Abstract
While the realization of 5G has already began, we are also experiencing a paradigm shift towards Open Radio Access Network (RAN) environments. This new paradigm promotes open and flexible RAN architectures, which can benefit by the physical layer processing being executed on open-source software and general purpose processors. However, meeting the real-time latency requirements for the computationally intensive process of Low Density Parity Check (LDPC) Decoding, as defined in the 3GPP 5G New Radio (NR), poses a challenge for such software based systems. Based on that, we report the design and implementation our novel FPGA LDPC offloading prototype which we integrate and evaluate with the OpenAirInterface (OAI) codebase, the fastest growing open-source project towards supporting 5G NR. For the first time, we present a detailed quantitative analysis of the capabilities of LDPC offloading into an FPGA in the context of a 3GPP compliant system, with up to 5 times faster execution times for the decoding. Our contribution includes the finding that offloading to specialized hardware does not necessarily improve processing latency in all LDPC configurations, due to overheads related to data transfers.