Enhancing Ultra-Dense Connectivity in IMDD Pons With P2MP Flexible Optical Transceivers for Concurrent Upstream and Direct Inter-ONU Communication
Keywords:
Passive Optical Network (PON), Inter-ONU Communication, P2MP TransceiverAbstract
Background: The imminent arrival of 6G networks necessitates a fundamental redesign of optical access networks to support unprecedented connection density, ultra-low latency, and extreme bandwidth. Conventional Passive Optical Networks (PONs), while successful for fiber-to-the-home, face significant architectural limitations in meeting these demands. Enabling direct, low-latency communication between Optical Network Units (ONUs) is a critical step, but existing methods often introduce complexity and cost. This article investigates a novel approach using Point-to-Multi-Point (P2MP) flexible optical transceivers within an Intensity Modulation and Direct Detection (IMDD) PON to address this challenge.
Methods: We propose and model a PON architecture where ONUs are equipped with advanced P2MP transceivers. This setup facilitates not only traditional upstream communication to the Optical Line Terminal (OLT) but also direct, concurrent inter-ONU data exchange. The operational principles are based on dynamic subcarrier allocation and sophisticated digital signal processing (DSP) for interference management. We developed a comprehensive simulation framework to evaluate the system's performance under ultra-dense traffic scenarios, analyzing key metrics including Bit Error Rate (BER), network throughput, latency, and, most critically, the maximum number of simultaneous connections the network can provision.
Results: The simulation results demonstrate that the proposed architecture successfully supports simultaneous upstream and high-speed inter-ONU traffic with negligible performance degradation. Compared to traditional PONs, our system exhibits a significant enhancement in connection provisioning capability, effectively handling a much denser user environment. For peer-to-peer traffic, the direct ONU-to-ONU path yields a substantial reduction in latency by eliminating the round-trip delay to the OLT.
Conclusion: The integration of P2MP flexible optical transceivers provides a powerful and efficient solution for enhancing the capacity and flexibility of IMDD PONs. This architecture is a promising candidate for future-proof optical access networks, capable of supporting the demanding connectivity requirements of 6G and beyond.
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Copyright (c) 2025 Dr. Kenji Tanaka, Prof. Eleanor Vance
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