Design of a new self-adaptive dynamic filter in ultrasound imaging system

A new self-adaptive dynamic filter in ultrasound imaging system was proposed to match the center frequency of the dynamic filter and the real echo in real time. The fast Fourier transform (FFT) processor was used to analyze each small section of the echoes and the factors of the filters in the self-adaptive mechanism were decided by the frequency characteristic of the real echoes. The realization of the system was based on the field programmable gate array (FPGA). The timing simulation was analyzed and carried on by Modelsim which was dealing with sinusoidal signals doped with white noise. The simulation results showed that the self-adaptive dynamic could reduce the noise effectively as this method could match the center frequency of the near field and far field real echoes precisely. The new self-adaptive dynamic filter is fast enough for processing high-speed and real-time signals, providing one basis for designing the filters in ultrasonography.