High frequency power divider/combiner circuit including a rat-race coupler coupled by first and second coupling structures to first and second input/output ports

A high frequency power combiner circuit for obtaining an output signal on a basis of input signals, the circuit comprising:

• a rat race coupler configured to provide the output signal at an output port thereof on the basis of a signal at a first input thereof and on the basis of a at a second input thereof;
• a first coupling structure coupled to the first input thereof, to couple the first input thereof with a first signal input port;
• a second coupling structure coupled to the second input thereof, to couple the second input thereof with a second signal input port;
• and
• a termination port coupled through a resistor to ground,
• wherein a characteristic impedance of a first transmission line portion between the output port and the first input port thereof is greater than a nominal ring impedance of the rat race coupler, and wherein a characteristic impedance of a second transmission line portion between the output port and the second input port thereof is less than the nominal ring impedance thereof.

A high frequency power divider circuit for distributing an input signal to two or more signal output ports, the circuit comprising:

• a rat race coupler configured to couple an input signal provided at an input port thereof to a first output thereof and to a second output thereof;
• a first coupling structure coupled to the first output for coupling the first output with a first signal output port;
• and
• a second coupling structure coupled to the second output for coupling the second output with a second signal output port,
• wherein the first coupling structure and the second coupling structure are adapted to provide different phase shifts over frequency, and
• wherein further the first coupling structure comprises a phase shifter adapted to at least partially compensate for a frequency variation of a phase difference between signals at the first output of the rat race coupler and at the second output of the rat race coupler in a system configured to operate at a design frequency of the rat race coupler,
• wherein the second coupling structure comprises a pair of coupled transmission lines,
• wherein a first end of a first coupled transmission line of the pair of coupled transmission lines is coupled with the second output of the rat race coupler, wherein a second end of the first coupled transmission line of the pair of coupled transmission lines is coupled to a second end of a second coupled transmission line, which is adjacent to the second end of the first coupled transmission line of the pair of coupled transmission lines, and
• wherein the first end of the second coupled transmission line of the pair of coupled transmission lines is coupled to the second signal output port.

A high frequency power combiner circuit for obtaining an output signal on a basis of input signals, the circuit comprising:

• a rat race coupler, wherein the rat race coupler is configured to provide the output signal at an output port of the rat race coupler on the basis of the input signals at a first input thereof and at a second input thereof;
• a first coupling structure coupled to the first input of the rat race coupler, for coupling the first input of the rat race coupler with a first signal input port;
• wherein said first coupling structure is coupled to the rat race coupler at only one junction;
• and
• a second coupling structure coupled to the second input of the rat race coupler, for coupling the second input of the rat race coupler with a second signal input port,
• wherein the first coupling structure and the second coupling structure are adapted to provide different phase shifts over frequency, and
• wherein the first coupling structure comprises a phase shifter adapted to at least partially compensate for a difference of frequency variations of transmission characteristics from the first input port of the rat race coupler to the output port, and from the second input port of the rat race coupler to the output port in a system configured to operated at a design frequency of the rat race coupler.