Design and Implementation of a Compact 4 × 4 Microstrip Patch Antenna Array with Circular Polarization for Nano Satellite Applications

This paper presents a very compact, broadband 44 microstrip patch antenna array with right-hand circular polarization, high gain, and an axial ratio (AR) less than 2 dB for data transmission from cubic nanosatellites in the X-band. The antenna is fabricated on a single-layer Rogers RO4003 substrate. Key features of the proposed cubic satellite antenna include small size, lightweight, high efficiency, high gain, and wide bandwidth. For small satellite antennas, it is particularly important that the axial ratio is less than 2 dB and the gain exceeds 12 dB. The antenna described in this paper meets all these criteria. Another attractive feature of this antenna is its single substrate design; however, it is worth noting that the sensitivity of the design can lead to discrepancies between simulated and measured results. To achieve a suitable axial ratio along with high gain, a two-stage sequential phase feeding technique, along with parasitic patches and rotation of array elements, is employed. The final design measures 7575 mm and operates within the frequency range of$9-11 \text{GHz}$. The measured and simulated impedance bandwidths are$\mathbf{1 4. 6}$percent and$\mathbf{1 4. 7}$percent, respectively, for frequencies from 9.5 to 11 GHz and 9.4 to 10.9 GHz. The measured peak gain is 13.4 dBi, while the simulated gain is 16.3 dBi. The measured axial ratio from 9 to 11 GHz is 20 percent, and the simulated axial ratio from 9.5 to 10.9 GHz is 13.7 percent. Considering its simple configuration, small size, appropriate operating frequency, high gain, and low AR, the proposed array is an excellent candidate for use in remote communication systems for cubic nanosatellites.