Constrained Turbo Block Convolutional Codes for 100 G and Beyond Optical Transmissions

Abstract

Constrained turbo block convolutional (CTBC) codes are developed for 100G and beyond optical transmissions. The CTBC codes developed herein each fit within one optical transport network (OTN) frame. The CTBC codes involve a simple outer block code that is serially concatenated with a simple inner recursive convolutional code using a constrained interleaver that simultaneously delivers a high interleaver gain and a high minimum Hamming distance. Codes with 11.1 dB net coding gain (NCG) at 12.5% overhead (OH), 11.3 dB NCG at 15% OH, 11.6 dB NCG at 20% OH, and 11.9 dB NCG at 23.4% OH are reported. Compared with other codes that have been previously proposed for OTN applications, CTBC codes have much lower encoding/decoding complexity, improved NCG/OH tradeoffs, and avoid negative error floor effects.