Multiple resonator dielectric filter

• US 4,954,796 A
• Filed: 08/10/1988
• Issued: 09/04/1990
• Est. Priority Date: 07/25/1986
• Status: Expired due to Term

• Current Assignee: CTS Corporation
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Green, Steven R., De Muro, David M., Sokola, Raymond L., Gordon, Phillip J., Moutrie, Michael F.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Ham, Seung
• Application Number:
  US07/230,408
• Time in Patent Office: 755 Days
• Field of Search: 333/202, 333/204, 333/1, 333/207, 333/219, 333/219.1, 333/222, 333/223, 333/245, 333/246, 455/73, 455/78, 455/1, 455/83, 370/30, 370/36, 370/38
• US Class Current: 333/206
• CPC Class Codes: H01P 1/2056 Comb filters or interdigital filters with metallised resonator holes in a dielectric block

Abstract

A duplexer for a radio transceiver is disclosed in which two volumes of dielectric material each have at least two holes and each is covered with a conductive material except for one surface. An electrode on the one surface of each volume is coupled to one of the holes and is coupled to a substrate via a terminal passing through a mounting device. The substrate provides coupling between the terminals of the two volumes and a common antenna.

Claims

1. A duplex radio transceiver coupled to one antenna for both receive and transmit functions, comprising:

a transmitter;

a receiver;

a duplexer filter disposed between said transmitter and the antenna, and between said receiver and the antenna, said duplexer filter further comprising;

(a) at least two volumes of dielectric material, each volume of dielectric material having first, second, and side surfaces, said second and side surfaces of each volume of dielectric material being substantially covered with a conductive material;

(b) a plurality of holes extending through each said volume of dielectric material from said first surface to said second surface, the surface of at least two of said holes through each of said volume of dielectric material being substantially covered with a conductive material which is electrically common at said second surface of each respective volume of dielectric material, thereby forming at least two resonators in each said volume of dielectric material;

(c) first means for coupling a first of said at least two resonators of a first one of said at least two volumes of dielectric material to a first input/output terminal;

(d) second means for coupling a second of said at least two resonators of a first one of said at least two volumes of dielectric material to a second input/output terminal;

(e) third means for coupling a first of said at least two resonators of a second one of said at least two volumes of dielectric material to a third input/output terminal;

(f) fourth means for coupling a second of said at least two resonators of a second one of said at least two volumes of dielectric material to a fourth input/output terminal;

(g) mounting means comprising a conductive material for supporting at least one of said volumes of dielectric material on a substrate; and

(h) a first transmission line disposed on said substrate and coupling said first input/output terminal to said third input/output terminal and to the antenna whereby receiver signals from the antenna may be rejected by said first volume of dielectric material and transmitter signals from the transmitter may be rejected by said second volume of dielectric material.

2. A duplex radio transceiver in accordance with claim 1 further comprising:

a second transmission line disposed on said substrate and coupling said second input/output terminal to the radio transceiver transmitter; and

a third transmission line disposed on said substrate and coupling said fourth input/output terminal to the radio transceiver receiver.

3. A duplexer filter for a radio transceiver employing one antenna for both receiving and transmitting radio signals, comprising:

a first volume of dielectric material having at least two holes extending from a first external surface of a plurality of external surfaces of said first volume toward a second external surface of said plurality of external surfaces of said first volume, all surfaces of said first volume including surfaces within said at least two holes being substantially covered with a conductive material with the exception of said first external surface upon which surface is disposed at least one electrode coupled to said conductive material of one of said at least two hole surfaces;

a second volume of dielectric material having at least two holes extending from a first external surface of a plurality of external surfaces of said second volume toward a second external surface of said plurality of external surfaces of said second volume, all surfaces of said second volume including surfaces within said at least two holes being substantially covered with a conductive material with the exception of said first external surface upon which surface is disposed at least one electrode coupled to said conductive material of one of said at least two hole surfaces;

first mounting means comprising;

(a) a conductive material having a recessed area for accepting and holding said first volume of dielectric material and an interior surface within said recessed area disposed essentially parallel to one of said plurality of external surfaces of said first volume of dielectric material,

(b) a terminal extending through said interior surface and providing electrical contact to said electrode, and

(c) a plurality of mounting tabs disposed at predetermined positions opposite said recessed area for affixing said first volume of dielectric material to a substrate; and

coupling means disposed on said substrate for coupling said terminal of said first volume to said second volume whereby receiver signals from the antenna may be rejected by one of said first and second volumes and transmitter signals from the radio transceiver transmitter may be rejected by another of said first and second volumes.

4. A duplexer filter for a radio transceiver employing one antenna for both receiving and transmitting radio signals, comprising:

a first volume of dielectric material having at least two holes extending from a first external surface of a plurality of external surfaces of said first volume toward a second external surface of said plurality of external surfaces of said first volume, all surfaces of said first volume including surfaces within said at least two holes being substantially covered with a conductive material with the exception of said first external surface upon which surface is disposed at least one electrode coupled to said conductive material of one of said at least two hole surfaces;

a second volume of dielectric material having at least two holes extending from a first external surface of a plurality of external surfaces of said second volume toward a second external surface of said plurality of external surfaces of said second volume, all surfaces of said second volume including surfaces within said at least two holes being substantially covered with a conductive material with the exception of said first external surface upon which surface is disposed at least one electrode coupled to said conductive material of one of said at least two hole surfaces;

first mounting means comprising;

(a) a conductive material having a recessed area for accepting and holding said second volume of dielectric material and an interior surface within said recessed area disposed essentially parallel to one of said plurality of external surfaces of said second volume of dielectric material,

(b) a terminal extending through said interior surface and providing electrical contact to said electrode, and

(c) a plurality of mounting tabs disposed at predetermined positions opposite said recessed area for affixing said second volume of dielectric material to a substrate; and

coupling means disposed on said substrate for coupling said terminal of said second volume to said first volume whereby receiver signals from the antenna may be rejected by one of said first and second volumes and transmitter signals from the radio transceiver transmitter may be rejected by another of said first and second volumes.

5. A duplexer filter for a radio transceiver employing one antenna for both receiving and transmitting radio signals, comprising:

a first volume of dielectric material having at least two holes extending from a first external surface of a plurality of external surfaces of said first volume toward a second external surface of said plurality of external surfaces of said first volume, all surfaces of said first volume including surfaces within said at least two holes being substantially covered with a conductive material with the exception of said first external surface upon which surface are disposed first and second electrodes coupled to said first and second hole surface conductive materials, respectively, thereby forming resonators which may be tun ed to a receiver frequency;

a second volume of dielectric material having at least two holes extending from a first external surface of a plurality of external surfaces of said second volume toward a second external surface of said plurality of external surfaces of said second volume, all surfaces of said second volume including surfaces within said at least two holes being substantially covered with a conductive material with the exception of said first external surface upon which surface are disposed first and second electrodes coupled to said first and second hole surface conductive materials, respectively, thereby forming resonators which may be tuned to a transmitter frequency;

first mounting means comprising;

(a) a conductive material having a recessed area for accepting and holding said first volume of dielectric material and an interior surface within said recessed area disposed essentially parallel to one of said plurality of external surfaces of said first volume of dielectric material,

(b) first and second terminal means extending through said interior surface and providing electrical contact respectively to said first and second electrodes, and

(c) a plurality of mounting tabs disposed at predetermined positions opposite said recessed area for affixing said first volume of dielectric material to said substrate;

second mounting means comprising;

(a) a conductive material having a recessed area for accepting and holding said second volume of dielectric material and an interior surface within said recessed area disposed essentially parallel to one of said plurality of external surfaces of said second volume of dielectric material,

(b) first and second terminal means extending through said interior surface and providing electrical contact respectively to said first and second electrodes, and

(c) a plurality of mounting tabs disposed at predetermined positions opposite said recessed area for affixing said second volume of dielectric material to said substrate; and

first coupling means disposed on a common substrate for coupling said first electrode of said first volume to said first electrode of said second volume whereby receiver signals from the antenna may be rejected by said second volume and transmitter signals from the transmitter may be rejected by said first volume.

6. A duplexer filter in accordance with claim 5 further comprising:

second coupling means disposed on said substrate for coupling said second terminal of said first mounting means to the radio transceiver receiver; and

third coupling means disposed on said substrate for coupling said second terminal of said second mounting means to the radio transceiver transmitter.

7. A duplexer filter for a radio transceiver employing at least one antenna for both receiving and transmitting radio signals, comprising:

a first filter comprising a plurality of resonators, at least one of said plurality of resonators formed from at least one hole in a dielectric material being substantially covered with a conductive material and extending from a first external surface of said dielectric material to a second external surface, said dielectric material being substantially covered with a conductive material with the exception of said first external surface upon which surface is disposed at least one electrode coupled to said conductive material of said at least one hole;

a second filter comprising a plurality of resonators, at least one of said plurality of resonators formed from at least one hole in a dielectric material being substantially covered with a conductive material and extending from a first external surface of said dielectric material to a second external surface, said dielectric material being substantially covered with a conductive material with the exception of said first external surface upon which surface is disposed at least one electrode coupled to said conductive material of said at least one hole;

mounting means comprising;

(a) a conductive material having a recessed area for accepting and holding said first filter, an interior surface within said recessed area disposed essentially parallel to one of said two external surfaces of said dielectric material of said first filter,

(b) a terminal extending through said interior surface and coupled to said at least one electrode of said first filter, and

(c) a plurality of mounting tabs disposed at predetermined positions opposite said recessed area for affixing said first filter to a substrate; and

coupling means disposed on said substrate for coupling said terminal of said first filter to said second filter whereby receiver signals from the at least one antenna may be rejected by one of said first and second filters and transmitter signals from the radio transceiver transmitter may be rejected by another of said first and second filters.

8. A duplexer filter for a radio transceiver employing at least one antenna for both receiving and transmitting radio signals, comprising:

a first filter comprising a plurality of resonators, at least one of said plurality of resonators formed from at least one hole in a dielectric material being substantially covered with a conductive material an d extending from a first external surface of said dielectric material to a second external surface, said dielectric material being substantially covered with a conductive material with the exception of said first external surface upon which surface is disposed at least one electrode coupled to said conductive material of said at least one hole;

a second filter comprising a plurality of resonators, at least one of said plurality of resonators formed from at least one hole in a dielectric material being substantially covered with a conductive material and extending from a first external surface of said dielectric material to a second external surface, said dielectric material being substantially covered with a conductive material with the exception of said first external surface upon which surface is disposed at least one electrode coupled to said conductive material of said at least one hole;

mounting means comprising;

(a) a conductive material having a recessed area for accepting and holding said second filter, an interior surface within said recessed area disposed essentially parallel to one of said two external surfaces of said dielectric material of said second filter,

(b) a terminal extending through said interior surface and coupled to said at least one electrode of said second filter, and

(c) a plurality of mounting tabs disposed at predetermined positions opposite said recessed area for affixing said second filter to a substrate; and

coupling means disposed on said substrate for coupling said terminal of said second filter to said first filter whereby transmitter signals from the radio transceiver transmitter may be rejected by on e of said first and second filters and receiver signals from the at least one antenna may be rejected by another of said first and second filters.

9. A duplexer filter for a radio transceiver employing at least one antenna for both receiving and transmitting radio signals, comprising:

a first filter comprising a plurality of resonators, at least one of said plurality of resonators formed from a conductive material substantially covering the surface of at least one hole extending from a first external surface of a dielectric material to a second external surface of said dielectric material, said dielectric material being substantially covered with a conductive material with the exception of said first external surface, upon which surface is disposed at least one electrode coupled to said conductive material of said at least one hole;

a second filter comprising a plurality of resonators, at least one of said plurality of resonators formed from a conductive material substantially covering the surface of at least one hole extending from a first external surface of a dielectric material to a second external surface of said dielectric material, said dielectric material being substantially covered with a conductive material with the exception of said first external surface, upon which surface is disposed at least one electrode coupled to said conductive material of said at least one hole;

mounting means comprising;

(a) a conductive material having a recessed area for accepting and holding said first filter, an interior surface within said recessed area disposed essentially parallel to one of said two external surfaces of said dielectric material of said first filter, and

(b) a terminal extending through said interior surface and coupled to said at least one electrode of said first filter; and

coupling means disposed on a substrate for coupling said terminal of said first filter to said second filter whereby receiver signals from the at least one antenna may be rejected by one of said first and second filters and transmitter signals from the radio transceiver transmitter may be rejected by another of said first and second filters.

10. A duplexer filter for a radio transceiver employing at least one antenna for both receiving and transmitting radio signals, comprising:

a first filter comprising a plurality of resonators, at least one of said plurality of resonators formed from a conductive material substantially covering the surface of at least one hole extending from a first external surface of a dielectric material to a second external surface of said dielectric material, said dielectric material being substantially covered with a conductive material with the exception of said first external surface, upon which surface is disposed at least one electrode coupled to said conductive material of said at least one hole;

a second filter comprising a plurality of resonators, at least one of said plurality of resonators formed from a conductive material substantially covering the surface of at least one hole extending from a first external surface of a dielectric material to a second external surface of said dielectric material, said dielectric material being substantially covered with a conductive material with the exception of said first external surface, upon which surface is disposed at least one electrode coupled to said conductive material of said at least one hole;

mounting means comprising;

(a) a conductive material having a recessed area for accepting and holding said second filter, an interior surface within said recessed area disposed essentially parallel to one of said two external surfaces of said dielectric material of said second filter, and

(b) a terminal extending through said interior surface and coupled to said at least one electrode of said second filter; and

coupling means disposed on a substrate for coupling said terminal of said second filter to said first filter whereby transmitter signals from the radio transceiver transmitter may be rejected by one of said first and second filters and receiver signals from the at least one antenna may be rejected by another of said first and second filters.