5G LDPC Intel® FPGA IP User Guide

ID 683107
Date 4/01/2024
Public
Document Table of Contents

4.1. 5G LDPC Decoder

The 5G LDPC Decoder supports all modes specified in the 3GPP New Radio specification. The decoder can be either a single decoder or dual decoders.

Input packets arbitration for dual decoders:

  • If the incoming packet has small Z, the IP sends it to the second decoder, if it is available. If the second decoder is full and not available to process the small packet, the IP sends the small packet to the first decoder, if it is available. If none of the two decoders are available for the small packet, the IP back pressures to the upstream
  • If the incoming packet has large Z, the IP sends it to the first decoder, if it is available. If the first decoder is full and not available to process this packet, the IP back pressures to the upstream. Even if the upstream has the subsequent packet that has small Z and the second decoder is available to process it, the packet doesn't arrive at the IP until the first decoder becomes available to process the previous big packet

The order of output decoded packets is in the order that the IP receives the packets, although the IP processes the packets out of order.