33 results about "Continuous wave doppler" patented technology

A handheld ultrasound instrument is disclosed having enhanced diagnostic modes including pulse / continuous wave Doppler, time-motion analysis, spectral analysis and tissue harmonic imaging. An external electrocardiograph (ECG) recording unit is also disclosed. The ECG unit is adaptable to be used with the handheld ultrasound instrument to provide for ECG monitoring while performing an ultrasound scan in B-mode, Doppler, color Doppler, M-mode, and CW / PW mode. The enhanced handheld ultrasound instrument further includes a security mechanism allowing any combination of the diagnostic modes to be enabled by the manufacturer, and later to enable or disable any one or group of the diagnostic modes. The invention also discloses a method for a manufacturer to maintain a database of handheld ultrasound instrument capabilities after the instruments enter the stream of commerce.

Continuous wave Doppler images in a data base comprising cardiac echo studies are processed to separate Doppler frames. The frames are pre-processed to extract envelope curves and their corner shape features. Shape patterns in Doppler images from echo studies of patients with known cardiac (valvular) diseases are employed to infer the similarity in valvular disease labels for purposes of automated clinical decision support. Specifically, similarity in appearance of Doppler images from the same disease class is modeled as a constrained non-rigid translation transform of velocity envelopes embedded in these images. Shape similarity between two Doppler images is then judged by recovering the alignment transform using a variant of dynamic shape warping. Since different diseases appear as characteristic shape patterns in Doppler images, measuring the similarity in the shape pattern conveyed within the velocity region of two Doppler images can infer the similarity in their diagnosis labels.

The present invention provides an object motion identification method based on a multi-channel continuous-wave Doppler radar. One antenna is employed to emit electromagnetic wave to irradiate the surface of a motion object to be measured, the reflected signals are received by 2-3 receiving antennas and are subjected to down conversion to a base band, the arcsine algorithm is employed to demodulate the phase information without the phase ambiguity limitation, the distance changing information between each receiving antenna and the motion object is obtained, the track formula is employed to obtain the object's motion track, and the mode identification is performed on the basis of the motion track. The object motion identification method based on the multi-channel continuous-wave Doppler radar can avoid the phase ambiguity problem of the arc tangent class function, is applied to the work condition with high the sampling rate and work condition with the low sampling rate and keeps the accuracy in the condition with the low sampling rate. The mode identification is realized on the basis of location and tracking of the object to be measured. The identification accuracy is high, the anti-interference capability is high, the configuration is simple, and the cost is low, the most of the demodulated motions are the linear relation with no need for the complex data processing process, and the hardware resource is saved.

A method of blood flow monitoring for a patient, the method comprising the steps of: a) receiving a first signal indicative of the real time cardiac output for the patient; b) processing the continuous wave Doppler signal to provide an estimate of blood flow velocity as a function of time; c) receiving a pressure measurement indicative of the blood flow resistance through the patient; and d) calculating an Inotropy measure indicative of the potential and kinetic energy of the cardiac output of the patient.

The invention relates to a liquid viscosity test method based on liquid drop mechanical vibration. The method concretely comprises the following steps that a hydrophobic substrate is placed on a ultrasonic probe of a Doppler ultrasonic instrument; liquid drops are generated on the hydrophobic substrate through a microinjector; the liquid drops are vibrated through a vibration triggering device with an automatic rebounding function; then, the vibration triggering device rebounds; the liquid drops generate free vibration; the free vibration of liquid drop surface capillary waves is converted into ultrasonic wave Doppler frequency shift signals by a non-focusing continuous wave Doppler method through the ultrasound probe, and the signals are amplified; a computer signal processing module collects and processes the Doppler frequency shift signals to obtain a liquid drop free vibration characteristic pattern; the free vibration characteristic pattern is subjected to fitting to obtain the decay rate of the liquid drop amplitude along with the time; further, the liquid viscosity is obtained through calculation. When the method is used for measuring the liquid drop viscosity, the responsespeed is high; the application range is wide; the reliability is high; the equipment is portable; the cost performance is high; the reagent consumption is little.

The invention discloses a fully coherent continuous wave Doppler radar and its distance measurement and speed measurement method. First, the difference frequency complex signal obtained by mixing the echo signal and the transmission signal is obtained, and according to the range frequency-Doppler frequency and the target distance ‑Modulation characteristics of velocity, using the two-dimensional joint detection method of distance dimension FFT + azimuth dimension MTD, using multiple coherent high repetition frequency modulation signals to independently obtain unambiguous radial velocity information, and then introduce the velocity into the Doppler The information is removed in the distance dimension and frequency domain information to eliminate the influence of distance-velocity coupling, so as to further obtain accurate distance information. The invention has the characteristics of coherent radar speed measurement and continuous wave radar distance measurement without distance blind zone, and meets the requirements of no distance blind zone, simultaneous distance measurement and speed measurement, real-time performance, miniaturization, and low power consumption.