The Design of Ultra‐Wideband 2‐Bit Switchable Circuit for Programmable Reflectarray

ABSTRACT A novel method for achieving the ultra‐wideband 2‐bit phase control by switchable circuit for programmable reflectarray is proposed. The microstrip line based active circuit is composed of three PIN diodes for dynamically selected four different reflective loads of open, short, capacitive and inductive characteristics respectively, and the theoretical calculation about the reflective phase of proposed circuit model can verify the basic method is correct. For considering the design of the ultra‐wideband reflectarray, the tightly coupling dipole (TCD) element is introduced for the ultra‐wideband electromagnetic wave receiving or radiating. And the co‐simulation of the period unit cell, launched by TCD structure and the measurement data from fabricated switchable circuit has shown the good results of 2‐bit phase control from 1.8 to 4.2 GHz with the relative bandwidth of 2.33:1.