Design And Implementation Of Signal Processing Platform For Underwater Frogmen Communication System

The development of marine resources is of great significance to the development of human beings.However,due to the complex marine environment,the development of marine resources has encountered great limitations.In order to fully and reasonably develop marine resources,protect the marine environment,and achieve sustainable development,the underwater work of professionally trained frogmen is essential.Underwater telephones are often used in underwater operations.Signal processing platforms are a key part of underwater telephones,and their design has an important impact on the performance of underwater communications.This dissertation designed a small,low power,stable and reliable signal processing platform for underwater frogman communication system.The single sideband modulation mode voice communication between the two underwater telephones and the multi-ary frequency shift keying mode communication between the underwater telephone and the ultrasonic communication module are realized.For the design needs,a complete requirements analysis,solution demonstration and component selection are carried out.The final signal processing platform adopts DSP+MCU architecture,and the DSP core of OMAP-L138 is the center of digital signal processing.The study designs audio power amplification,DDR2 storage,SD card storage,real-time clock,serial communication interface,voice signal encoding and decoding,voice signal recognition,voice signal synthesis,ultrasonic communication and other functions.The schematic and PCB design of the above functional modules were completed,the key signals of the DDR2 memory were simulated using Allegro PCB SI,simulate critical circuits with Pspice.The design of software mainly introduces the working mode of signal processing platform,voice menu control,DSP analysis of program loading mode,DSP program online upgrade mode,SD card driver,voice CODEC chip interface description as well as voice CODEC chip microphone input filter design and test.Finally,the correctness of the design is verified by the functional test of the signal processing board.The correctness and reliability of the design scheme were further confirmed by the lake test.At the end of the dissertation,the design is summarized,pointing out its shortcomings and making plans for the next working step according to the problems unsolved.