US 11,791,860 B2
Ultra compact and wide band folded Marchand Balun for millimeter-wave and beyond wireless communication
Min-Yu Huang, Richmond (CA); and Srinaga Nikhil Nallandhigal, Richmond (CA)
Assigned to SWIFTLINK TECHNOLOGIES INC., Richmond, CA (US)
Filed by SWIFTLINK TECHNOLOGIES INC., Richmond (CA)
Filed on Jan. 19, 2022, as Appl. No. 17/578,824.
Prior Publication US 2023/0231594 A1, Jul. 20, 2023
Int. Cl. H04B 1/40 (2015.01); H01P 5/10 (2006.01)
CPC H04B 1/40 (2013.01) [H01P 5/10 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A Marchand Balun, comprising:
a first port, a second port, and a third port;
a first transmission line being folded into a first and a second intermediate transmission lines, the first intermediate transmission line disposed on a first signal plane and the second intermediate transmission line disposed on a second signal plane, wherein a first end of the first intermediate transmission line is coupled to the first port, a first end of the second intermediate transmission line is open circuit, and a second end of the first intermediate transmission line is coupled to a second end of the second intermediate transmission line through inter-plane vias;
a second transmission line disposed on the first signal plane and is adjacent to the first intermediate transmission line, wherein an electromagnetic field generated by the first intermediate transmission line induces a signal in the second transmission line, wherein the second transmission line has one end coupled to the second port and an opposite end coupled to a reference plane; and
a third transmission line disposed on the second signal plane and is adjacent to the second intermediate transmission line, wherein an electromagnetic field generated by the second intermediate transmission line induces a signal in the third transmission line, wherein the third transmission line has one end coupled to the third port and an opposite end coupled to the reference plane.