High power broadband termination for k-band amplifier combiners

A termination for terminating broadband high-power microwave signals comprising:

• a microstrip line for transporting said microwave signals;
• an absorptive element disposed over said microstrip line for absorbing higher frequency portions of said microwave signals, said absorptive element being a molded plug of an absorptive material, said absorptive material being a carbon based material;
• a resistive termination coupling to said microstrip line for terminating lower frequency portions of said microwave signals, said resistive termination being a lumped element resistor;
• and
• a matching network inbetween said resistive termination and said absorptive element for matching said microwave signals to said resistive termination, said matching network being an open ended microstrip line.

A K-band power amplifier combiner comprising:

• a plurality of amplifiers;
• a plurality of branch line combiners for combining output signals from said amplifiers and providing an output signal, each branch line combiner having input ports, an output port and an isolated port, each input port coupled to an output of one of said amplifiers;
• and
• a termination for each branch line coupler for terminating broad band high power microwave signals present at said isolated port, said termination comprising:
• a microstrip line;
• an absorptive element disposed over said microstrip line for absorbing higher frequency portions of said microwave signals substantially above ten GHz;
• a resistive termination coupling to said microstrip line for terminating lower frequency portions of said microwave signals substantially below ten GHz;
• and
• a matching network inbetween said resistive termination and said absorptive element for matching said microwave signals to said resistive termination.

A K-band power amplifier combiner comprising:

• a plurality of amplifiers;
• a plurality of branch line combiners for combining output signals from said amplifiers and providing an output signal, each branch line combiner having input ports, an output port and an isolated port, each input port coupled to an output of one of said amplifiers;
• and
• a termination for each branch line coupler for terminating broad band high power microwave signals present at said isolated port, said termination comprising:
• a microstrip line for transporting said high power microwave signals;
• an absorptive element disposed over said microstrip line for absorbing higher frequency portions of said microwave signals substantially above ten GHz, said absorptive element being a molded plug of made from a carbon based absorptive material;
• a resistive termination coupling to said microstrip line for terminating lower frequency portions of said microwave signals substantially below ten GHz, said resistive termination being a lumped element resistor;
• and
• a matching network inbetween said resistive termination and said absorptive element for matching said microwave signals to said resistive termination, said matching network being an open ended microstrip line.

A method of combining amplified microwave signals comprising the steps of:

• combining amplified microwave signals in a plurality of branch line combiners to provide an output signal, each branch line combiner having input ports, an output port and an isolated port;
• and
• terminating microwave signals present at each of said isolated ports with a broadband high-power termination, said terminating step comprising the steps of:
• transporting said microwave signals present at said isolated port on a microstrip line;
• absorbing higher frequency portions of said microwave signals present at said isolated port with an absorptive element disposed over said microstrip line;
• terminating lower frequency portions of said microwave signals present at said isolated port with a resistive termination;
• and
• matching said microwave signals present at said isolated port to said resistive termination with a matching network located inbetween said resistive termination and said absorptive element.

A method of combining amplified microwave signals comprising the steps of:

• combining amplified microwave signals in a plurality of branch line combiners to provide an output signal, each branch line combiner having input ports, an output port and an isolated port;
• and
• terminating microwave signals present at each of said isolated ports with a broadband high-power termination, said terminating step comprising the steps of:
• transporting said microwave signals present at said isolated port on a microstrip line;
• absorbing higher frequency portions of said microwave signals present at said isolated port with an absorptive element disposed over said microstrip line, said higher frequency portions being substantially above ten GHz, said absorptive element being a molded plug of a carbon based absorptive material;
• terminating lower frequency portions of said microwave signals present at said isolated port with a resistive termination, said lower frequency portions being substantially below ten GHz, said resistive termination being a lumped element resistor;
• and
• matching said microwave signals present at said isolated port to said resistive termination with a matching network located inbetween said resistive termination and said absorptive element, said matching network being an open ended microstrip line.