On the Design of 2D Flow Imaging Systems
To generate a 2D velocity image takes inherently longer time than to generate a 2D structural image. One way to describe the reason for this, is that we have to observe a scatterer for a periode of time to be able to determine its velocity, and the accuracy of the velocity estimate increases as the time we observe the scatterer increases. We can draw an analogy to how the motion of an aeroplane or a star,far away in the sky, is observed. They appear to stand still, except if you observe them over a periode of time so you can see that they have moved. The same is true if we want to determine a Doppler shift in frequency of an ultrasonic echo: The accuracy of the frequency estimate, Df, is inversely proportional to the time we observe the signal, T.
KeywordsDoppler Shift Present Instrument Color Flow Mapping High Pulse Repetition Frequency Transducer Motion
Unable to display preview. Download preview PDF.
- 1.Angelsen BAJ, Kristoffersen K, Torp H. 2 D-flow Imaging with an Annular Array Scanner. 2 nd Int. Congress on Cardiac Doppler, (Abstract)Kyoto 1986Google Scholar
- 2.Linker D.T., Skjerpe T, Samstad S, Rossvoll O, Chapman J.V., Kristoffersen K, Angelsen B.A.J. Color Flow Mapping with an Annular Array Transducer: An Approach Integrated with CW and Pulsed Doppler in Adult and Pediatric Patients. 2nd International Congress on Cardiac Doppler (Abstract), Kyoto 1986Google Scholar
- 3.Angelsen B.A.J., Torp H, Kristoffersen. Technical Principles and Approaches to Color Doppler Flow Imaging. 7th Symposium on Echocardiography (Abstract), Rotterdam 1987Google Scholar
- 4.Linker D.T., Rossvoll O, Chapman J.V., Angelsen B.A.J. Sensitivity and Speed of CFM verses CW Doppler in the Detection of VSD. 7th Symposium on Echocardiography (Abstract), Rotterdam 1987Google Scholar
- 5.Linker D, Angelsen B.A.J. Johansen H.C., Lønstad H., Torp H. Computer Analysis of 2D Tissue and Flow Images.(Abstract) Heart and Vessels Supplement 3: 1–52 1987Google Scholar
- 6.Angelsen B.A.J., Kristoffersen K, Torp H. Diagnostic Information in the Color Flow Images.(Abstract) Heart and vessels Supplement 3: 1–52 1987Google Scholar
- 7.Chapman J.V., Brun P., Meguira A, Torp H, Angelsen B.A.J. A new method of Indicating Disturbed Flow in a Color Flow Mapping System. (Abstract)Heart and Vessels Supplement3: 1–52 1987Google Scholar