Monolithic butler matrix for beamforming applications utilizing nonvolatile radio frequency switches and planar wideband couplers

A method, comprising:

• electrically coupling, by a system comprising at least one processor, a common radio frequency (RF) port of a nonvolatile RF switch to one or more selectable RF ports of the nonvolatile RF switch, wherein the common RF port is electrically coupled to a conductor, and wherein the one or more selectable RF ports are connected to the conductor via a phase change alloy material junction between the selectable RF port and the conductor, the electrically coupling comprising:
• determining which of the one or more selectable RF ports to electrically couple to the common RF port via the conductor;
• for each selectable RF port determined to be a selectable RF port to electrically couple to the common RF port,
• determining whether the phase change alloy material junction between the selectable RF port and the conductor is in a conductive state or a nonconductive state, and, in response to the phase change alloy material junction being determined to be in the nonconductive state, controlling a heating element corresponding to the selectable RF port to change the phase change alloy material junction to a conductive state that electrically couples the selectable RF port to the conductor and a Butler matrix coupled to the conductor;
• and
• for each selectable RF port determined not to be a selectable RF port to electrically couple to the common RF port,
• determining whether the phase change alloy material junction between the selectable RF port and the conductor is in a conductive state or a nonconductive state, and, in response to the phase change alloy material junction being determined to be in a conductive state, controlling a heating element corresponding to the selectable RF port to change the phase change alloy material junction to the nonconductive state that electrically decouples the selectable RF port from the conductor and the Butler matrix.

A device, comprising:

• a Butler matrix comprising a top metallization layer corresponding to a metal layer above a substrate, and metal ground plane beneath the substrate, the Butler matrix comprising quadrature couplers, crossover couplers and delay elements integrated into the top metallization layer,
• wherein each quadrature coupler of the quadrature coupler comprises:
• a metallic upper plane in the top metallization layer,
• a first port coupled to the metallic upper plane via a first microstrip line, a second port coupled to the metallic upper plane via a second microstrip line, a third port coupled to the metallic upper plane via a third microstrip line, and a fourth port coupled to the metallic upper plane via a fourth microstrip line, wherein the first port is opposite the third port, the first port is adjacent to the second port, and the first port is the adjacent to fourth port,
• a first slot in the metallic upper plane having a first slot width and a first slot length, and
• a second slot in the metallic upper plane having a second slot width and a second slot length, wherein the first slot crosses the second slot at an intersection point, and wherein each crossover coupler of the crossover couplers comprises:
• a fifth port, a sixth port, a seventh port, and an eighth port,
• wherein the fifth port is coupled to a first segment of a fifth microstrip line and the seventh port is coupled to a third segment of the fifth microstrip line, and wherein the sixth port is coupled to a second segment of a sixth microstrip line and the fourth port is coupled to a fourth segment of the sixth microstrip line, and
• wherein the fifth microstrip line and the sixth microstrip line cross at an intersection point in a cross-shaped pattern,
• inner partial couplers surrounding the intersection point, comprising a first inner partial coupler between the first segment and the fourth segment, a second inner partial coupler between the first segment and the second segment, a third inner partial coupler between the second segment and the third segment, and a fourth inner partial coupler between the third segment and the fourth segment, and an outer ring surrounding the inner partial couplers.