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This study presents a new S-band-receiving phased-array antenna with a phase-deviation-minimized calibration method for the ground station of a low Earth orbit (LEO) satellite. The proposed antenna consists of 16 subarrays, 16 beamforming receiving RF modules (BF-RFMs), a power/control board, and a 16-way feed network. The subarray was achieved by joining two 8 × 1 arrays with a two-way power combiner. The 16-element antenna subarrays showed a gain of 16.1 dBi and a reflection coefficient of less than −10 dB from 2.12 GHz to 2.45 GHz. The BF-RFM, which consists of three low-noise amplifiers (LNAs), a power combiner, a phase shifter, and a digital attenuator, was designed and fabricated. The BF-RFMs were provided by the power/control board and showed a gain of 30.8 ± 0.8 dB, an amplitude root-mean-square (RMS) error from 0.25 dB to 0.28 dB, and a phase RMS error from 1.8° to 2.5° over the Rx frequency range. The arrangement procedures of the 16 BF-RFMs are presented to increase beam pointing accuracy at the desired angle. A commercial 16-way feed network was employed to combine all the output ports of the 16 BF-RFMs. The assembled antenna, which has dimensions of 1.58 m × 1.58 m × 0.2 m, was measured by partial and full scans in the near-field scanning system. The back-projected algorithm was employed to calibrate the antenna’s gain patterns in the partial scan. The implemented phased-array antenna had a gain greater than 28.14 dBi, sidelobe levels less than −17.1 dB, and beam pointing errors less than 0.07° over the beam pointing angle of −20°~+20°. Based on the implemented antenna system, we conducted a field test using KOMPSAT-5, which is actually operating in South Korea, in order to verify the performance of the low Earth orbit (LEO) satellite ground station system.

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Automatic dependent surveillance-broadcast (ADS-B) is an advanced technology for air traffic monitoring. Using frequency of 1090 MHz, ADS-B transponder transmit aircraft identity, altitude, speed, position, and other information periodically to ground station. Nanosatellite Laboratory of Telkom University develops Tel-USat 2, a CubeSat with ADS-B signal receiver as the mission in purpose to expand the scope of its signal reception. This paper presents a rectangular truncated corner microstrip antenna for ADS-B receiver on a nanosatellite with center frequency of 1.090 MHz, Voltage Standing Wave Ratio (VSWR) = 1,15 with bandwidth of 11,5 MHz in the frequency range of 1.086 -1.097,5 MHz, unidirectional radiation pattern, circular polarization with axial ratio = 2,89 dB, antenna gain = 4,22 dBi and able to receive ADS-B signals from aircraft with furthest detected distances of 320,17 Km.