A green HPON–FSO communication architecture for energy-efficient high-speed optical networks

Abstract

The rapid growth of data traffic and digital services has increased the demand for high speed optical communication networks with reduced energy consumption. This study proposes an energy efficient Hybrid Passive Optical Network–Free Space Optics (HPON–FSO) communication architecture integrating hybrid Quadrature Amplitude Modulation–Phase Shift Keying (QAM–PSK) modulation, dynamic transmission power control, energy aware operation and optical burst switching. The proposed architecture combines a 20 km optical fiber link with a 1 km FSO link operating at 1,550 nm and a data rate of 10 Gbps. Its performance is evaluated in terms of power consumption, signal-to-noise ratio, energy efficiency, bit error rate, Q-factor and constellation characteristics. The proposed hybrid modulation reduces power consumption to 3.5 W compared with 5.2 W for QPSK, while increasing energy efficiency from 1.92 × 10 ⁹ to 2.86 × 10 ⁹  bits/J, corresponding to an improvement of approximately 49 %. The BER and Q-factor characteristics further demonstrate improved transmission reliability over the principal operating range. The architecture also considers the impact of atmospheric attenuation on the FSO link and highlights modulation flexibility under varying channel conditions. By reducing dependence on power-intensive components while maintaining acceptable signal quality, the proposed HPON–FSO architecture provides a flexible and sustainable approach, supporting reduced operational energy demand and reliable transmission for next-generation green optical communication networks.

OCIS Codes (060.0060) Fiber optics and optical communication.