Reduced length metallized ceramic duplexer

A duplexing communication signal filter for connection to an antenna, a transmitter and a receiver, the signal filter suitable for filtering an incoming signal from the antenna to the receiver and for filtering an outgoing signal from the transmitter to the antenna, the filter comprising:

• a first and a second rigid core of dielectric material, each core having a substantially rectangular parallelepided shape with a top surface, a bottom surface and four side surfaces and each core defining a series of through-holes, each through-hole extending from an opening on the top surface to an opening on the bottom surface;
• a first surface-layer pattern of metallized and unmetallized areas on the first core and including a first wide area of metallization for providing off-band signal absorption, a first unmetallized area substantially surrounding at least two of the openings on the top surface of the first core, a first bridge electrode extending between the top surface and the bottom surface, a transmitter connection pad of metallization for receiving the outgoing signal, and an antenna connection pad for receiving the incoming signal and outputting the outgoing signal;
• a second surface-layer pattern of metallized and unmetallized areas on the second core and including a second wide area of metallization for providing off-band signal absorption, a second unmetallized area substantially surrounding at least two of the openings on the top surface of the second core, a second bridge electrode extending between the top surface and the bottom surface, a receiver connection pad of metallization for providing the incoming signal;
• and
• a bond between each said bottom surface for joining the first core and the second core.

A duplexing communication signal filter for connection to an antenna, a transmitter and a receiver, the filter for filtering an incoming signal from the antenna to the receiver and for filtering an outgoing signal from the transmitter to the antenna, the filter comprising:

• a first and a second rigid core of dielectric material, each core having a substantially rectangular parallelepided shape with a top surface, a bottom surface and four side surfaces and each core defining a series of through-holes, each through-hole extending from an opening on the top surface to an opening on the bottom surface;
• a first surface-layer pattern of metallized and unmetallized areas on the first core and including a first wide area of metallization for providing off-band signal absorption, a first unmetallized area substantially surrounding at least two of the openings on the top surface of the first core, a first bridge electrode extending between the top surface and the bottom surface, and a transmitter connection pad of metallization for receiving the outgoing signal;
• a second surface-layer pattern of metallized and unmetallized areas on the second core and including a second wide area of metallization for providing off-band signal absorption, a second unmetallized area substantially surrounding at least two of the openings on the top surface of the second core, a second bridge electrode extending between the top surface and the bottom surface, a receiver connection pad of metallization for providing the incoming signal, and an antenna connection pad for receiving the incoming signal and outputting the outgoing signal, the second bridge electrode being conductively linked to the first bridge electrode;
• and
• a bond between each said bottom surface for joining the first core and the second core.

A duplexing communication signal filter for connection to an antenna, a transmitter and a receiver, the signal filter for filtering an incoming signal from the antenna to the receiver and for filtering an outgoing signal from the transmitter to the antenna, the filter comprising:

• a substantially U-shaped core of dielectric material including a first arm, a second arm and a base portion joining the first arm to the second arm, each arm having an inwardly facing surface and an outwardly facing surface and each arm defining a series of through-holes, each through-hole extending through the arm between an opening on the inwardly facing surface and an opening on the outwardly facing surface;
• and
• a pattern of metallized and unmetallized areas on the core including,
• a wide area of metallization for providing off-band signal absorption,
• a first unmetallized area surrounding at least one of the through-hole openings on the outwardly facing surface of the transmit arm,
• a second unmetallized area surrounding at least one of the through-hole openings on the outwardly facing surface of the receiver arm,
• a transmitter pad metallized area on the first arm for receiving the outgoing signal,
• a receiver pad metallized area on the second arm for providing the incoming signal,
• an antenna pad metallized area on the base portion for receiving the incoming signal and outputting the outgoing signal, and
• a bridge metallized area extending between the first arm outwardly facing surface and the second arm outwardly facing surface.

A duplexing communication signal filter adapted for connection to an antenna, a transmitter and a receiver for filtering an incoming signal from the antenna to the receiver and for filtering an outgoing signal from the transmitter to the antenna, the filter comprising:

• a substantially U-shaped core of dielectric material including a first arm a second arm and a base portion joining the first arm to the second arm, each arm defining a series of through-holes extending through the arm;
• and
• a surface pattern of metallized and unmetallized areas on the core including,
• a wide area of metallization for providing off-band signal absorption,
• a first unmetallized area surrounding at least one of the through-holes of the transmit arm,
• a second unmetallized area surrounding at least one of the through-holes,
• a transmitter pad metallized area on the first arm for receiving the outgoing signal,
• a receiver pad metallized area on the second arm for providing the incoming signal,
• an antenna pad metallized area on the base portion for receiving the incoming signal and outputting the outgoing signal, and
• a bridge metallized area extending between the first arm and the second arm being capacitively coupled to the antenna pad.

A duplexing communication signal filter for connection to an antenna, a transmitter and a receiver, the signal filter suitable for filtering an incoming signal from the antenna to the receiver and for filtering an outgoing signal from the transmitter to the antenna, the filter comprising:

• a substantially rectangular parallelepiped shaped core of rigid dielectric material defining a slot dividing the core into a transmit branch and a receive branch such that each branch has an inwardly facing surface and an outwardly facing surface, each branch defines a series of through-holes, each through-hole extending through the branch between an opening on the inwardly facing surface and an opening the outwardly facing surface;
• and
• a pattern of metallized and unmetallized areas on the core including,
• a wide area of metallization for providing off-band signal absorption,
• a first unmetallized area surrounding a plurality of the through-hole openings on the outwardly facing surface of the transmitter branch,
• a second unmetallized area surrounding a plurality of the through-hole openings on the outwardly facing surface of the receiver branch,
• a transmitter pad metallized area on the transmit branch for receiving the outgoing signal,
• a receiver pad metallized area on the receive branch for providing an incoming signal,
• an antenna pad metallized area on the base portion for receiving the incoming signal and outputting the outgoing signal, and
• a bridge metallized area extending between the transmit branch outwardly facing surface and the receive arm outwardly facing surface.