Patent ID: 8497743

Claim:
A coupling circuit for coupling a transceiver to an antenna, said coupling circuit comprising: a coupling network comprising: a plurality of inputs providing quadriphase versions of at least one input signal including phase-inverted and non-phase-inverted In-phase signals and phase-inverted and non-phase-inverted Quadrature signals; and a plurality of outputs, each output coupled to at least one of a selected one of the phase-inverted and non-phase-inverted In-phase signals of each input and a selected one of the phase-inverted and non-phase-inverted Quadrature signals of each input such that: 1) a desired phase shift is produced between each input and each output; 2) the frequency response for a signal from any input to any output is substantially identical except for the desired phase shift; 3) an amount of coupling between a given In-phase signal and a given output is proportional to the cosine of the corresponding desired phase shift; and 4) an amount of coupling between a given Quadrature signal and a given output is proportional to the sine of the corresponding desired phase shift; wherein the coupling circuit comprises a plurality of stages connected in cascade, wherein each stage comprises one or more of the coupling networks.