Time-variant acoustic propagation characterization in seaport deployments

This paper presents a methodology to characterize the time-variant underwater acoustic channel for the development of coherent communication systems. The channel impulse response is extracted during trials in the Halifax harbour. To account for time-variance a fast tracking equalizer enhanced with spread spectrum technology is described and its ability to extract the channel variations is evaluated. The end-to-end bit error rate is used as a figure-of-merit to quantize the equalizer performance. As will be shown, the equalizer is capable of compensating for the Doppler effect as well as rapid changes in the multipath profile.