A Configurable OFDM Baseband Processor for RF-UOWC System-on-Chip

Dual-hop radio-frequency underwater optical wireless communication (RF-UOWC) systems enable underwater communication as well as above-water communication. RF technology is used for communication above the water surface, and optical communication is used underwater. In this work, we present an OFDM baseband processor on a programmable system-on-chip (SoC) FPGA. Our register transfer level (RTL) design of the OFDM is configurable, so it can be implemented for RF as well as UOWC. We have tested our design in real-time data transmission with both RF and underwater channels. The OFDM processor for RF communication is tested on ADRV9361-Z7035 FPGAs. With a channel bandwidth of 3.2 MHz, the achievable real-time data rate is 5.4 Mbps. The OFDM processor for UOWC is tested on RFSoC 4x2 FPGAs. With a channel bandwidth of 32 MHz, the achievable real-time data rate is 54 Mbps.