Microfluidically Reconfigurable Reflection Phase Shifter

A microfluidic-based reconfiguration approach is presented for realizing a reflection phase shifter. The phase shifter consists of quadrature hybrid coupler with reflective microstrip line terminations. A selectively metallized plate (SMP) that can be repositioned inside a microfluidic channel is brought in close proximity (<;10 μm) of the reflective microstrip line terminations to vary their electrical lengths through capacitive RF short mechanism. The concept is demonstrated through a 9.5 GHz X-band phase-shifter design. Specifically, the design exhibits a footprint of 24 × 15 mm
²
, operates with <;0.95 dB insertion loss, and attains the 360° phase shift with a total of 9.5 mm SMP motion resulting in 1.95 s total actuation time with the selected external micropumps. These phase shifters may be suitable for applications that prioritize low-loss and high power handling capability over reconfiguration speed.