Abstract
The Kasai autocorrelation estimator is widely used in Doppler optical coherence tomography and ultrasound to determine blood velocities. However, as a non-parametric estimator, it may not be optimal. Assuming an additive white Gaussian noise (AWGN) model, we show that the Kasai estimator variance is far from the Cramer-Rao lower bound. Moreover, paradoxically, the Kasai estimator performance degrades as the acquisition rate is increased. By contrast, the additive white Gaussian noise maximum likelihood estimator (AWGN MLE) variance asymptotically approaches the Cramer-Rao lower bound, making it a better estimator at high acquisition rates. Nevertheless, the Kasai estimator outperforms the AWGN MLE under moderate levels of multiplicative decorrelation noise, and could therefore be considered more robust. These findings motivate further work in maximum likelihood estimators under conditions of both additive and multiplicative noise.
Original language | English (US) |
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Title of host publication | 2012 IEEE Biomedical Circuits and Systems Conference |
Subtitle of host publication | Intelligent Biomedical Electronics and Systems for Better Life and Better Environment, BioCAS 2012 - Conference Publications |
Pages | 264-267 |
Number of pages | 4 |
DOIs | |
State | Published - Dec 1 2012 |
Externally published | Yes |
Event | 2012 IEEE Biomedical Circuits and Systems Conference: Intelligent Biomedical Electronics and Systems for Better Life and Better Environment, BioCAS 2012 - Hsinchu, Taiwan, Province of China Duration: Nov 28 2012 → Nov 30 2012 |
Other
Other | 2012 IEEE Biomedical Circuits and Systems Conference: Intelligent Biomedical Electronics and Systems for Better Life and Better Environment, BioCAS 2012 |
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Country | Taiwan, Province of China |
City | Hsinchu |
Period | 11/28/12 → 11/30/12 |
Keywords
- Cramer-Rao bounds
- Doppler optical coherence tomography
- Doppler ultrasound
- frequency estimation
- maximum likelihood estimation
ASJC Scopus subject areas
- Hardware and Architecture
- Biomedical Engineering