need of digital systems and sampling theorem and aliasing effect

1. SAMPLING
Presented by:
KAPIL GUPTA

2. WHY DIGITAL?
 Regeneration of Signal/ Rebirth of Signal
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3.  Error Detection and Correction
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4. Digital circuits are reliable and less costly.
Encryption and Privacy.
Data processing options

5. ANALOG TO DIGITAL CONVERTOR
Three steps are involved in A/D conversion
1. Sampling 2. Quantization 3. Encoding
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6. WHAT IS SAMPLING ?
 Sampling is the reduction of a continuous time signal to
a discrete time signal.
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7. SAMPLING PROCESS
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9. CAN g(t) RECONSTRUCTED ?
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10. SAMPLING THEOREM
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11. IDEAL RECONSTRUCTION
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12. ALIASING
1. The loss of the tail of G(f) beyond frequency .
2. The reappearance of this tail inverted or folded back onto the
spectrum.
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13. Tail inversion is known as Spectral folding or Aliasing.
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14. THE ANTI-ALIASING FILTER
Anti-aliasing filter applied before sampling.
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15. SPECTRUM WITH ANTI-ALIASING FILTER
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