Design And Implementation Of MFSK Underwater Acoustic Communication Signal Processing Subsystem

In recent years, due to the needs of the military and marine development, there is growing emphasis on research of underwater communications systems. Sound waves as the only long-range transporting form in the water, so underwater acoustic communication has become a hot and difficult in the research of underwater communication. But water acoustic channel has a limited bandwidth, random time-varying, space-variable, frequency-dependent and signal's multi-path interference, these factors restrict the development of underwater acoustic communication technologies. The development of underwater acoustic communication technology is looking for efficient means to overcome the acoustic channel interference on the communication reliability.The task of this paper is to design and implement an underwater acoustic communication signal processing subsystem, including the system design and implementation of hardware and software platforms. The system is divided into transmitter and receiver by function, transmit-side include data reception and modulation, the receiver for signal reception and demodulation. System sender's working platform is based on TI's DSP processor design and implementation. In the system,program use MFSK modulation/demodulation methods and the RS coding techniques. The program is designed with VC6.0 software, System receiver adopt the Fast Fourier Transform for signal reception demodulation.System has been tested in the laboratory and Tianjin port, verified the reliability of system, but also found some shortcomings and deficiencies. At the last, discuss OFDM technology in the application of underwater acoustic digital communication system, sum up the basic principles and system solutions.