The present invention provides a method and apparatus for a monolithic device utilizing cascaded, switchable slow-wave CPW sections that are integrated along the length of a planar transmission line. The purpose of the switchable slow-wave CPW sections elements is to enable control of the propagation constant along the transmission line while maintaining a quasi-constant characteristic impedance. The device can be used to produce true time delay phase shifting components in which large amounts of time delay can be achieved without significant variation in the effective characteristic impedance of the transmission line, and thus also the input/output return loss of the component. Additionally, for a particular value of return loss, greater time delay per unit length can be achieved in comparison to tunable capacitance-only delay components.
Weller, Thomas and Lakshminarayanan, Balaji, "Microelectromechanical slow-wave phase shifter device and method" (2007). USF Patents. 635.
University of South Florida