Performance evaluation of a 100 Gbps dual-polarized QPSK-based intersatellite optical wireless communication (IsOWC) system under link impairments

Abstract This paper presents the design and comprehensive performance evaluation of a 100 Gbps dual-polarized quadrature phase shift keying (DP-QPSK)-based intersatellite optical wireless communication (IsOWC) system intended for high-capacity space-borne links. System performance is analyzed under varying link distances, transmitter laser power levels, receiver aperture diameters, transmitter and receiver optical efficiencies, and additional channel losses using key quality metrics such as bit error rate (BER), error vector magnitude (EVM), and constellation diagram analysis. Simulation results reveal that link distance and receiver aperture diameter exert a dominant influence on transmission reliability. For example, with a 15 cm receiver aperture, the log(BER) degrades from −4.21 at 10,000 km to −0.77 at 30,000 km, while EVM increases from 22.88 % to 51.82 %. When the aperture diameter is reduced to 10 cm, performance deterioration becomes more severe, with log(BER) reaching −2.76 at 10,000 km and −0.34 at 30,000 km, and EVM exceeding 60 %. In addition, higher transmitter laser power effectively mitigates pointing error impairments; at 30 dBm with a pointing error of 1 µrad, log(BER) improves to −2.60 compared with −1.42 at 26 dBm, accompanied by a reduction in EVM from 45.70 % to 32.60 %. Constellation observations further validate signal distortion trends, highlighting aperture optimization and power scaling as practical strategies for sustaining robust link quality in next-generation terabit intersatellite optical networks.