Lect1a_ basics of DSP.pptx
- 1. MODULE IV Digital signal processor: Digital signal processor and its design issues, evolving architecture of DSP, next generation DSP. Customizable processors: Customizable processors and processor customization, A benefit analysis of processor customization, use of microprocessor cores in SOC design, benefits of microprocessor extensibility.
- 3. What is Digital Signal Processing? Digital Signal Processing deals with algorithms for handling large chunk of data. A Digital Signal Processor is required to do the following Digital Signal Processing tasks in real time • Signal Modeling Difference Equation Convolution Transfer Function Frequency Response • Signal Processing Data Manipulation Algorithms Filtering Estimation
- 4. The basic Signal Processing Platform
- 5. Cont.. Application of mathematical operations to digitally represented signals Signals represented digitally as sequences of samples Digital signals obtained from physical signals via transducers (e.g., microphones) and analog-to- digital converters (ADC) Digital signals converted back to physical signals via digital-to-analog converters (DAC) Digital Signal Processor (DSP): electronic system that processes digital signals
- 6. D-A and A-D Conversion Process
- 7. The performance of the signal processing system depends to the large extent on the ADC. The ADC is specified by the number of bits which defines the resolution. The conversion time decides the sampling time. The errors in the ADC are due to the finite number of bits and finite conversion time. Some times the noise may be introduced by the switching circuits. Similarly the DAC is represented by the number of bits and the settling time at the output. A DSP tasks requires Repetitive numeric computations Attention to numeric fidelity High memory bandwidth, mostly via array accesses Real-time processing And the DSP Design should minimize Cost Power Memory use Development time
- 8. FIR filtering both by a General Purpose Processor as well as DSP
- 9. FIR Filter The output of the filter is a linear combination of the present and past values of the input. It has several advantages such as: Linear Phase Stability Improved Computational Time
- 10. FIR filter on (simple) General Purpose Processor loop: lw x0, (r0) lw y0, (r1) mul a, x0,y0 add b,a,b inc r0 inc r1 dec ctr tst ctr jnz loop sw b,(r2) inc r2
- 11. DSP TMS32010 It has got the following features • 16-bit fixed-point • Harvard architecture separate instruction and data memories • Accumulator • Specialized instruction set Load and Accumulate • 390 ns Multiple-Accumulate(MAC) Here X4, H4, ... are direct (absolute) memory addresses: LT X4 ;Load T with x(n-4) MPY H4 ;P = H4*X4 ;Acc = Acc + P LTD X3 ;Load T with x(n-3); x(n-4) = x(n-3); MPY H3 ; P = H3*X3 ; Acc = Acc + P LTD X2 MPY H2