexer, comprising a laminated dielectric filter including: a first dielectric layer; a second dielectric layer; a third dielectric layer; a fourth dielectric layer; a first shield electrode; a second shield electrode; at least three resonator electrodes comprising front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which is formed of a transmission line having portions opposing respective portions of two adjacent resonator electrodes of said at least three resonator electrodes, the plurality of inter-stage coupling capacitor electrodes each functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; and a non-grounded bypass electrode having portions opposing the plurality of inter-stage coupling capacitor electrodes and not grounded, the non-grounded bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the first dielectric layer is laminated above the first shield electrode, the resonator electrodes are formed on an upper surface of the first dielectric layer, the second dielectric layer is laminated above the resonator electrodes, the inter-stage coupling capacitor electrodes are formed on an upper surface of the second dielectric layer, the third dielectric layer is laminated above the inter-stage coupling capacitor electrodes, the non-grounded bypass electrode is formed on an upper surface of the third dielectric layer, the fourth dielectric layer is laminated above the non-grounded bypass electrode, and the second shield electrode is positioned on an upper surface of the fourth dielectric layer; and the laminated dielectric filter is used as one of or both of filters on transmission and reception sides.

Claim 20

Communication equipment, comprising a dielectric filter including: a plurality of resonator electrodes formed of at least three front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which has portions opposing respective portions of two adjacent resonator electrodes included in the plurality of resonator electrodes, the plurality of inter-stage coupling capacitor each electrodes functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; a plurality of loading capacitor electrodes having portions opposing portions of the plurality of inter-stage coupling capacitor electrodes, respectively for regulating resonance frequencies of the resonator electrodes; and a bypass electrode having portions opposing portions of the plurality of inter-stage coupling capacitor electrodes, the bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes.

Claim 21

Communication equipment, comprising a dielectric filter including: a plurality of resonator electrodes formed of at least three front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which has portions opposing respective portions of two adjacent resonator electrodes included in the plurality of resonator electrodes, the plurality of inter-stage coupling capacitor each electrodes functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; a plurality of loading capacitor electrodes having portions opposing portions of the plurality of inter-stage coupling capacitor electrodes, respectively for regulating resonance frequencies of the resonator electrodes; and a bypass electrode having portions opposing portions of the plurality of inter-stage coupling capacitor electrodes, the bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes.

Claim 22

Communication equipment, comprising a laminated dielectric filter including: a first dielectric layer; a second dielectric layer; a third dielectric layer; a fourth dielectric layer; a first shield electrode; a second shield electrode; at least three resonator electrodes comprising front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which is formed of a transmission line having portions opposing respective portions of two adjacent resonator electrodes of said at least three resonator electrodes, the plurality of inter-stage coupling capacitor electrodes each functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; and a non-grounded bypass electrode having portions opposing the plurality of inter-stage coupling capacitor electrodes and not grounded, the non-grounded bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the first dielectric layer is laminated above the first shield electrode, the resonator electrodes are formed on an upper surface of the first dielectric layer, the second dielectric layer is laminated above the resonator electrodes, the inter-stage coupling capacitor electrodes are formed on an upper surface of the second dielectric layer, the third dielectric layer is laminated above the inter-stage coupling capacitor electrodes, the non-grounded bypass electrode is formed on an upper surface of the third dielectric layer, the fourth dielectric layer is laminated above the non-grounded bypass electrode, and the second shield electrode is positioned on an upper surface of the fourth dielectric layer.

Claim 23

Communication equipment, comprising a laminated dielectric filter including: a first dielectric layer; a second dielectric layer; a third dielectric layer; a fourth dielectric layer; a first shield electrode; a second shield electrode; at least three resonator electrodes comprising front end short-circuit ¼ wavelength transmission lines; a plurality of inter-stage coupling capacitor electrodes, each of which is formed of a transmission line having portions opposing respective portions of two adjacent resonator electrodes of said at least three resonator electrodes, the plurality of inter-stage coupling capacitor electrodes each functioning as a capacitive coupling parallel to a magnetic-field coupling between the two adjacent resonator electrodes; and a non-grounded bypass electrode having portions opposing the plurality of inter-stage coupling capacitor electrodes and not grounded, the non-grounded bypass electrode functioning as a bypass circuit parallel to a magnetic-field bypass coupling between two non-adjacent resonator electrodes, wherein the first dielectric layer is laminated above the first shield electrode, the resonator electrodes are formed on an upper surface of the first dielectric layer, the second dielectric layer is laminated above the resonator electrodes, the inter-stage coupling capacitor electrodes are formed on an upper surface of the second dielectric layer, the third dielectric layer is laminated above the inter-stage coupling capacitor electrodes, the non-grounded bypass electrode is formed on an upper surface of the third dielectric layer, the fourth dielectric layer is laminated above the non-grounded bypass electrode, and the second shield electrode is positioned on an upper surface of the fourth dielectric layer.