The Design Of Command Control System Of Underwater Acoustic Beacons

In order to manager and control the multi-function underwater acoustic beacons,a command control system designed in the thesis mainly completed the design of hardware circuit and the development of software program.This paper realized ranging a single beacon,achieving the depth and voltage,remote releasing,laid the foundation of future extensions.Firstly,the development and research status of underwater acoustic remote control technology at home and aboard reviewed.Designed the various components of the system based on working principle.Combined the sync and encoding signal as the control signal form considering the characteristics of underwater acoustic channel.Taken the protect time strategy in encoding signal for the multipath effect.Chosen the frequency-hopping signal as the sync signal and discussed the realization principle of FH signal.Modulated the encoding signal with 2FSK and demodulated with FFT frequency discrimination.Then,based on the OMAP-L138 minimum system board,completed the design of peripheral circuit,mainly discussed A/D signal acquisition circuit,precision clock circuit,sequential logic control circuit,SD card data storage circuit,network interface circuit,serial interface circuit,power supply circuit and some other circuits.Based on the DSP of OMAP-L138,the software program realized A/D signal acquisition,EDMA control program,modulation and transmission the control signal,detection and demodulation the answer signal,completed the data exchange between DSP and ARM to facilitate data storage with SD card.Finally,undertaken comprehensive test to the designed system.Firstly,complete the functional test of each modules and transmission in lab,verified the correctness of hardware circuit design and software programing of the system.Then,by the test in the anechoic tank,the system designed in this thesis proved to meet the functional requirements.Finally,processed and analyzed the outfield test data.