The document summarizes key points from Lecture 03 on analog-to-digital conversion for the course ICT3105: Digital Signal Processing. It discusses the three steps of A/D conversion: sampling, quantization, and coding. It then focuses on sampling of analog signals, explaining the sampling theorem which states that the sampling rate must be at least twice the highest frequency of the sampled signal to avoid aliasing. Examples are provided to illustrate frequencies above the Nyquist rate and the importance of the sampling rate being greater than twice the maximum frequency.

1. Associate Professor
Dept. of Electrical and Electronic Engineering
University of Dhaka
Dr. Mohammad Junaebur Rashid (JR)
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ICT3105: Digital Signal Processing (3.0 Cr)
Course Teacher
Bangladesh University of Professionals
Department of Information & Communication Technology

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Lecture 03
Analog-to-digital Conversion
ICT3105: DSP
• Conceptually, we view A/D conversion in three step process:
- Sampling
- Quantization and
- Coding

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Lecture 03
Analog-to-digital Conversion
ICT3105: DSP

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Lecture 03
Sampling of Analog Signals
ICT3105: DSP

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Lecture 03
Sampling of Analog Signals
ICT3105: DSP

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Lecture 03
Sampling of Analog Signals
ICT3105: DSP

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Lecture 03
Sampling of Analog Signals
ICT3105: DSP

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Lecture 03
Sampling of Analog Signals
ICT3105: DSP

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Lecture 03 ICT3105: DSP
To see what happens to frequencies above Fs/2, let us consider the following example
Sampling of Analog Signals

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Lecture 03 ICT3105: DSP
Sampling of Analog Signals
F2= 1/8=0.125 HzF1= 7/8=0.875 Hz
Fs = 1 Hz
So, it should be Fs > 2Fmax
Sampling Rate

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Lecture 03 ICT3105: DSP
Assignment
Sampling of Analog Signals

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Lecture 03 ICT3105: DSP
Sampling of Analog Signals
t=n/sample rate

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Lecture 03
Sampling Theorem
ICT3105: DSP

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Lecture 03
Sampling Theorem
ICT3105: DSP
Assignment: Example 1.4.3 and 1.4.4