Ceramic RF filter having improved third harmonic response
AssigneeCTS Corporation
InventorsAlexandre Rogozine, Brian Richard Matthews
Life of this patent
Estimating the term…
Abstract
A duplexing filter 10 suitable for use in a mobile communication system. The filter 10 has a core of dielectric material 12 with several through holes 30 that define resonators 25. The core 12 has metallized surfaces 16, 18, 20, 22 and 24 except for the top surface 14. Several metallized resonator pads 60 surround each of the through holes 30 on the top surface 14. A metallized serpentine region 61, 62 extends from one or more of the resonator pads 60 toward a side surface 18 of the core 12. The metallized serpentine region 61, 62 causes attenuation of a third harmonic frequency.
Claims22
A signal filter suitable for use in a mobile communication device, the filter comprising:
- a core of dielectric material having a top, a bottom and four side surfaces having vertical edges;
- a plurality of through holes extending from the top to the bottom surface, each through hole defining a resonator;
- a contiguous unmetallized area located on the top surface and extending to one of the side surfaces;
- a first metallized area located on the bottom surface, the side surfaces and on the inner surfaces of the through holes;
- a transmitter electrode, an antenna electrode and a receiver electrode, each located on the top surface and extending to one of the side surfaces;
- a plurality of metallized resonator pads adjacent each of the through holes on the top surface, the resonator pads being connected to the first metallized area at the inner surfaces of the through holes;
- and
- a metallized serpentine region extending from at least one of the resonator pads towards one of the side surfaces adapted to cause attenuation of a third harmonic frequency.
A signal filter suitable for use in a mobile communication device, the filter comprising:
- a core of dielectric material having a top, a bottom and four side surfaces having vertical edges;
- a plurality of through holes extending from the top to the bottom surface, each through hole defining a resonator;
- a contiguous unmetallized area located on the top surface and extending to one of the side surfaces;
- a first metallized area located on the bottom surface, the side surfaces and on the inner surfaces of the through holes;
- a transmitter electrode, an antenna electrode and a receiver electrode, each located on the top surface and extending to one of the side surfaces;
- a plurality of metallized resonator pads adjacent each of the through holes on the top surface, the resonator pads being connected to the first metallized area;
- and
- a metallized serpentine region extending from at least one of the resonator pads towards one of the side surfaces wherein the serpentine region forms a series resonant circuit to ground that attenuates the third harmonic frequency.
A duplexing communication signal filter adapted for connection to an antenna, a transmitter and a receiver for filtering an incoming signal from said antenna to said receiver and for filtering an outgoing signal from said transmitter to said antenna, the filter comprising:
- a rigid core of dielectric material with a top surface, a bottom surface and at least four side surfaces, said core defining a series of through holes, each through hole extending from an opening on said top surface to an opening on said bottom surface;
- a surface-layer pattern of metallized and unmetallized areas on said core, the pattern including:
- a wide area of metallization,
- a pad of metallization adjacent at least one of said through hole openings on said top surface and connected to said wide area of metallization at said through hole opening,
- a contiguous unmetallized area substantially surrounding said pad;
- a transmitter connection area of metallization,
- a receiver connection area of metallization spaced apart from said transmitter connection area,
- an antenna connection area of metallization positioned between said transmitter connection area and said receiver connection area,
- said pad having a narrow sinuous extension adapted to cause attenuation of a third harmonic frequency.
A signal filter comprising:
- a rigid core of dielectric material with a top surface, a bottom surface and at least four side surfaces, said core defining a series of through holes, each through hole extending from an opening on said top surface to an opening on said bottom surface;
- a surface-layer pattern of metallized and unmetallized areas on said core, the pattern including:
- a wide area of metallization for providing off-band signal absorption,
- a pad of metallization adjacent at least one of said through hole openings on said top surface, the pad being connected to said wide area of metallization at said through hole opening and having a narrow sinuous extension adapted to cause attenuation of a third harmonic frequency,
- a contiguous unmetallized area substantially surrounding said pad,
- an input connection area of metallization,
- an output connection area of metallization spaced apart from said input connection area.
A duplexing communication signal filter adapted for connection to an antenna, a transmitter and a receiver for faltering an incoming signal from said antenna to said receiver and for filtering an outgoing signal from said transmitter to said antenna, the filter comprising:
- a rigid core of dielectric material with a top surface, a bottom surface and at least four side surfaces, said core defining a series of through holes, each through hole extending from an opening on said top surface to an opening on said bottom surface;
- a surface-layer pattern of metallized and unmetallized areas on said core, the pattern including:
- a wide area of metallization,
- a pad of metallization adjacent at least one of said through hole openings on said top surface and connected to said wide area of metallization at said through hole opening,
- a contiguous unmetallized area substantially surrounding said pad;
- a transmitter connection area of metallization,
- a receiver connection area of metallization spaced apart from said transmitter connection area,
- an antenna connection area of metallization positioned between said transmitter connection area and said receiver connection area,
- said pad including an extension having a sinuous path and forming a series resonant circuit to ground that attenuates the third harmonic frequency.
A duplexing communication signal filter adapted for connection to an antenna, a transmitter and a receiver for filtering an incoming signal from said antenna to said receiver and for filtering an outgoing signal from said transmitter to said antenna, the filter comprising:
- a rigid core of dielectric material with a top surface, a bottom surface and at least four side surfaces, said core defining a series of through holes, each through hole extending from an opening on said top surface to an opening on said bottom surface;
- a surface-layer pattern of metallized and unmetallized areas on said core, the pattern including:
- a wide area of metallization,
- a pad of metallization adjacent at least one of said through hole openings on said top surface and connected to said wide area of metallization at said through hole opening,
- a contiguous unmetallized area substantially surrounding said pad;
- a transmitter connection area of metallization,
- a receiver connection area of metallization spaced apart from said transmitter connection area,
- an antenna connection area of metallization positioned between said transmitter connection area and said receiver connection area,
- said pad including an intricate extension having a serpentine shape adapted to cause attenuation of a third harmonic frequency.
Dependencies are inferred from the claim text.