Antenna duplexer having transmit and receive portion formed in a single dielectric block

• US 5,686,873 A
• Filed: 11/16/1994
• Issued: 11/11/1997
• Est. Priority Date: 11/18/1993
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Tada, Hitoshi, Kato, Hideyuki
• Primary Examiner(s): LEE, BENNY T
• Application Number:
  US08/340,542
• Time in Patent Office: 1,091 Days
• Field of Search: 333/134, 333/126, 333/129, 333/202, 333/206, 333/222, 333/202 DB
• US Class Current: 333/134
• CPC Class Codes: H01P 1/2136 using comb or interdigital filters; using cascaded coaxial cavities H01P1/2131, H01P1/2135 take precedence

Abstract

Resonator holes are formed extending one to the other of a pair of opposing end surfaces of a dielectric block, and inner conductors are formed on inner peripheral surfaces of resonator holes respectively. On an outer surface of dielectric block, a pair of input/output electrodes and one antennal electrode are formed, and expect these regions, an outer conductor is formed. By the coupling of two resonators corresponding to the resonator holes, a transmitting filter is provided, and by two resonators corresponding to resonator holes, a receiving filter is formed.

Claims

1. An antenna duplexer, comprising:

a dielectric block having a pair of opposing end surfaces;

a plurality of resonator holes respectively extending from one of said pair of end surfaces to the other of said pair of end surfaces of said dielectric block, each hole having a respective inner surface with a substantially constant cross-sectional shape along an axial direction of the corresponding hole;

an outer conductor disposed on outer peripheral surfaces and said opposing end surfaces of said dielectric block;

each resonator hole respectively having a pair of inner conductors disposed in the corresponding hole and conductively connected to said outer conductor at respective ends of said corresponding hole at opposing end surfaces of said dielectric block, a respective non-conductive portion at said inner surface of the corresponding hole being spaced from both ends of said respective hole and thus separating said respective pair of inner conductors to thereby define a corresponding capacitance between said respective pair of inner conductors, a surface of said respective non-conductive portion being substantially flush with said inner surface of the corresponding hole; and

a common antenna electrode and a pair of input/output electrodes disposed on said outer peripheral surface of said dielectric block, and each electrode being coupled to corresponding ones of said inner conductors, thereby coupling said plurality of resonator holes and said plurality of inner conductors into an arrangement functioning as a transmitting filter portion and as a receiving filter portion of said antenna duplexer;

wherein said outer peripheral surfaces comprise a pair of opposing side surfaces of said dielectric block and a planar surface of said dielectric block intersecting said pair of opposing side surfaces;

one of said pair of input/output electrodes being disposed in an area at a corner of one of said opposing side surfaces, and the other of said pair of input/output electrodes being disposed in an area at a corner of the other of said opposing side surfaces, and each of said pair of input/output electrodes respectively extending onto said planar surface of said dielectric block; and

said common electrode being disposed on said planar surface between said pair of input/output electrodes.

2. An antenna duplexer, comprising:

a dielectric block having a pair of opposing end surfaces;

a plurality of resonator holes respectively extending from one of said pair of end surfaces to the other of said pair of end surfaces of said dielectric block, each hole having a respective inner surface with a substantially constant cross-sectional shape along an axial direction of the corresponding hole;

an outer conductor disposed on outer peripheral surfaces and said opposing end surfaces of said dielectric block;

each resonator hole respectively having a pair of inner conductors disposed in the corresponding hole and conductively connected to said outer conductor at respective ends of said corresponding hole at opposing end surfaces of said dielectric block, a respective non-conductive portion at said inner surface of the corresponding hole being spaced from both ends of said respective hole and thus separating said respective pair of inner conductors to thereby define a corresponding capacitance between said respective pair of inner conductors, a surface of said respective non-conductive portion being substantially flush with said inner surface of the corresponding hole; and

a common antenna electrode and a pair of input/output electrodes disposed on said outer peripheral surface of said dielectric block, and each electrode being coupled to corresponding ones of said inner conductors, thereby coupling said plurality of resonator holes and said plurality of inner conductors into an arrangement functioning as a transmitting filter portion and as a receiving filter portion of said antenna duplexer;

wherein said dielectric block further has a through hole with an inner conductor disposed therein, said inner conductor of said through hole being electrically connected to said outer conductor and disposed in said dielectric block between said transmitting filter and said receiving filter, said inner conductor being parallel to said plurality of resonator holes, and thereby providing isolation between said transmitting filter and said receiving filter.

3. The antenna duplexer according to claim 2, further comprising

a connecting member for electrically connecting one end of the inner conductor of said through hole with said common electrode;

wherein

the inner conductor of said through hole being electrically connected to said outer conductor at the other end of said through hole.

4. The antenna duplexer according to claim 3, wherein an inductance is between said common electrode and said outer conductor, and said inductance being capable of absorbing reflected phases of said transmitting filter and said receiving filter.