OFDM for Underwater Acoustic Communications

Chapter 5Receiver Overview and Preprocessing

Chapters 5 to 17 contain the major body of this book–OFDM receiver design for underwater acoustic communications. One prominent feature of receiver algorithm design in underwater communications is that the receiving algorithms are heavily tailored to the characteristics of underwater acoustic channels, computational capability of system hardware, and desired system performance. Given large dynamics of an underwater acoustic environment and high cost of the system hardware, the primary goal of the receiving algorithm design is to achieve efficient and reliable communications with low computational cost, whereas a tradeoff always exists between system performance and algorithm complexity. To suit the necessity of various communication applications, both low-complexity and high-complexity receiving algorithms have their own merits. Meanwhile, reducing computational complexity while maintaining reliable communication performance becomes a major theme of advanced receiver design.

Compared to terrestrial radio communications, one unique feature of underwater acoustic communications is that communication channels in different applications could exhibit drastically different characteristics, and hence a universal receiver design might not exist. As a result, different communication applications have to be examined individually. Several typical communication scenarios will be considered in the following chapters of this book: (i) shallow water ...