Noise in Ultrasonic Image Converters

Chapter 2 in Delta-sigma Data Converters Quantization Noise in A/d Converters

Ultrasonic image analysis and image-guided interventions.

The fields of medical image analysis and computer-aided interventions deal with reducing the large volume of digital images (X-ray, computed tomography, magnetic resonance imaging (MRI), positron emission tomography and ultrasound (US)) to more meaningful clinical information using software algorithms. US is a core imaging modality employed in these areas, both in its own right and used in conj...

Extended Noise-shaping in Cascaded N-tone Σ∆ Converters

An N-tone Σ∆ converter is obtained by introducing N zeros in the noise transfer function (NTF) while maintaining a flat signal transfer function (STF). N-tone Σ∆ converters are particularly well suited for multi-carrier systems. While oversampling is a widely used technique to improve the resolution of the converter, different methods will have to be explored for systems with low over-sampling....

A Pseudorandom Binary Noise Ultrasonic System

The random noise ultrasonic system represents the state-of-the-art in terms of sensitivity and resolution for ultrasonic NDE systems. The principle impediment to its use in the field is the lack of real-time inspection capability. If a pair of pseudorandom binary noise sources are substituted for the white noise source in the random noise system, a real-time capability is achieved. An instrumen...

Geological noise removal in geophysical magnetic survey to detect unexploded ordnance based on image filtering

This paper describes the application of three straightforward image-based filtering methods to remove the geological noise effect which masks unexploded ordnances (UXOs) magnetic signals in geophysical surveys. Three image filters comprising of mean, median and Wiener are used to enhance the location of probable UXOs when they are embedded in a dominant background geological noise. The study ar...