Signal Processing Software Design Of Underwater Buoy Range Finder

The precise positioning of information acquisition element is the important guarantee for acoustic tomography, which is a key technology used in ocean spatial information collection and analysis. The dissertation is committed to the signal processing algorithm design and engineering software implementation of underwater buoy range finder depending on the underwater acoustic buoy element position calibration system which is based on the deep ocean acoustic tomography system.In algorithm design part, the signal detection system on the basis of adaptive notch filter is designed according to common narrowband signal, and the amplitude judgment is used to estimate the transponder response signal delay; To reduce the influence of background noise spikes and channel crosstalk, the variance of instantaneous frequency detector is employed,which can reduce the false alarm probability; To weaken the impact of pulse splitting influence leaded by the acoustic channel multi-path features, optimized detection logic is put forward, which improves the system detection performance. The broadband signal, which has excellent properties in the field of communication,is studied in this paper at the same time,a ranging measurements algorithm based on direct sequence spread spectrum and frequency hopping hybrid system is designed, the replica correlation is used to detect response signal and estimate time-delay. After analysis the performance diversity between narrowband and broadband system, the narrow-band signal processing form is chosen, collaborative the subsequent processing such as direct sound selection, to complete the algorithm design of range finder software platform.In engineering software implementation, the algorithm transplantation and peripherals developing based on TMS320C5509A DSP are completed. The general signal processing software structure is constructed according to the platform needs,and the core module functions of underwater buoy range finder signal processing software are realized,including the estimation and compensation of DC(direct-current) partial quantity in the response signal preprocessing procedure; the realization of multichannel parallel filter, the design of adaptive threshold for background noise, meanwhile the VIFD in the core detection and delay estimation procedure; the selection of effective pulse, as well as organize and store data in the subsequent processing. At the same time,the development of various peripherals is completed,based on the external equipment involved in the signal detection and delay estimation procedure, including the configuration for McBSPl in order to realize the A/D data acquisition and D/A signal emission of the platform, the realization of communication between DSP and console platform using the SPI mode of McBSP2 interface to transmit the instruction and original data, the configuration for DMA controller to enable the McBSP1 acquisition and launch signal independently, the development of I2C communication module to realize the communication between underwater buoy range finder DSP and microcontroller platform, and the rational allocation of general timer to both design the platform work timing and send signal at regular time.Finally, the function test, as well as the experiment condition of test in laboratory and on the lake,is summarized. Meanwhile the accuracy of ranging measurement is analyzed and demonstrated. The signal processing software of underwater buoy range finder designed in this dissertation is verified feasibility and effectiveness through the integrated test on the range finder system in laboratory and Thousand Island Lake experiment station.