Quadrature-to-directional format conversion of Doppler signals using digital methods
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Updated: Nov 10, 2026

Blood Flow Imaging with Ultrafast Doppler
Published on: October 14, 2020
1Division of Medical Physics, Faculty of Medicine, Leicester University, UK.
Abstract:
Four possible quadrature-to-directional format conversion methods using digital techniques are described. These are the phasing-filter technique, the extended Weaver receiver technique, the Hilbert transform in the frequency domain, and the complex FFT. All methods are implemented to give separated time domain outputs as well as frequency domain outputs. The theoretical descriptions are verified by practical implementations. Each of the methods has been implemented in real-time using a commercially available digital signal processing board.
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