LEC 1.pptx - Slides’ Acknowledgments • Digital Signal...

This preview shows page 1 out of 18 pages.

Unformatted text preview: Slides’ Acknowledgments • Digital Signal Processing by J. G. Proakis and D.G. Manolakis • Digital Signal Processing by S. Mitra • Prof. Oppenheim and Prof. Willsky from MIT Open Course Ware • Dr. Syed Talha Ahsan Engr.Syeda Aimen Naseem Course Text Book: Digital Signal Processing by J. G. Proakis and D. G. Manolakis 4th ed. 2007 Pearson Reference books: • Discrete Time Signal Processing by A. Oppenheim & R. Schafer 3rd (Indian) ed. 2013 Pearson • Digital Signal Processing; a Computer-based Approach by S. Mitra 4th ed. 2011 For practice of problem solving: Scahum’s Series’ Digital Signal Processing by M. H. Hayes Engr.Syeda Aimen Naseem LECTURE- 1 Engr.Syeda Aimen Naseem What is Digital Signal Processing? • Digital: Operating by the use of discrete signals to represent data in the form of numbers • Signals : A parameter (electrical quantity or effect) that can be varied in such a way as to convey information • Processing: 1) Analysis: understanding the information carried by the signal 2) Synthesis: Creating a signal to contain the given information Engr.Syeda Aimen Naseem Why Signal Processing required ? • When a signal is transmitted from one point to another there is every possibility of contamination/deformation of the signal by external noise. To retrieve the original signal at the receiver suitable filters are to be used i.e., the signal is processed to obtain the pure signal • Modify a signal such as noise reduction extract/enhance/rearrange the information. Engr.Syeda Aimen Naseem or data compression to Basic Elements of Signal Processing Digital input signal Digital output signal Engr.Syeda Aimen Naseem Advantages of Digital over Analog Signal Processing • Accuracy: The analog filters are vulnerable to temperature and external effects, but the digital filters have no such problems • Flexibility: Reconfiguration of analog filters is very complex whereas the digital filters can be reconfigured easily by changing the program coefficient • Complexity: Minimum complexity even complex mathematical operation can be performed easily using computers, which is not the case with analog processing. Engr.Syeda Aimen Naseem Limitation of DSP • Aliasing: Most signals are analog in nature, and have to be sampled Loss of information • Sampling Theorem: to avoid aliasing sampling rate must be at least twice the maximum frequency component of the signal. Engr.Syeda Aimen Naseem Engr.Syeda Aimen Naseem Limitation of DSP (cont.…) • Quantization • Complex error in real time system Engr.Syeda Aimen Naseem Applications Digital audio Cellular/mobile telephony Speech and channel coding Voice and data processing Power management Stereo and surround sound Audio equalization and mixing Electronic music Personal computer Automotive Digital Audio Sound cards , Data storage and retrieval Error correction/concealment Multimedia Modems Digital Radio Personal communication systems Engr.Syeda Aimen Naseem Medical electronics Critical/intensive care monitors Digital X-rays ECG analyzers Cardiac monitors Medical imaging Applications (contd.. MILITARY IMAGE MILITARY IMAGEPROCESSING PROCESSING INSTRUMENTATION &&CONTROL communication Pattern INSTRUMENTATIONSecure CONTROL Secure communication Patternrecognition recognition Spectrum Radar Robotic Spectrumanalysis analysis Radarprocessing processing Roboticvision vision Position control processing Image enhancement Positionand andrate rateSonar control Sonar processing Image enhancement Consumer applications Consumer applications Noise reduction guidance Satellite weather map Noise reduction Missile Missile guidance Satellite weather map digital television digital television SPEECH & AUDIO Data SPEECH & AUDIO animation Datacompression compression animation digital camera digital camera Speech recognition Speech recognition internet music, phones and video internet music, phones and video Speech synthesis Speech synthesis digital answer machines, fax and modems digital answer machines, fax and modems Text to speech TELECOMMUNICATION Text to speech TELECOMMUNICATION voice mail system voice mail digital audio Echo digital audio system Echocancellation cancellation interactive entertainment systems interactive entertainment systems Adaptive Adaptiveequalization equalization Video Biomedical Videoconferencing conferencing Biomedical data Patient datacommunication communication Patientmonitoring monitoring Scanners Scanners ECG ECG(Electrocardiograph) (Electrocardiograph) X-ray X-raystorage/enhancement storage/enhancement Engr.Syeda Aimen Naseem Types of Signals Continuous time and continuous valued signal (Analog Signal) Continuous time and discrete valued signal Discrete time and continuous valued signal (Analog Signal) Engr.Syeda Aimen Naseem Discrete time and discrete valued signal (After encoding Digital Signal) Classification of Signals • Multichannel and multidimensional: A signal is described by a function of one or more independent variable called multidimensional signal and signals are generated by multiple sources or multiple sensors are called multichannel signals Engr.Syeda Aimen Naseem Example s1 ( t ) s ( t ) 2 . S ( t ) . . MULTICHANNEL SIGNALS s ( t ) n y 1 I(x1,y 1) I r ( x, y , t ) I ( x , y , t ) I g ( x , y , t ) I ( x, y , t ) b x 1 Engr.Syeda Aimen Naseem MULTIDIMENSIONAL SIGNAL Classification of Signals (contd…) • Deterministic Signal: Any signal can be described by an explicit mathematical expression, a table of data, or a well-defined rule to emphasize the fact that all past, present, and future values of the signal are known precisely e.g. Sinusoidal signal • Random Signal: Signals that either cannot be described to any reasonable degree of accuracy by explicit mathematical formulas signals evolve in time in an unpredictable manner e.g. seismic signals, speech signals, etc. Engr.Syeda Aimen Naseem Open-Ended Activity-1 Engr.Syeda Aimen Naseem Solution of Open-Ended Activity-1 (Available in faculty shared folder) Engr.Syeda Aimen Naseem ...
View Full Document

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern