Rateless Code Profiles Design for Uplink C-RAN under Block Fading Channel

This paper considers a single user uplink transmission system based on rateless code in Cloud Radio Access Network (C-RAN) under block fading channel. The system consists of a single user, a cluster of remote radio heads (RRHs), and a building base-band unit (BBU) pool. The user encodes the messages with rateless code and sends them to RRHs. Each RRH quantizes the received signals and uploads them to the BBU pool through the high speed fronthaul link. BBU pool applies the belief propagation (BP) algorithm for joint decompression and decoding of the received signals. With only the knowledge of the statistics of the channel states, we design the universally good degree profile adopted at the user based on the extrinsic information transfer (EXIT) analysis 11)r the decoding process at the BBU. The simulation results show that, compared with the conventional BEC degree profile, the rateless code with the optimized degree profile achieves a better performance in the metric of average system throughput.