Impedance matching circuit for power amplifier

An impedance matching circuit, comprising:

• an input port for receiving RF signals in at least a first frequency band and a second frequency band, a first output port, and a second output port;
• a first path for communicating RF signals in the first frequency band to said first output port;
• and
• a second path for communicating RF signals in the second frequency band to a second output port;
• wherein said first path includes first means for blocking RF signals in the second frequency band from being communicated to said first output port and for matching the impedance between said input port and said first output port for RF signals in the first frequency band;
• and
• wherein said first path includes a reactive element which contributes to the impedance match of RF signals in said second frequency band;
• wherein said second path includes second means for blocking RF signals in the first frequency band from being communicated to said second output port;
• and
• wherein said first blocking means comprises a parallel resonant circuit selected to present an open circuit to signals in said second frequency band and said second blocking means includes a parallel resonant circuit selected to present substantially an open circuit to signals in said first frequency band, for blocking signals in said second frequency band from being communicated to said first output port and for blocking signals in said first frequency band from being communicated to said second output port, respectively.

An impedance matching circuit, comprising:

• an input port for receiving RF signals in at least a first frequency band and a second frequency band a first output port, and a second output port;
• a first path for communicating RF signals in the first frequency band to said first output port;
• and
• a second path for communicating RF signals in the second frequency band to a second output port;
• wherein said first path includes first means for blocking RF signals in the second frequency band from being communicated to said first output port and for matching the impedance between said input port and said first output port for RF signals in the first frequency band;
• and
• wherein said first path includes a reactive element which contributes to the impedance match of RF signals in said second frequency band;
• wherein said second path includes second means for blocking RF signals in the first frequency band from being communicated to said second output port;
• wherein said first blocking means comprises a series resonant circuit selected to present substantially a short circuit to signals in said second frequency band and said second blocking means comprises a parallel resonant circuit selected to present substantially an open circuit to signals in said first frequency band, for blocking signals in said second frequency band from being communicated to said first output port and for blocking signals in said first frequency band from being communicated to said second output port, respectively;
• and
• wherein said first path further comprises a series inductor and a shunt capacitor selected to provide a high pass filter network.

An impedance matching circuit, comprising:

• an input port for receiving RF signals in at least a first frequency band and a second frequency band, a first output port, and a second output port;
• a first path for communicating RF signals in the first frequency band to said first output port;
• and
• a second path for communicating RF signals in the second frequency band to a second output port;
• wherein said first path includes first means for blocking RF signals in the second frequency band from being communicated to said first output port and for matching the impedance between said input port and said first output port for RF signals in the first frequency band;
• and
• wherein said first path includes a reactive element which contributes to the impedance match of RF signals in said second frequency band;
• wherein said first path comprises a low pass filter;
• and
• wherein said second path comprises a low pass filter.

An impedance matching circuit comprising:

• an input port for receiving RF signals in at least a first frequency band and a second frequency band, a first output port, and a second output port;
• a first path for communicating RF signals in the first frequency band to said first output port;
• and
• a second path for communicating RF signals in the second frequency band to a second output port;
• wherein said first path includes first means for blocking RF signals in the second frequency band from being communicated to said first output port and for matching the impedance between said input port and said first output port for RF signals in the first frequency band;
• and
• wherein said first path includes a reactive element which contributes to the impedance match of RF signals in said second frequency band;
• wherein said second path includes second means for blocking RF signals in the first frequency band from being communicated to said second output port;
• and
• wherein said second blocking means comprises a parallel resonant circuit selected to present an open circuit to signals in said first frequency band,
• said second path includes a shunt circuit having an impedance selected such that said shunt circuit appears as a shunt inductance to RF signals in said second frequency band, and wherein said parallel resonant circuit and said shunt circuit operatively form a high pass impedance matching network for RF signals in said second frequency band.

An impedance matching circuit comprising:

• an input port for receiving RF signals in a first frequency band and a second frequency band, a first output port and a second output port;
• a first path for communicating RF signals in the first frequency band to said first output port;
• and
• a second path for communicating RF signals in the second frequency band to said second output port;
• wherein said first path comprises:
• a parallel resonant circuit tuned to present substantially an open circuit to RF signals within said second frequency band and a series inductance to RF signals within said first frequency band,
• a first shunt capacitor coupled to said input port, and
• a second shunt capacitor coupled to said first output port;
• wherein said parallel resonant circuit and said first and second shunt capacitors operatively form a low pass impedance matching network for RF signals in said first frequency range, and
• wherein said second path comprises:
• a first series capacitor coupled to said input port,
• a third shunt capacitor coupled to said second output port,
• a first series inductor coupled to said second output port, and
• a shunt series resonant circuit tuned to present a short circuit to RF signals in said first frequency band and a shunt inductance to RF signals in said second frequency band, said shunt series resonant circuit coupled between said first series capacitor and said first series inductor;
• wherein said first series capacitor, said first and third shunt capacitors, said series inductor and said shunt series resonant circuit operatively form an impedance matching network for RF signals in said second frequency range;
• and
• wherein said first series capacitor operatively contributes to the impedance match of said low pass matching network for RF signals in said first frequency band.

An impedance matching circuit comprising:

• an input port for receiving RF signals in a first frequency band and a second frequency band, a first output port and a second output port;
• a first path for communicating RF signals in the first frequency band to said first output port;
• and
• a second path for communicating RF signals in the second frequency band to said second output port;
• wherein said first path comprises:
• a parallel resonant circuit tuned to present substantially an open circuit to RF signals within said second frequency band and a series inductance to RF signals within said first frequency band,
• a first shunt capacitor coupled to said input port, and
• a second shunt capacitor coupled to said first output port;
• wherein said parallel resonant circuit and said first and second shunt capacitors operatively form a low pass impedance matching network for RF signals in said first frequency range, and
• wherein said second path comprises:
• a parallel resonant circuit tuned to present substantially an open circuit to RF signals within said first frequency band and a series capacitance to RF signals within said second frequency band, and
• a shunt circuit comprising an inductor and a capacitor coupled to said second output port;
• wherein said first shunt capacitor, said shunt circuit and said parallel resonant circuit operatively form an impedance matching network for RF signals in said second frequency band.

An impedance matching circuit comprising:

• an input port for receiving RF signals in a first frequency band and a second frequency band, a first output port and a second output port;
• a first path for communicating RF signals in the first frequency band to said first output port;
• and
• a second path for communicating RF signals in the second frequency band to said second output port;
• wherein said first path comprises:
• a first parallel resonant circuit tuned to present substantially an open circuit to RF signals within said second frequency band and a series inductance to RF signals within said first frequency band,
• a first shunt capacitor coupled to said input port, and
• a second shunt capacitor coupled to said first output port;
• wherein said first parallel resonant circuit and said first and second shunt capacitors operatively form a low pass impedance matching network for RF signals in said first frequency range, and
• wherein said second path comprises:
• a second parallel resonant circuit tuned to present substantially an open circuit to RF signals within said first frequency band and a series capacitance to RF signals within said second frequency band, and
• a series inductor coupled to said parallel resonant circuit and third shunt capacitor coupled to said second output port;
• wherein said first and third shunt capacitors, said series inductor and said second parallel resonant circuit operatively form an impedance matching network for RF signals in said second frequency band.