| Marine safety problems have been an important part of ocean strategy. Ocean target detection is developing forehead constantly. Because acoustic vector sensor has directivity characteristics which have no relation with frequency, it has get wide attention in the area of target bearing estimation with low frequency. In array signal processing, beamforming technology is also concerned in the field of underwater acoustic.The thesis designs detection system based on the submerged array, which consists of vector hydrophones and an acoustic pressure array in engineering project. Focusing on the system software frame structures, vector hydrophone line spectrum signal and continuous spectrum signal automatic detection method, the thesis has completed the signal processing software system based on Linux system.The thesis discusses line spectrum signal and continuous spectrum signal automatic detection algorithm and designs the framework of signal processing system. The signal processing system’s task mainly includes data reception and storage, signal processing and information interaction with the main control unit. The network socket programming is used and the thesis uses UDP protocol to receive network data. The system gets the serial compass data by sending command to serial port RS485. The thesis chooses multi process to complete the data reception, storage and signal processing and the semaphore and shared memory to achieve the data sharing and synchronization between the parent process and the child process.The thesis completed the communication between the signal processing system and the main control unit through the serial RS232. Finally, the software implementation of the system was completed in the laboratory environment.At last, the field experiments are carried out to evaluate and verify the performance of the system and the signal processing algorithm. The results show that the performance of the system can meet the requirements of the project. The line spectrum signal automatic detection and continuous spectrum automatic detection method can accomplish the target detection and meet the project target. |
