Underwater acoustic communications: Design considerations at the physical layer based on field trials

An overview of the unique challenges in underwater acoustic (UWA) communication in ocean environment is presented. The UWA channel is compared with conventional RF channels. Several design considerations applicable to the physical layer design of a UWA communication system is described based on field measurements. The unique problems in synchronization under high Doppler are described highlighting the key differences in the way Doppler affects the RF and UWA channels. A novel timing synchronization mechanism has been introduced in this study which caters for both the sampling skew offset and the Doppler shift between the transmitter and the receiver.