Design and verification of SoC for OFDM-based visible light communication transceiver systems and integration with off-the-shelf analog front-end

Abstract

In this paper, a System-on-Chip (SoC) design for Orthogonally Frequency Division Multiplexing (OFDM)-based Visible Light Communication (VLC) transceiver is presented. The VLC transceiver system comprises the physical (PHY) layer and analog front-end (AFE). The OFDM modulation was implemented in the PHY layer. We design the SoC-based PHY layer using the “reuse methodology”. In this methodology, the Intellectual Property (IP) cores do not necessarily need to be created from scratch as it can be obtained from a 3rd party. Using this methodology, it can increase our productivity during the designing process. This methodology is suitable for developing an OFDM system, especially in VLC system, that requires high complexity blocks. When the IP cores are not available from the 3rd party, they can be designed from scratch. We design the IP cores with the AXI4 protocol standard which is widely used in SoC design. Later, the OFDM system IP cores are integrated by using the AXI4-Stream protocol. In addition, the dual-core ARM Cortex-A9 processor is integrated into the OFDM system IP cores using the AXI4-Lite protocol. The transmitter (TX) and receiver (RX) applications run on Linux OS (Xilinux) can access the OFDM system IP cores with the memory–mapped I/O method. To guarantee the successful design, we have tested our SoC design with the off-the-shelf AFE transceiver integration in a real setting. The analog part for this work was created by available commercially components. Three modulation types were selected for the field test, i.e., BPSK, QPSK, and QAM-16. The maximum data rates of VLC system also have been investigated in a real-time as a proof of concept of the proposed SoC architecture.