Implementation of two polarization DQPSK WDM Is-OWC system with different precoding schemes for long-reach GEO inter Satellite link

The advantages of optical wireless communication in space are its fast speed, large capacity, lack of Electro-Magnetic Interference (EMI), high level of security, and broad bandwidth. OWC offers an advantage over microwave communication because the relay function in laser-based communication reduces system time. To achieve the long distances required for Geostationary Earth Orbit (GEO) communication, this paper designs and implements an 8-channel, Dual Polarization Differential Quadratic Phase Shift Keying (DP-DQPSK) Wavelength Division Multiplexing (WDM) system for inter-satellite optical wireless communication (Is-OWC). The system was built to accommodate 240 Gbps overall, and 30 Gbps in each channel, and the investigated transmission lengths were between (10,000 km to 48,000 km). Additionally, two precoding schemes were included in the investigation of the proposed system. To evaluate the system's performance, Quality Factor (QF), Log of Bit Error Rate (BER), and receiver sensitivity metrics will be examined to evaluate the performance of the proposed system. Such findings show that the proposed system, when utilizing a DPSK precoder, may accomplish reliable transmission across 40,000 km. In addition, the Duobinary precoder may be used for transmissions of up to 20,000 kilometers with higher performance when compared to the DPSK scheme. Furthermore, Duobinary improves the average QF by (7) dB and (0.92) dB, and receiver sensitivity by (-7.93) dB and (-3.28) dB at distances of 10,000 km and 20,000 km, respectively. In the future, numerous division multiplexing techniques may be utilized to boost the effect of the transferred data rate to fulfill modern satellite applications.