Research And Implement On Signal Processing In Testing Doppler Log's Velocity

Doppler log is a precise instrument, which is used to measure ship velocity and calculate its voyage on the theory of Doppler Effect of sound wave in water. It has been an important equipment of ship navigation system for many years. In this thesis, we researched on the signal processing in testing the velocity of Doppler log and its implementation.The main tasks of this thesis are:1. This thesis studied the measurement methods of frequency in signal processing used in testing Doppler log's velocity. Comparing several kinds of commonly useful methods' bias and mean square error and operation amount by the simulation of computer, it proved that the Zero-Crossing Method and the Complex-Correlation Method had more advantages on estimation.2. We implemented the methods by the hardware and the relevant software. We designed the algorithms for the two kinds of above-mentioned methods in the computer and the DSP. And also we designed the software for the data collecting.3. We carried out the simulated test.