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Senior Capstone Project Integration of Matlab Tools for DSP Code Generation. ECE Department March 2nd, 2006. Team Members: Kwadwo Boateng and Charles Badu Advisors: Professor Thomas Stewart and Dr Inn Soo Ahn. Project Outline Project Summary Current Status Filter Implementation
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Senior Capstone Project Integration of Matlab Tools for DSP Code Generation ECE DepartmentMarch 2nd, 2006 Team Members: Kwadwo Boateng and Charles BaduAdvisors: Professor Thomas Stewart and Dr Inn Soo Ahn
Project Outline • Project Summary • Current Status • Filter Implementation • Modulation Schemes • Future Work • Questions
PROJECT SUMMARY • Integrate Matlab tools with code composer studio 3.1 software to generate C-code on DSP board (TMSC6713) • Integration process will involve Filter implementation and Modulation schemes • Filters and Modulation schemes (SPD) will be designed in Simulink and verified experimentally on an oscilloscope • Applications of SPD in industry will be examined • S-block functions not found in Simulink will be generated and called as subroutines. (MEX files) • SPD executed on DSP board via Mat-lab M file or Simulink block diagrams • Ultimate goal is to produce User Manual for DSP and Communication Theory Students.
SYSTEM BLOCK DIAGRAM Figure 1: High-level system block diagram
FIR Filter Design and Implementation NOTCH Filter Filter that passes most frequencies unaltered, but attenuates those in a narrow range to very low levels Given Equation: H(Z)=h0+h1z-1 + h2z-2 2 poles at origin which corresponds to Z2 2 zeros 45 degrees from the origin
Design of Filter given formulae for H(z) A Bandpass filter has transfer Function (Z-ejpi/4)(Z-e-jpi/4) H(z)= -------------------- Z2 Solve to get coefficients Num: [1 -1.41421 1] Den: [1 0 0] fa=fd*fs fd=Digital Frequency fa=Analog frequency fs=Sampling frequency Choosing fs= 8000Hz fd=1/8 ( Ranging between -.5 to .5) fa= 1000Hz
NOTCH FILTER DESIGN H(Z)=h0+hz1-1 + hz2-2
CommunicationSystems Figure 1-1: The Fundamental Model of Communication • Modulation Schemes • Amplitude Modulation (AM) • Frequency Shift Keying (FSK) • Double-Sideband Suppressed Carrier (DSB-SC) • Binary Phase-Shift Keying(BPSK) • Quadrature Amplitude Modulation(QAM)
Amplitude Modulation: the amplitude of a carrier signal is varied with respect to an input modulation signal to convey data. • Applications: commonly used at radio frequencies and was the first method used to broadcast commercial radio. • Modeled in project to transmit and receive speech signals. Amplitude Modulation (AM)
Envelope Detector Circuits AM Simulation Results AM Experimental Results
Frequency shift keying (FSK) is the most common form of digital modulation in the high-frequency radio spectrum • Used to send information between digital equipment like teleprinters and computers. • Data is transmitted by the frequency of a carrier in a binary manner to one or the other of two discrete frequencies. Frequency Shift Keying (FSK)
(FSK) Transmitter Signal Generation
FSK Receiver Test Square wave
Double-Sideband Suppressed Carrier Double-sideband suppressed-carrier transmission (DSB-SC): transmission in which: • (a) frequencies produced by amplitude modulation are symmetrically spaced above and below the carrier frequency • (b) the carrier level is reduced to the lowest practical level, ideally completely suppressed.
DSB-SC Transmitter DSB-SC Receiver
Binary Phase-Shift Keying • Phase-shift keying is a digital modulation scheme that conveys data by changing the phase of a reference signal (carrier wave) and BPSK is the simplest form of phase-shift keying. • Generated the same way as a DSB-SC, but m(t) is a unipolar data signal • Demodulated using a Costas loop
Modulation Schemes QUADRATURE AMPLITUDE MODULATION (QAM) Combination of : • Amplitude Modulation (AM) • Phase shift Keying (PSK) • Phase and Amplitude are Varied • Overcome constraints of complex AM or PM • Transmits more bits per second • Makes use of minimum bandwidth
GENERAL QAM TRANSMITTER S(t)=X(t)CosWct - Y(t)SinWct Wc=2pifc
QAM TRANSMITTER S(t)=X(t)CosWct - Y(t)SinWct Wc=2pifc
QAM RECEIVER Recovering Signals for Real X (t) & Quadrature Y (t)
EXPERIMENAL RESULTS FOR TRANSMITTER EFFECTS OF CAPACITOR COUPLING
Future Work • Implement Costas Phase-Locked Loop on DSP board • Work on Frequency Division Multiplexing (FDM) • Orthogonal Frequency Division Multiplexing (OFDM) • FM Stereo System