The Design of Variable Bandwidth Filter in Multibeam Bathymetric Systems and its Application on FPGA

In multibeam bathymetric systems, the presence of noise greatly reduces the reliability of phase difference estimation, and effective filtering is an urgent need. Aiming at the feature that the impact of noise varies over the measuring swath, the paper proposes a design of variable bandwidth filter. Compared with the fixed bandwidth filter commonly used, the variable bandwidth filter can increase the signal to noise ratio effectively with less computation and the structure is convenient for the real-time implementation on digital signal processor. It is proved through computer simulation and the implementation on FPGA is given to prove the realizability of the signal processing method of variable bandwidth filter.