The “Context” Algorithms for Estimation of Maximum Frequency in the Nonstationary Transcranial Doppler Signal
نویسندگان
چکیده
This paper presents a new concept of algorithms for estimation of maximum frequency ( fmax) in the nonstationary Transcranial Doppler (TCD) signal. The improvement of estimator’s properties is achieved by exploiting the knowledge about dynamic properties of the blood flow. The raw estimates of fmax, calculated with a conventional algorithm for short segments of TCD signal, are smoothed and used as a “hint” for the secondary processing of the signal. This method assures less noisy fmax estimates, without the slopes’ flattening, typical for plain linear low-pass filtering of raw estimates.
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