60 GHz 0-360˚ Passive Analog Delay Line in Liquid Crystal Technology based on a Novel Conductor-backed Fully-enclosed Coplanar Waveguide

Liquid Crystal-Filled 60 GHz Coaxially Structured Phase Shifter Design and Simulation with Enhanced Figure of Merit by Novel Permittivity-Dependent Impedance Matching

“…Excitingly, the idealized 100% mmW-PoVR in the tunable dielectrics of the coaxial structure implies a maximumly achievable transfer rate of a wave-guiding (transmitting) device structure that fully transfers the tuning capability of tunable dielectrics (i.e., LCs in this work) to the differential phase shift of the phase shifter device. As such, the unique advantage of the coaxial topology in the mmW-PoVR may tip the balance and enable it to compete with (or even outperform) established planar solutions in LC-based phase shifters (inverted microstrip [29] and coplanar-adapted structures [24,[32][33][34]). To answer this interesting question, the results of the performance evaluation and comparison are presented in Sections 3.3 and 3.4 based on the standalone device evaluations without the external bias tees.…”

“…New methods and structures should be in place to increase their acceptance in wider scenarios targeting wider stakeholders. Pondering about the year just past, we proposed a novel, partially shielded coplanar waveguide with metasurfaces for LC phase shifters beyond 67 GHz [32], 79 GHz meandering enclosed coplanar variable delay lines in LCs encapsulated within independent and shared cavities [33], and a 60 GHz 0-360 • passive analog delay line in LC technology based on a novel conductor-backed fully enclosed coplanar waveguide [34]. These structures are compact and planar (semi-planar) in nature, meaning that the core line is semi-open or partially open and, hence, is vulnerable to electromagnetic interference (crosstalk) [35], higher-order modes [24], noises, and related unstable problems [36] that can compromise the device's performance and reliability, in particular at higher-frequency mmW regimes.…”