US Patent 10536128 Transmission-line-based impedance transformer with coupled sections

A transmission-line-based impedance transformer including first and second couplers, with each coupler including respective pairs of coupled signal conductors. The signal conductors are connected sequentially in series between an input port and an output port and may form a single spiral configuration. A signal conductor of one coupler may be connected in series between the two signal conductors of another coupler. The couplers have characteristic impedances between an input impedance and an output impedance. A signal conductor of a coupler may include first and second conductor portions disposed in respective spaced-apart parallel planes, with the other signal conductor of the coupler disposed physically directly between the first and second conductor portions. A transmission-line signal conductor in the spiral may be shielded from coupled signal conductors by ground conductors disposed in respective spaced-apart parallel planes on opposite sides of the shielded signal conductor.