Abstract: Performances of underwater acoustic communication (UAC) digital systems are strongly related to specific transmission properties of the underwater channel. Depending on the characteristics of the channel, an architecture and modulation techniques are usually implemented that are known as reliable solutions for data transmission in difficult radio channels. The OFDM technique seems to be the most promising nowadays. The parameters of the physical layer and data link layer of ISO/OSI model are adapted to the needs of underwater communications, so as to best protect the signal from distortions and interferences typical for the underwater environment. This paper compares the performance of UAC and wireless telecommunications systems working in channels of vary different transmission parameters. Based on these parameters, some physical and link layer configurations of OFDM data transmission systems are proposed for implementation in a laboratory model and testing at a lake.