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Slide 2 Kalasalingam University, Digital Signal Processing and Applications, Nondestructive Evaluation using Barkhausen Noise V.K. Madan, PhD BTech (IITD), PhD (IITB), PDF (U. Sask., Canada) Fellow: IETE, IE (India); LM: INS, IPA, NTSI, ASI, ISTE Senior Professor Kalasalingam University Ex: Scientific Officer (H), Bhabha Atomic Research Centre, Mumbai Professor, Homi Bhabha National Institute, Mumbai Professor, BITS, Pilani Teacher, PhD(Tech) Electronics Engrg, U of Mumbai Research Board Member, Kalasalingam University Slide 3 2 KALASALINGAM UNIVERSITY Kalasalingam Academy of Research and Education (under section 3 of UGC act 1956) Accredited by NAAC with B grade with CGPA of 2.81 on 4 point scale Slide 4 To Be a Centre of Excellence of International Repute in Education and Research To Produce Technically Competent, Socially Committed Technocrats and Administrators Through Quality Education and Research MISSION VISION 3 Slide 5 Global Association s Carnegie Mellon University, USA University of Oklahoma, USA Ball State University, USA East Tennessee State University, USA Georgetown University, USA University of Applied Sciences, Western Switzerland Centro De Investigacion Y De Estudios Avanzados Del IPN, Mexico INM Leibniz-Institute for New Materials gGmbH, H-66123 Saarbrucken, Germany Centre for Combinatorics, Nankai University, China Hannam University, South Korea Soongsil University, South Korea Technical University of Kosice, The Slovak Republic MoU with International Universities 4 Slide 6 Science, Technology, Art, Religion, Music Earlier: One state scientist like Archimedes, Nobility, Professors, Common people Newton: Philosophy of Natural Science Philosophy: An obstinate attempt to think clearly Disciplines, specialization Multidisciplinary, synthesis, fusion, merging of tools Hermann Hesse: The Glass Bead Game (Das Glasperlenspiel) Inspiration from Leonardo da Vinci: There is no man from whom I cant learn something Moral: Keep mind open to all disciplines and try to integrate them with your expertise. Respect the great people but question their work. Slide 7 John Masefield (Poet Laureate) Adventure on, for, from the littlest clue Has come whatever worth man ever knew; The next to lighten all men may be you Slide 8 Digital Signal Processing (DSP) and Applications Slide 9 What is DSP Used For? And much more! Slide 10 What is DSP? Digital Signal Processing the processing or manipulation of signals using digital techniques ADCDAC Digital Signal Processor Analogue to Digital Converter Digital to Analogue Converter Input Signal Output Signal Slide 11 Transforms Transforms -- a mathematical conversion from one way of thinking to another to make a problem easier to solve. Example: Logarithmic transformation transform solution in transform way of thinking inverse transform solution in original way of thinking problem in original way of thinking Slide 12 DSP: Applied 2012 IEEE Intl. Conf Emerging Signal Processing Applications (ESPA), Las Vegas (emerging applications) 3D technology for gaming, telepresence Gesture recognition for games and natural user interfaces Digital photography 4G wireless Robotics Multimedia tablets SP in automobiles: speech interfaces, cameras Voice search SP with multicore processors IPTV Slide 13 Dogma of Circle DSP The Greek Philosopher Plato Claudius Ptolemy (all the phenomena in the sky are produced by uniform and circular motion) Eudoxus: superposition of rotating spheres. Aristotle used upto 54 spheres Claudius Ptolemy replaced spheres by circles Vasco da Gamma India Columbus America Magellan world Nicholas Copernicus Luther: fool Johannes Kepler Slide 14 Propagation of the Dogma of Circle Astronomy (disappeared) reappeared in Physics (e i t ) Electrical Engineering (e j t ) Phasor: first used by Lord Raleigh in sound Phasor: introduced in EE by Oliver Heaviside Popularized by Kennelly and Steinmetz in USA in early 1900s. Still very important. Sinusoids are bread and butter of EEE Slide 15 Circle: Astronomy to Power System, DSP, Communication Engineering Power System: Phasor Analysis DSP: unit circle in the complex plane Communication Engineering: modulator Modulator or mixer Slide 16 Faith vs Reason in Science Last 100 years Fourier transforms are being used. Only uses for which the transforms are good are developed. Selective development. However it generated lot of knowledge base. Arthur Koestler: The sleepwalkers (challenges the habitual idea of a progressive science) Fourier transforms: Dont converge at discontinuity (Gibbs). Information intensive points: discontinuities. requires infinite sinusoidal waves. Noncausal: O/p before I/p Negative frequency Slide 17 Faith vs Reason in Science (contd.) Fermat conjectured in 1640 that all the Fermat numbers (2 2 m + 1 ) are prime. In 1732 Euler pointed out that the Fermat number 4294967297 was not prime. ( 90 years ) (Fermat numbers are useful in DSP) Minsky and Papert published from MIT in 1969 a book Perceptron and wrote "...our intuitive judgment that the extension (to multilayer systems) is sterile. In simple language it means that multilayer perceptron cannot realize Exclusive-OR gate. The research in neural networks was halted for 10 years until it was proved that their judgement was wrong. ( 10 years ). Slide 18 Facts J. Finlaisons report to House of Commons, London 1829 (used digital filter) Many digital filters with excellent properties were existing in 19 th century. FFT algorithm existed (1805) before Fourier transform (1822). Rediscovered in 1965. Fourier transform remained questionable till a paper by Norbert Wiener from MIT in 1930. Spread spectrum communication invented by by Hollywood actress Lamarr and composer Antheil. Used by US Navy during Cuba blocade by President Kennedy Slide 19 Fourier Theory Fourier introduced the idea of representing an arbitrary periodic function as a trigonometric series, eminent mathematicians such as Lagrange resisted it. Till 1930 : Fourier theory was useful for analyzing periodic and aperiodic functions, but not for random functions. Norbert Wiener from MIT in 1930 applied Fourier theory for analyzing random functions. Presently it is known as Wiener- Khinchin theorem'' stating that the power spectrum is the Fourier transform of signals autocorrelation function. Slide 20 Fast FourierTransform (FFT) C.F. Gauss had written in 1805, 'Experience will teach the user that this method will greatly lessen the tedium of mechanical calculation.' this method is FFT. It was rediscovered by Cooley and Tukey in 1965. "The FFT rediscovery has been called the most important numerical algorithm of our lifetime (Strang, 1994)." (Kent & Read 2002, 61)numerical algorithm Slide 21 A Peep Beyond Fourier Transform Numerous orthogonal transforms exist other than Fourier transform. Fourier transform is, however, most popular and most widely used compared to any other transform. Walsh-Hadamard transform Number theoretic transform Hartley transform Householder transform and many more... Slide 22 Third Century Chinese Verse by Sun Tzu (useful in Computers) We have things of which we do not know the number, If we count them by three, the remainder is 2, If we count them by five, the remainder is 3, If we count them by seven, the remainder is 2, How many things are there?.. Moduli: 3, 5, 7 Remainders: 2, 3, 2 Answer: 23 Slide 23 Sanskrit, Vedic Arithematic (useful in computer Science) Multiply: 1 1 1 by 1 1 1 Answer: 1 2 3 2 1 Trick: ascending, descending, symmetry Square: (52) x (52) Answer: 2704 (mental time 5 seconds) Trick: any number 30 to 70 50/2 = 25+2 = 27 and 2x2 = 4 Slide 24 Evariste Galoiss work is useful in DSP Slide 25 Cochlea: A bank of filters Human ears do not hear wave-like oscillations, but constant tone Often it is easier to work in the frequency domain (for cochlear animation: http://www.rockefeller.edu/labheads/hudspeth/mov ie06_popup.html ) http://www.rockefeller.edu/labheads/hudspeth/mov ie06_popup.html Slide 26 Analog, Discrete-time, and Digital Signal y(t) = A sin (2 ft + ) Analog signal? Discrete time signal? Digital signal: t and y(t) are quantized Slide 27 Signal Classification Periodic and aperiodic Determinstic and random Energy and power Analog and digital Type I and Type II (new classification) Slide 28 New Classification of Digital Signals: Type I and Type II (Madan et al) Type I and Type II; based on fundamental problems of aliasing and quantization noise (q.n.). The classification has enhanced the scope of DSP in many disciplines: Type I: aliasing and q.n. are addressed along the abscissa and ordinate respectively Type II: aliasing and q.n. are addressed along the abscissa Slide 29 Type I and Type II Signals Type II: Nuclear spectra like gamma, x- ray spectra, population sciences etc. DSP methods widely used for Type I signals, are generally not used for Type II signals. DSP methods have demonstrated numerous advantages for processing Type II signals,. Presently not many Type II signals are processed employing DSP. Slide 30 DSP Applications Developed Nuclear Spectral Processing Power Transformers (Maximum Entropy Spectral Analysis) Population Sciences Electric Arcs Speech Processing Magnetic Barkhausen Noise Slide 31 Speech Processing Slide 32 Bill Gates and Speech Technology Bill Gates : Microsoft is pushing touchscreen and speech technology to replace keyboards Slide 33 Speech signal Hood and TF Analysis Slide 34 Speech Coding Prediction A(z)A(z) s(n)s(n) + d(n)d(n) se(n)se(n) d(n)d(n) A(z)A(z) + + se(n)se(n) sr(n)sr(n) Transmit error Slide 35 Gamma Radiation and its Uses Medical Uses Academic and Scientific Applications Industrial Uses Nuclear Power Plant Slide 36 A Gamma Ray Spectrum Slide 37 Fourier Transforms of the Spectra Slide 38 SAMPO has 25,000 lines of FORTRAN, 10,000 lines of C, and 12,000 lines of assembler (DSP based: