Versatile phasers constituted of coupling-free nonuniform stub-loaded transmission lines

A nonuniform stub-loaded and coupling-free broadband phaser is proposed as an alternative to conventional coupled-line sections based phasers for enhanced design flexibility, reduced complexity and lower cost in Radio Analog Signal Processing (R-ASP) systems. Nonuniform open- and short-terminated stub-loaded sections are employed to achieve specified highly flexible group delays with flat transmission magnitude responses. The phaser does not require multilayer or wire-bonding technologies since it consists of coupling-free transmission lines. The principle and synthesis procedure of the phaser are presented and two design examples with diverse specifications are presented with theory and full-wave simulation results. The phaser can be realized using microstrip technology and integrate with different lumped components and planar structures.