ITU 25G PON LDPC Encoder and Decoder

The common transmission convergence (ComTC) layer for Higher Speed Passive Optical Networks is defined as part of the FEC in the ITU-T G.9804.2 Recommendation.

The ITU 25G PON LDPC Encoder and Decoder support the default LDPC (17280, 14592) coding scheme, as well as the optional LDPC (17152, 14592) scheme. The IP cores are available for ASIC and FPGAs (AMD Xilinx, Intel, Microchip).

• Support for code rates 38/45 and 57/67
• Uncoded block size of 14592 bits
• Compliant with "Higher speed passive optical networks - Common transmission convergence layer specification, Recommended Standard, ITU-T G.9804.2, October 2021

• Key benefits of the decoder are:
  • Scalable solution allows for deployment on a wide range of target technologies
  • Low-power and low-complexity design
  • Layered LDPC decoder architecture for faster convergence behavior
  • Block-to-block on-the-fly configuration
  • Early stopping criterion for iterative LDPC decoder, saving a considerable amount of energy
  • Optional fixed number of iterations ensuring fixed latency for blocks with the same code rate and block length
  • Configurable amount of LDPC decoding iterations for trading-off throughput and error correction performance
  • Collection of statistic information (number of iterations, decoding success)
• Key benefits of the encoder are:
  • Coded throughput of 25.4 Gbit/s at a clock frequency of 300 MHz
  • Low-power and low-complexity design
  • Block-to-block on-the-fly configuration

• Passive Optical Networks (e.g. residential, business or mobile backhaul)

• VHDL source code or synthesized netlist
• HDL simulation models
• Bit-accurate Matlab, C or C++ simulation model
• Comprehensive documentation