Title :
A nonuniform sampled coherent pulsed Doppler ultrasonic velocimeter with increased velocity range
Author :
Nogueira, Gesse Eduardo Calvo ; Ferreira, Andre ; Vidal, Jose Tort
fDate :
3/1/1999 12:00:00 AM
Abstract :
Coherent pulsed Doppler ultrasonic velocimeters cannot measure large blood velocities in deep vessels. To overcome this limitation, a nonuniform sampling method is proposed. The method is based on adding a delayed sampling sequence interlaced to the conventional one. The time interval between two consecutive samples can be continuously adjusted to avoid undesirable sample volumes. Experimental results are shown, confirming theoretical expectations that the maximum measurable velocity and the maximum measurable velocity width are doubled.
Keywords :
Doppler measurement; biomedical ultrasonics; blood flow measurement; blood vessels; velocimeters; blood velocity measurement; blood vessel; coherent pulsed Doppler ultrasonic velocimeter; double pulse repetition frequency; medical diagnosis; nonuniform sampling; Added delay; Bandwidth; Blood; Diseases; Frequency measurement; Nonuniform sampling; Pulse measurements; Sampling methods; Ultrasonic variables measurement; Velocity measurement;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on