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Wavelength Plan Proposal - Intermediate Report -. ver. 1.1. SMF cut-off problem. Report at March meeting. Conclusion in March meeting presentation.
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SMF cut-off problem Report at March meeting Conclusion in March meeting presentation By reviewing the proposals in IEEE meetings and systematically narrowing the 10GE-PON system configuration achieving coexistence with current systems, we found that - US : TDM-based overlay is preferable - DS : WDM-based overly using L-band is only one solution. Wavelength allocation Candidate for 10GE-PON : L-band WDM filter problem of US/DS separation GE-PON (US) GE-PON (DS) Video OTDR l 1.66 1.61 1.46 1.41 1.56 1.26 1.51 1.21 1.36 1.31 Additional filters may be required to 1G-ONU and V-ONU. Action Item • Wavelength Plan Proposal
Configuration of optical filters in ONUs (1) Several types of optical filter configuration in ONUs are considered for coexistence, and in general these are mainly categorized into the following two cases: (Case-1) combination of several WDM filters, as shown in 3av_0703_hajduczenia_2.pdf, (Case-2) combination of WDM filters and optical bandpass filters. (Case-1) (Case-2) SWPF1 SWPF2 SWPF LD LD LWPF BPF 1260~1360 1G/10G Up 1480~1500 1G Down 1550~1560 Video 1574~1580 10G Down PD PD 1625~1650 OTDR
SWPF-1 SWPF-1 Configuration of optical filters in ONUs (2) (Case-1) (Case-2) Receiver side Receiver side Pass band Pass band 10G-PON (DS) 10G-PON (DS) 1G&10G-PON (US) GE-PON (DS) 1G&10G-PON (US) GE-PON (DS) Video Video SWPF-1 BPF LWPF-1 1.26 1.26 1.36 1.36 l l 1.55 1.55 1.48 1.56 1.48 1.56 1.50 1.50 SWPF-1 SWPF-1 Transmitter side Transmitter side Pass band Pass band 10G-PON (DS) 10G-PON (DS) Video 1G&10G-PON (US) GE-PON (DS) 1G&10G-PON (US) GE-PON (DS) Video SWPF-1 1.26 1.26 1.36 1.36 l l 1.55 1.55 1.48 1.56 1.48 1.56 1.50 1.50 The cost of the ONU would be mainly dominated by the optical transceiver components, and therefore the insertion loss property should be the most important factor in designing the filter to alleviate the optical transceiver specifications. From this perspective, first, the feasibility of the case-2 filter was considered because the smaller number of filters is preferable in terms of the insertion loss.
BPF specification (1) In studying the feasibility of the case2-type ONU blocking filters, we assumed the following conditions: (a) No additional filter to already deployed 1G-ONU and V-ONU, (b) Insertion loss : < 1dB, (c) Isolation@1560nm : > 35 dB, (d) No restriction on the module type, (e) ONU embedded filter (preferable). Isolation: 35dB Signal band: Video 10G-PON (DS) l 1560 1550 What is required guard band? On the above conditions, system vendors investigated the required guard band for blocking video signal.
BPF specification (2) Shortest wavelength of 10G DS band and required guard band Study results on the required guard band (GB) are reported from system vendors; • 35dB-Isolation and 40nm-GB would be necessary for PLC-type module. • 15~20nm-GB would be feasible for BIDI-type module. (There is a report that 5nm-GB would be theoretically feasible.) • For BOSA-type module, the insertion loss would be less than 1dB when the signal wavelength is assigned between 1574 and 1580nm. • 20nm-GB is now available for TO-CAN module. It is considered that 16nm-GB, the shortest l of 1574nm, would be possible. Longest wavelength of 10G DS band The longest wavelength is referred to ITU-T recommendations such as G.982 and 983, in which the signal wavelength range shall be less than 1580nm. Isolation: 35dB Signal band : 6nm Video 10G-PON (DS) l 1550 1560 1574 1580 Guard band : 16nm
Summary Configuration of optical filters in ONUs : WDM filter + BPF 10G-PON (DS) 1G&10G-PON (US) GE-PON (DS) Video Bandpass filter for extracting only downstream signal l 1.55 1.48 1.56 1.26 1.50 1.36 WDM filter for splitting and combining up- and downstream signals Wavelength allocation and BPF specification The shortest wavelength is bound by the characteristics of the optical BFP. The longest wavelength is bound by conventional ITU-T recommendations such as G.982 and 983, in which the signal wavelength range shall be less than 1580nm. Isolation: 35dB Signal band: 6nm Video 10G-PON (DS) l 1560 1580 1550 1574 Guard band: 16nm