Patent ID: 8463361
Filing Date: 2013-06-11
Classification: A61B

Abstract:
1. A method for determining changes in cardiac chamber volume in a body using an ultrawideband (UWB) medical radar transceiver, the UWB medical radar transceiver including a transmitter and a receiver and a signal processor including software elements and a central processing unit, the method comprising: (a) transmitting from said transceiver a series of electromagnetic pulses into a body such that said electromagnetic impulses encounter a boundary between different biological regions in the body and small amounts of incident energy from said electromagnetic pulses encountering the boundary are reflected back towards said receiver as raw reflections; (b) capturing said raw reflections and pre-processing them using said receiver wherein said receiver captures a plurality of said raw reflections using a high speed sample and hold circuit where capture time for a sample of said raw reflections is set equal to a round trip time of flight from said transmitter to one or more depth ranges of interest and back to said receiver; (c) integrating said plurality of sampled reflections from said depth ranges of interest to form an integrated signal; (d) filtering said integrated signal to minimize irrelevant high frequency noise so as to avoid corruption of desired data related to tracking instantaneous cardiac chamber volume; (e) amplifying said integrated signal and passing said signal through a low-pass filter to prevent signal aliasing prior to digitization; (f) collecting and integrating a predetermined number of reflections for a first range of interest (g) changing said receiver sample timing and capturing reflections from a next range of interest (h) repeating (a) through (g) until reflections from an entire range of interest across the cardiac chamber are collected; (i) continually repeating (h) to deliver an updated instantaneous measure of cardiac volumetric changes.