Real-time transceiver implementation for SC-FDE acoustic modems

We have developed a real-time underwater acoustic modem with single-carrier frequency domain equalization (SC-FDE) transmission. Channel estimation operates in the time domain to improve accuracy, and equalization operates in the frequency domain to reduce complexity. The system is implemented on the floating-point OMAPL138 platform. Through optimization in the algorithm and program scheduling, the high data rate and real-time performance of the modem is guaranteed. We have tested the designed system in a lake experiment in June 2016. At a distance of 5 km, the modem achieved real-time raw data rates of 9600 bps with uncoded bit-error rates of 10 −3 in the complex environment.