Low-Cost Single-Substrate Reconfigurable Reflectarray Antenna Using RF SPDT Switches

This article proposes a low-cost single-substrate reconfigurable reflectarray antenna. A novel single-substrate reconfigurable unit cell is designed at first, utilizing only one radio frequency (RF) single-pole double-throw (SPDT) switch as a 1-bit phase shifter. Then, a square reconfigurable array composed of 256 unit cells is implemented, and each RF SPDT switch can be controlled through a control board, enabling two-dimensional beam scanning within the range of $\theta=-60^{\circ}$ to 60°. Simulation results indicate that low cross-polarization radiation and large beam-scanning range are realized simultaneously within the operating frequency band. Moreover, the proposed antenna achieves a bandwidth of $6.64 \%$, a peak gain of $17.6 \mathrm{d B i}$ and an aperture efficiency of $\mathrm{1 2 . 6 5 \%}$. With the simple array structure, high antenna gain and large beam-scanning range, this design could be applied in various wireless systems.