摘要:
An ultrasonic imaging system for harmonic imaging includes a receiver which demodulates ultrasonic echo signals received by a transducer array and filters a band of fundamental frequencies from the echo signals by means of a notch filter. Images responsive to the filtered signals are presented on a display system.
摘要:
A phased array sector scanning ultrasonic system includes a separate beamformer channel for each respective element in an ultrasonic transducer array. Each beamformer channel has a three-stage complex FIR filter downstream of an analog-to-digital converter. Each filter circuit stage has a register pipeline, an in-phase FIR filter and a quadrature FIR filter. The first stage only has real samples, so there is a single pipeline. The other stages have complex inputs composed of in-phase (real) and quadrature (imaginary) samples, requiring a pipeline for each. Each register pipeline is made up of a multiplicity of registers connected in series. The number of registers in a given pipeline must equal the number of taps being used on the FIR filter immediately downstream of the register pipeline. The registers are clocked in synchronism and store successive echo data samples. Each register in the pipeline has an output connected to a respective tap of the corresponding FIR filter. In the second and third stages, the taps on the FIR filters receive data samples consisting of a real data sample from the I pipeline and/or an imaginary data sample from the Q pipeline. These complex data samples are multiplied by complex filter coefficients and the products are summed to form a respective filtered data sample output for each stage.
摘要:
A method of placing ECG electrodes in an environment where persons of limited training are available includes making a trial placement of the electrodes. Then, testing the electrodes and evaluating signals from the electrodes as a result of the testing. Verbal or visual feedback can be provided to the person placing the electrodes so that placed electrodes could be adjusted as needed.
摘要:
A personal emergency response system oriented to mobile individuals uses cell phones or other wireless devices as sources of an emergency indicating signal. A personal profile associated with that signal can be evaluated, along with location information to determine which emergency device(s) should be activated and which local messages should be produced to alert other individuals in the area as to the existence of an emergency.
摘要:
A method of placing ECG electrodes in an environment where persons of limited training are available includes making a trial placement of the electrodes. Then, the method includes testing the electrodes and evaluating signals from the electrodes as a result of the testing. Verbal or visual feedback can be provided to the person placing the electrodes so that placed electrodes could be adjusted as needed.
摘要:
A personal emergency response system oriented to mobile individuals uses cell phones or other wireless devices as sources of an emergency indicating signal. A personal profile associated with that signal can be evaluated, along with location information to determine which emergency device(s) should be activated and which local messages should be produced to alert other individuals in the area as to the existence of an emergency.
摘要:
An ultrasonic imaging system includes a transmitter using a memory to store waveshape and frequency data for energizing a transducer array. The data for multiple waveshapes is simultaneously read from memory and decoded by a demultiplexer so that data for a selected one of the waveshape can be sent to transducer array.
摘要:
A phased array sector scanning ultrasonic system includes a separate receive channel for each respective element in an ultrasonic transducer array. Each receive channel imparts a delay to the echo signal produced by each respective element. The delayed echo signals are summed to form a steered, dynamically focused and dynamically windowed receive beam even when the transmit beam does not emanate from the center of the array. The receiver has a beamformer including a multiplicity of beamformer channels. The beamformer dynamically increases delays to each channel without introducing unwanted discontinuities, by combining and synchronizing a FIFO and an interpolator. The interpolator uses "Wallace tree" adders to accumulate bit-shifted versions of the inputs. The number of additions is less than the number of bits which would be needed to represent equivalent coefficients. This reduces the hardware relative to a conventional implementation which incorporates multipliers with shifts and adds equaling the number of bits in the coefficients.