OFDM multi-sideband multi-subcarrier distribution technology based passive optical network system

Abstract

The invention belongs to the technical field of passive optical network (PON) system, in particular relates to an orthogonal frequency division multiplexing (OFDM) multi-sideband multi-subcarrier distribution technology based PON system. An OFDM signal is adopted in transmission of uplink and downlink of the system, and three-layer bandwidth distribution based on signal optical domain multiple sidebands, electric domain OFDM subcarrier and time slot can be realized. In the PON system, an optical line terminal firstly generates an optical source of N sidebands, data is modulated onto M specified downlink sidebands in OFDM form, the other N-M sidebands are distributed to a plurality of optical network units, so as to transmit OFDM signal of uplink data, and no additional local optical source is required. The system of the invention has high band utilization ratio and good signal distribution flexibility.

Description

technical field [0001] The invention belongs to the technical field of passive optical network systems, and in particular relates to a novel PON system based on orthogonal frequency division multiplexing multi-sideband multi-subcarrier allocation technology, namely OFDM-PON. technical background [0002] Passive Optical Network (PON, Passive Optical Network), the next-generation optical fiber access network, is currently the most concerned optical access network technology. It uses flexible wavelength division multiplexing, combined with time division multiplexing technology, to increase network capacity. And resource utilization reaches a very considerable level. In recent years, with the rapid development of broadband services and the continuous emergence of various new services, users' demand for network access to broadband has increased significantly. Broadband demand including voice, data, video and other potential services will exceed 100Mbit / s, traditional APON techn...

AI Technical Summary

Problems solved by technology

However, both schemes have certain disadvantages: the dual-wavelength scheme is not flexible enough, and the frequency band utilization rate is not high, and the remodulation scheme will limit the transmission distance of a single fiber due to the influence of Rayleigh scattering, and it is necessary to provide a continuous light for the uplink signal Modulation, so the downlink signal can generally only choose frequency keying modulation (FSK, Frequency-shift Keying), phase shift keying (PSK, phase shift keying), polarization keying modulation (PolSK, Polarization-shift Keying) and other modulation formats

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