DEVICE FOR INCREASING NOISE-IMMUNITY FOR ULTRASONIC CONTROL Russian patent published in 2009 - IPC G01N29/04 

FIELD: physics.

SUBSTANCE: device has four switching devices, bandpass and elimination filters, six peak detectors, signal delay device, two units for measuring ratio of signal levels, two threshold devices, device for combining and subtracting signals. In formation signals through the first two switching devices reach the inputs of the first two peak detectors, as well as through the amplifier and the third switching device to the outputs of the bandpass and elimination filters. The input of the bandpass filter is connected to the input of the signal delay device and to the input of the third peak detector, and the output of the elimination filter is connected to the input of the fourth peak detectors. Outputs of the third and fourth peak detectors are connected to inputs of the second unit for measuring ratio of signal levels. Also the output of the third peak detector is connected to the input of the first unit for measuring signal levels, the second input of which is connected to the output of the first peak detector. Outputs of both devices for measuring ratio of signal levels are connected inputs of the device for combing signals through the threshold devices. The output of device for combining signals is connected to the control input of the fourth switching device, the signal input of which is connected to the output of the signal delay device. The output of the fourth switching device is connected to the input of the first and second coherent or non-coherent accumulators, outputs of which are connected to inputs of the subtraction device. The output of the subtraction device is connected to the input of the sixth peak detector, and the output of the first accumulator is connected to the input of the fifth peak detector. Amplitude values of information signals which are processed and from which noise has been filtered off are tapped from outputs of these peak detectors.

EFFECT: increased noise immunity during ultrasonic control.

13 dwg