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Abstract

Operation of the √f centroid detector with various doppler systems is discussed, and its design, implementation, and performance are described. It is determined that the detector can be employed in directional detection schemes to measure spectral moments and centroids with correct polarity and with no degradation in accuracy. Narrow- and wideband deterministic signal detection of both stationary and FM information is investigated, and it is found that the centroid detector can also serve as an FM demodulator with high AM rejection.

A versatile √f detector was realized in discrete form and evaluated with deterministic and random signals, and its measured variance agreed closely with the theoretical values. The validity and application of the noise-reduction method was verified on deterministic and random doppler signals. Applications of the detector and the noise-reduction method to blood-flow and velocity measurements are demonstrated.

Keywords

Blood flow blood velocity demodulator doppler frequency modulation noise reduction power-spectrum centroid spectral moments ultrasonic

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The Power-Spectrum Centroid Detector: System Considerations,Implementation,and Performance

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