Modified Phoenix cell for microstrip reflectarray antennas

This paper presents a new modification to the structure of a linear reflectarray cell, called Phoenix [1]. The idea of Phoenix is based on employing multi-resonators to improve the antenna bandwidth characteristics. Another interesting feature is the phase variation cycle which is characterized by a rebirth capability that was the reason behind the phoenix name. The new developed modifications resulted in reducing the cell size by 0.16λ₀. In addition to improving the linearity of the phase variation characteristics which in turn reduced the phase errors by 10° compared to Phoenix. Two reflectarray antennas (200×200mm²) were designed at 9.4 GHz in order to test the new modifications applied. The simulations and measurements indicated increased antenna directivity for the new modified Phoenix reflectarray antenna. Moreover, the measured gain of Phoenix and modified Phoenix at 9.4 GHz is 17.8 dB and 20.9 dB, respectively.