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One of the biggest commercial applications of spintronics in computing to date has been the use of giant magnetoresistance (GMR), the material phenomenon that makes possible the huge storage capacity of today’s hard disk drives. In the awarding of the 2007 Nobel Prize in Physics, GMR was cited as the first big commercial application for nanotechnology. But extending the commercial application of spintronic-enabled systems beyond read heads for HDDs has proven to be a difficult task. One need only look at the seemingly endless travails of NVE Corporation, which in its financial results still shows it greatest revenue growth in contract research as opposed to product sales. While recent research from a team of researchers at Ohio State University and the University of Hamburg in Germany may not turn around the fortunes of spintronics in the short term, it does provide a way to better characterize the spin of electrons and thereby promises better ways of exploiting it for electronics applications. The researchers are reporting in Nature Nanotechnology that they have for the first time been able to create images of the spin direction of electrons.

There are severe flaws within the Harmonic-Balance and SPICE programs now widely used. Mentioned as far back as within an abstract of Session WSO at the 2008 IEEE International Microwave Symposium: "Even though nonlinear circuit-analysis software has been in use for many years, users still have difficulty obtaining valid results with existing methods.  Recognized problems include poor accuracy, convergence difficulties, long simulation times, and unstable results (i.e., results that vary greatly with minor changes in parameters).  These problems are encountered in both harmonic-balance and time-domain simulations."

National Instruments has released a vision module for the PXI platform that provides a high-performance parallel processing architecture for hardware-defined timing, control and image pre-processing. The NI 1483 Camera Link adapter module, in combination with an NI FlexRIO field-programmable gate array (FPGA) board, offers a solution for embedding vision and control algorithms directly on FPGAs which are used to process and analyse an image in real time with little to no CPU intervention. The FPGAs can be used to perform operations by pixel, line and region of interest. They can implement many image processing algorithms that are inherently parallel, including fast Fourier transforms (FFTs), thresholding and filtering.

Earlier in this series, we touched on one problem that can arise when sampling an analog signal, namely the problem of aliasing. There are three other issues with signal sampling to which we now turn our attention: digitization effects, finite register length effects, and oversampling. So far, weve assumed that all of the signals were measuring are continuous analog values; i.e., our measurements are completely accurate. Even in the cases in which we have noise, the underlying assumption is that the measurement itself, for example the noisy sensor output voltage, is known precisely.

We’re all familiar with the general idea of a filter: it removes something that we don’t want from something we do want. Coffee filters that pass the liquid coffee but retain the grounds or air filters that pass clean air but trap the dust and other pollutants are two common examples of mechanical filters in everyday life. That same concept can be applied to noisy electrical signals to pass through the “true” signal of interest while blocking the undesirable noise signal. Looking at Figure 2.5c below, imagine for a moment that the signal of interest is in the lower-frequency region and that the noise signal is in the higher-frequency region. Ideally, we’d like to be able to get rid of that high-frequency noise, leaving just the signal component that we want.

In earlier articles on intelligent sensor design, we saw how valuable they can be to both end users and those who manufacture and sell them. It’s now time to delve more deeply into what it takes to make intelligent sensors work.   The first step in that journey is to develop a solid, intuitive understanding of the principles of digital signal processing(DSP). Unlike many introductory DSP articles and texts, the focus here will be on presenting and using the important concepts rather than deriving them, for the simple reason that addressing the subject in depth is a book-sized, not a chapter-sized, project.

In high-end audio equipment, careful selection of resistors is one of the best ways to avoid or minimize noise and distortion in the signal path. This paper describes the noise generation in resistors manufactured using the various available resistor technologies and quantifies the noise insertion typical for each type.

TTE Systems' RapidiTTy IDE provides a self-contained environment for developers who wish to create "time-triggered" microcontroller software in order to improve overall system reliability. RapidiTTy (Figure 1, below) is intended to address deeply-embedded applications including control and monitoring operations in medical, defence, automotive and industrial sectors, as well as in white and brown goods.