US 12,149,346 B2
Frame coding and optical network unit (ONU) synchronization in passive optical networks (PONs)
Andy Shen, Morganville, NJ (US); Xiang Liu, Marlboro, NJ (US); Yuanqiu Luo, Cranbury, NJ (US); and Frank Effenberger, Frisco, TX (US)
Assigned to Huawei Technologies Co., Ltd., Shenzhen (CN)
Filed by HUAWEI TECHNOLOGIES CO., LTD., Shenzhen (CN)
Filed on Sep. 14, 2022, as Appl. No. 17/944,902.
Application 17/944,902 is a continuation of application No. PCT/US2020/044890, filed on Aug. 4, 2020.
Claims priority of provisional application 62/993,422, filed on Mar. 23, 2020.
Prior Publication US 2023/0019473 A1, Jan. 19, 2023
Int. Cl. H04L 1/00 (2006.01)
CPC H04L 1/0057 (2013.01) [H04L 1/0041 (2013.01); H04L 1/0052 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method implemented by an optical network unit (ONU) in a 50-gigabit-capable passive optical network (50G-PON), the method comprising:
receiving an encoded downstream (DS) physical layer (PHY) frame from an optical line terminal (OLT), the encoded DS PHY frame comprises a forward error correction (FEC) codeword, the FEC codeword comprises a superframe counter (SFC) field and a payload, and the SFC field and the payload are encoded with a same FEC;
decoding the FEC codeword using the FEC to obtain a decoded SFC field and the payload;
performing a first verification on the decoded SFC field while in a synchronization (sync) state of a synchronization state machine; and
staying in the sync state when the first verification is successful or exiting the sync state when the first verification is unsuccessful.