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Investigated results on direct-fed circularly polarized (CP) microstrip antennas for "Direct Broadcast Satellite" (DBS) system at 12 GHz have been reported. A full-wave microwave circuit simulator based on the method of moments and capable of handling the microwave surface impedance was used in theoretical analysis of the antennas. Antennas were fabricated from both normal conductor (copper) and superconductor (YBCO) for comparison. The measured results on resonant frequency, return loss, gain, bandwidth and axial ratio have been presented along with some design data. The antennas showed good axial ratio and bandwidth. In the comparison of gain, superconducting antennas showed a remarkable improvement over their metal counterparts. The gain of a 4-element array fabricated on both-side superconducting film was found 3.6 dB higher than that of copper array. Therefore, this antenna configuration is expected to be used in DBS system.