Design of a Low-Cost Single-Layer X/Ku Dual-Band Metal-Only Reflectarray Antenna

A low-cost single-layer dual-band metal-only reflectarray antenna (MORA) is designed, fabricated, and tested. It is capable of generating pencil beams with the same single linear polarization at X-and Ku-bands. The slot-type Phoenix elements are used to achieve the desired metal-only design, and by using a multiparameter sweeping strategy, they can provide sufficient phase shift coverage at the two design frequencies simultaneously. For the reflectarray system design, the dual-frequency phase-only synthesis method is adopted to further minimize phase errors at both frequencies. To experimentally validate the proposed design, an offset single-layer dual-band MORA prototype with a circular aperture of 380 mm in diameter is designed, fabricated, and tested. The measured gains are 29.1 dBi at 10 GHz with aperture efficiency of 51.3%, and 32.6 dBi at 15 GHz with aperture efficiency of 51.1%, respectively. The measured 1-dB gain bandwidth is 11.5% at the lower band and 17.5% at the upper band, respectively.