Zynq FPGA-based Transmitter for Underwater Acoustic Modem

In the recent era, underwater acoustic (UWA) communication technology has played a vital role in the UWA-wireless sensor network (UWA-WSN), widely used in the marine industry. Establishing stable and efficient underwater communication links is very challenging. There is a need for more reliable and affordable underwater communication modems that can both transmit and receive signals. This work aims to design and implement a transmitter for an underwater modem that uses amplitude shift keying (ASK) and is implemented on a field-programmable gate array (FPGA) evaluation board. Design is modeled using the hardware description language (HDL) module. This design has significant advantages like simplicity and resistance to interference. This work uses Xilinx Vivado Design Suite 19.2 software along with the System Generator Simulator and XST Synthesizer. The core of this work is a sine/cosine lookup table (LUT) which generates the signal of a desired frequency. This is a very efficient and reliable communication system because its carrier amplitude changes at every change in message signal. This work describes the simulation, synthesis procedure, and hardware implementation of an ASK system. The FPGA is programmed with a compact and optimal code, thereby reducing hardware resource requirements and lowering the production cost of the custom prototype. The signature waveform obtained as the output of the transmitter is observed on an oscilloscope and shown to match the theoretical one.