Design of a Ku-Band Single-layer Broadband Circularly Polarized Reflectarray Antenna

Design of a Ku-Band Single-layer Broadband Circularly Polarized Reflectarray Antenna

In this paper, a Ku-band broadband single-layer reflectarray antenna with Left-Hand Circularly Polarization (LHCP) is presented. Radiation elements of the reflectarray are gapped-ring that set on the surface antenna with a variable angle to form an arbitrary radiation pattern. First, a radiation element with 0.7𝜆×0.7 𝜆 dimensions at the central frequency (15 GHz) is designed and simulated using Floquet port in HFSS software. In the whole band, the co- and cross-polarization reflection coefficients are 0 dB and less than -15dB, respectively. Also, results of the phase of the reflected wave show that the designed unit cell with variable angles of the radiation element generates the very smooth linear phase curve with a gentle slope. Therefore, this unit cell is proper for broadband reflectarray antenna design. Second, the set of the gapped ring with variable angles constitute the reflectarray antenna with dimension 4.9 𝜆 ×4.9 𝜆. The array is simulated with HFSS software. Results show that the difference of between co- and the cross-polarization level is more than 13dB at whole Ku-band. However, the 3-dB axial-ratio (AR) and 1-dB gain bandwidths are 40% and 25%, respectively.

In this paper, a Ku-band broadband single-layer reflectarray antenna with Left-Hand Circularly Polarization (LHCP) is presented. Radiation elements of the reflectarray are gapped-ring that set on the surface antenna with a variable angle to form an arbitrary radiation pattern. First, a radiation element with 0.7𝜆×0.7 𝜆 dimensions at the central frequency (15 GHz) is designed and simulated using Floquet port in HFSS software. In the whole band, the co- and cross-polarization reflection coefficients are 0 dB and less than -15dB, respectively. Also, results of the phase of the reflected wave show that the designed unit cell with variable angles of the radiation element generates the very smooth linear phase curve with a gentle slope. Therefore, this unit cell is proper for broadband reflectarray antenna design. Second, the set of the gapped ring with variable angles constitute the reflectarray antenna with dimension 4.9 𝜆 ×4.9 𝜆. The array is simulated with HFSS software. Results show that the difference of between co- and the cross-polarization level is more than 13dB at whole Ku-band. However, the 3-dB axial-ratio (AR) and 1-dB gain bandwidths are 40% and 25%, respectively.