Abstract: A method and apparatus that separates an interference signal from a sampled input signal is provided. The method and apparatus approximates the frequency, phase and amplitude of the interference signal through an optional reverse direction learning process and then separates that portion of the interference signal overlapped or combined with a sample of the input signal. The signals can be separated by generating a second signal of suitable approximation in frequency, amplitude and phase with the interference signal and then subtracting a sample of that signal from the sampled input signal. The second signal frequency and amplitude/phase may be derived through an iterative process that measures the amplitude of the interference signal and the phase angle between the second signal and an output signal and then adjusts the frequency and amplitude of the second signal based, in part, on these measurements until the second signal substantially matches the interference signal.
Type:
Grant
Filed:
November 12, 1999
Date of Patent:
February 26, 2002
Assignee:
GE Medical Systems Information Technologies, Inc.
Abstract: A defibrillator includes circuitry configured to produce a defibrillatory shock and an audio/video output unit having a database of video image information stored in a memory, a video display, and a video formulation unit coupled to the memory and configured to retrieve video information from the database of video image information and present corresponding information to the video display for display. The video information may include still images, animated images, motion images or a combination of textual information and at least one of still images, animated images and motion images. The audio/video output unit may be configured to receive inputs relating to user inputs, patient signals and device inputs, and to provide video instructions, and optionally audio or textual instructions, relating to operation of the defibrillator based on the current operational state of the defibrillator.
Abstract: An implantable medical device determines activity levels over a set of time periods, preferably on the order of seconds, minutes and hours and a display is enabled for days or weeks at recorded activity levels over a range of dates. This enables physician review of patient functional status. Additional physiologic data can be recorded along with the activity data, and this too may be reported out from the implanted device to a medical communications system for alarm purposes, titrating drugs or other monitoring tasks.
Abstract: An ambulatory recorder which features a method of configuring the size of data subject to loss in volatile memory. The recorder of the present invention determines how many processor sampling cycles it will take to fill the memory buffer. As discussed above this will vary a great deal and will directly depend upon the programmed parameters, e.g. number of channels to be sampled and the various sampling frequencies. The device then determines the amount of time this number of processor sampling cycles will take. If this amount of time is greater than a pre-selected amount of time, then the number of sampling cycles is reduced to be less than the pre-selected amount of time. The recorder uses these calculations to thereby schedule the transfer of data from the volatile memory to the non volatile memory. Through such an operation the data in the memory buffer subject to loss is limited to only a pre determined amount of time, i.e.
Abstract: This invention incorporates the discovery of new principles which utilizes magnetic fluxes generated by time varying square wave currents of precise repetition, width, shape and magnitude to cause them to move through multi-turns of conductive material generally in the form of a coil, in order to stimulate the cardiovascular system in humans or animals by directing the fields externally through the chest wall or the skull in order to correct arrhythmias and/or heart blocks. The new method of cardiovascular stimulation evolved from experimental observations of cardiac muscle cells which when separated, oscillate at different frequencies and propagate at different rates at specific sites in and around the heart and a cell oscillating at a higher frequency when touching a cell oscillating at a lower frequency causes the lower oscillating one to speed up and synchronize at the higher rate.
Type:
Grant
Filed:
September 11, 1985
Date of Patent:
February 9, 1988
Inventors:
Elizabeth A. Rauscher, William L. Van Bise