Digital Signal Processing

1. Digital Signal Processing Prof. V. N. Bhonge Dept. of Electronics & Telecomm. Shri Sant Gajanan Maharaj College of Engg, Shegaon – 444203 vnbhonge@gmail.com

2. DIGITAL SIGNAL PROCESSING (6ET4 ) SSGMCE Shegaon UNIT-I : Discrete time signals and system: Classification of signals, singularity function, amplitude and phase spectra, simple manipulation, Classification of systems, representations of systems, analog to digital conversion of signal. (10) UNIT-II: Z- transform: mapping of s-plane to Z-plane, Region of Conversion and its properties, Properties of Z-transform, evaluation of inverse Z-transform using long division method, PFE method and residue method, difference equation and its relation with system function, impulse response and frequency response . (9) UNIT-III: Discrete and Fast Fourier Transform: Discrete convolution, Discrete Time Fourier Transforms (DTFT), Fast Fourier Transform (FFT), Computing an Inverse DFT by Doing a Direct DFT. Fast convolution, correlation. (9) Dept. of E & T Prof. V. N. Bhonge

3. SSGMCE Shegaon UNIT-IV: Finite Impulse Response (FIR) filters: Magnitude and Phase response of digital filter, Frequency Response of linear phase FIR filter, Design techniques for FIR filter: Fourier series method, windowing method using Rectangular window, Half band digital filter. Realization of basic structure FIR system: Direct form, Cascade, linear phase. (8) UNIT-V: Infinite Impulse Response (IIR) filters: IIR filter design by approximation of derivatives, impulse invariant method, Bilinear transformation method, Butterworth filter and Chebyshev filter. Realization of basic structure IIR system: Direct form I, Direct form II, Cascade and parallel. (8) UNIT-VI: Multirate Digital Signal Processing: Sampling, Sampling rate conversion, signal flow graph, filter structure, polyphase decomposition, digital filter design, multilevel filter bank. Overview and architecture of DSP processor TMS320C54XX. (8 ) Dept. of E & T Prof. V. N. Bhonge

4. SSGMCE Shegaon TEXT BOOKS : • S. Salivahanan, A. Vallavaraj, “Digital Signal Processing”, Tata McGraw-Hill Education, 2001. REFERENCE BOOKS : • Oppenheim & Schafer, “Discrete time Processing”, PHI. • Proakis & Manolakis D.G., “Digital Signal Processing”, PHI. • Mitra S.K., “Digital Signal Processing”, TMH. • Roman Kuc, “Digital Signal Processing”, MGH. • Ifeacher E.C., Jervis B. W., “Digital Signal Processing”, Addison Wesley. • P. P. Vaidyanathan, “DSP and Multirate Systems”, PHI. Dept. of E & T Prof. V. N. Bhonge

5. Introduction to DSP’s SSGMCE Shegaon • DSP’s process signals • Signal – a detectablephysical quantity or impulse (as a voltage, current, or magnetic field strength) by which messages or information can be transmitted (Webster Dictionary) Dept. of E & T Prof. V. N. Bhonge

6. Signal Characteristics: • Signals are Physical Quantities: • Signals are Measurable • Signals are Analog • Signals Contain Information. • Examples: • Temperature [oC] • Pressure [Newtons/m2] or [Pa] • Mass [kg] • Speed [m/s] • Acceleration [m/s2] • Torque [Newton*m] • Voltage [Volts] • Current [Amps] • Power [Watts] • In this class, analog signals are electrical. • Sensors: are devices that convert other physical quantities (temperature, pressure, etc.) to electrical signals. SSGMCE Shegaon Dept. of E & T Prof. V. N. Bhonge

7. SSGMCE Shegaon • DSP process digital signals: • Analog-to-Digital Converter (ADC) • Binary representation of the analog signal • Digital-to-Analog Converter (DAC) • Digital representation of the signal is converted to continuous analog signal. • Analog  Continuous Dept. of E & T Prof. V. N. Bhonge

8. ADC SSGMCE Shegaon a) Continuous Signal b) Amplitude Quantized Signal fs AnalogLow-passFilter Sampleand Hold x(t) xa(nT) Quantizer DSP x[n] c) Amplitude & Time Quantized – Digital Signal Prof. V. N. Bhonge Dept. of E & TC Dept. of E & T

9. DAC SSGMCE Shegaon a) Digital Output Signal b) Analog Signal c) Continuous Low-pass filtered Signal DSP Digital toAnalog Converter AnalogLow-passFilter y(t) y[n] ya(nT) Prof. V. N. Bhonge Dept. of E & TC

10. Extraction of Information Amplitude Phase Frequency Spectral Content Transform the Signal FDMA (Frequency Division Multiple Access) TDMA (Time Division Multiple Access) CDMA (Code Division Multiple Access) Compress Data ADPCM (Adaptive Differential Pulse Code Modulation) CELP (Code Excited Linear Prediction) MPEG (Moving Picture Experts Group) HDTV (High Definition TV) Generate Feedback Control Signal Robotics (ASIMOV) Vehicle Manufacturing Process Control Extraction of Signal in Noise Filtering Autocorrelation Convolution Store Signals in Digital Format for Analysis FFT … Why Processing Signals? SSGMCE Shegaon Prof. V. N. Bhonge Dept. of E & TC

11. Typical Architecture of a DSP System SSGMCE Shegaon Analog Signal Processing Analog SignalConditioning Sensor Digital Signal Processing Digital SignalConditioning ADC DSP DAC Prof. V. N. Bhonge Dept. of E & TC

12. Signal Processing • Humans are the most advanced signal processors • speech and pattern recognition, speech synthesis,… • We encounter many types of signals in various applications • Electrical signals: voltage, current, magnetic and electric fields,… • Mechanical signals: velocity, force, displacement,… • Acoustic signals: sound, vibration,… • Other signals: pressure, temperature,… • Most real-world signals are analog • They are continuous in time and amplitude • Convert to voltage or currents using sensors and transducers • Analog circuits process these signals using • Resistors, Capacitors, Inductors, Amplifiers,… • Analog signal processing examples • Audio processing in FM radios • Video processing in traditional TV sets SSGMCE Shegaon Dept. of E & T Prof. V. N. Bhonge

13. Limitations of Analog Signal Processing SSGMCE Shegaon • Accuracy limitations due to • Component tolerances • Undesired nonlinearities • Limited repeatability due to • Tolerances • Changes in environmental conditions • Temperature • Vibration • Sensitivity to electrical noise • Limited dynamic range for voltage and currents • Inflexibility to changes • Difficulty of implementing certain operations • Nonlinear operations • Time-varying operations • Difficulty of storing information Dept. of E & T Prof. V. N. Bhonge

14. Digital Signal Processing digital signal digital signal analog signal A/D DSP D/A analog signal SSGMCE Shegaon • Represent signals by a sequence of numbers • Sampling or analog-to-digital conversions • Perform processing on these numbers with a digital processor • Digital signal processing • Reconstruct analog signal from processed numbers • Reconstruction or • Analog input – analog output • Digital recording of music • Analog input – digital output • Touch tone phone dialing • Digital input – analog output • Text to speech • Digital input – digital output • Compression of a file on computer Dept. of E & T Prof. V. N. Bhonge

15. DSP is Everywhere SSGMCE Shegaon • Sound applications • Compression, special effects, synthesis, recognition, echo cancellation,… • Cell Phones, MP3 Players, Movies, Dictation, Text-to-speech,… • Communication • Modulation, coding, detection, equalization, echo cancellation,… • Cell Phones, dial-up modem, DSL modem, Satellite Receiver,… • Automotive • ABS, GPS, Active Noise Cancellation, Cruise Control, Parking,… • Medical • Magnetic Resonance, Tomography, Electrocardiogram,… • Military • Radar, Sonar, Space photographs, remote sensing,… • Image and Video Applications • DVD, JPEG, Movie special effects, video conferencing,… • Mechanical • Motor control, process control, oil and mineral prospecting,… Dept. of E & T Prof. V. N. Bhonge

16. Digital Telephone Communication System Example: SSGMCE Shegaon Prof. V. N. Bhonge Dept. of E & TC

17. SSGMCE Shegaon Thank You Dept. of E & T Prof. V. N. Bhonge