Alexander J Holland

7383079, Jun 3, 2008

Apr 6, 2005

11/099849

Alexander Holland - West Linn OR, US

Welch Allyn, Inc. - Skaneateles Falls NY

A61B 5/0402

600509

Signal “peak” and “valley” removal properties of mathematical morphology operators are exploited in a method and apparatus for detecting, removing, or improving fidelity of pacemaker signal components of the Electrocardiogram (ECG) at sampling rates well below the pacemaker signal Nyquist rate. The method works for the wide variability in pacemaker signal amplitude, width, firing frequency, and other characteristics encountered in practice, and it works for malfunctioning pacemakers that may fire at any point relative to the QRS complex of the ECG signal. Filtering operations require minimal digital storage and are computationally inexpensive (no multiplications), mainly involving “maximum” and “minimum” type signal detections over a finite time history of the input signal. This implies that the method can be inexpensively implemented on small instruments in either hardware or software. The method may also be used to estimate the height and polarity of the pacemaker voltage spike, even though the base sampling period may be longer than the width of the spike.

7738949, Jun 15, 2010

Feb 26, 2008

12/037407

Alexander Holland - West Linn OR, US

Welch Allyn, Inc. - Skaneateles Falls NY

A61B 5/04

600512

The invention relates to a method for transforming physiological data from the time domain to the frequency domain. The method includes the steps of: providing a plurality of digital data in the time domain; providing a microcomputer programmed to run a recursive Fourier transform estimation algorithm; calculating, for each newly received digital data in the time domain, an integer index using modulo(N) arithmetic based on a time the each newly received data was received; selecting a frequency vector from a plurality of N frequency vectors using the integer index; and updating the plurality of frequency coefficients according to a recursive equation including the selected frequency vector as an input variable. The invention also relates to an apparatus that performs a recursive Fourier transform estimation algorithm to convert data in the time domain to data in the frequency domain.

20070078353, Apr 5, 2007

Oct 4, 2005

11/243175

Alexander Holland - West Linn OR, US

Welch Allyn, Inc. - Skaneateles Falls NY

A61B 5/04

600509000

According to one aspect of the invention, an improved ECG monitor includes a plurality of electrodes to be affixed to a patient's body to pick up ECG signals in an ECG signal band. The electrodes are electrically coupled to a plurality of input amplifiers. At least one analog to digital converter (“ADC”) is electrically coupled to the input amplifiers to digitize the ECG signals. A digital baseline wander filter has an internal finite impulse response (“FIR”) low pass filter characterized by a substantially trapezoidal impulse response. The baseline wander filter substantially removes a baseline wander signal component having a range of frequency components below the ECG signal band. The ECG waveform output signal is a baseline filtered ECG waveform representing the one or more of the ECG signals. The ECG waveform output signal from the improved ECG monitor is delayed less than 2 seconds from the ECG signals.

20070078354, Apr 5, 2007

Nov 10, 2005

11/270902

Alexander Holland - West Linn OR, US

Welch Allyn, Inc. - Skaneateles Falls NY

A61B 5/04

600509000

According to one aspect of the invention, an improved ECG monitor includes a plurality of electrodes to be affixed to a patient's body to pick up ECG signals in an ECG signal band. The electrodes are electrically coupled to a plurality of input amplifiers. At least one analog to digital converter (“ADC”) is electrically coupled to the input amplifiers to digitize the ECG signals. A digital baseline wander filter has an internal finite impulse response (“FIR”) low pass filter characterized by a substantially trapezoidal impulse response. The baseline wander filter substantially removes a baseline wander signal component having a range of frequency components below the ECG signal band. The ECG waveform output signal is a baseline filtered ECG waveform representing the one or more of the ECG signals. The ECG waveform output signal from the improved ECG monitor is delayed less than 2 seconds from the ECG signals.