Beam steering 60 GHz slot antenna array using liquid crystal phase shifter

A compact microstrip reflection-type phase shifter controlled by liquid crystal is used to realize a phased array of slot antennas. This array has a beam steering capability in one dimension for 60 GHz applications. In this array each phase shifter provides a differential phase shift of 188.5° at the operating frequency of 59.5 GHz. The final design comprises of a 4 × 1 slot array capable of scanning up to 70° in the E-plane as the bias voltage on the liquid crystal changes from zero to saturation voltage.

I. Introduction

The introduction of license free frequency band around 60 GHz has created new opportunities for short range, high data-rate applications. In Europe, this frequency band is 57–66 GHz, and in the US, is 57–64 GHz. To efficiently utilize this large bandwidth at low power consumption, it is desirable to have reconfigurable 60 GHz devices which are compact and cheap to manufacture.