Agenda
Review of the last lecture
Announced QUIZ
Formatting & Sampling
Quantization
Pulse Code Modulation
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Formatting And Sampling, Quantization-Digital Communications-Lecture Slides, Slides of Digital Communication Systems
This lecture was delivered by Mr. Sujay Rangarajan at Birla Institute of Technology and Science. Its part of lecture series on Digital Communications course. It includes: Formatting, Sampling, Quantization, Pulse, Code, Modulation, Spectral, Characteristics, Thermal, Noise, Autocorrelation, Function, Average, Power, Density, AWGN, Superimposed
Typology: Slides
2011/2012
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Agenda^ ^ Review of the last lecture^ ^ Announced QUIZ^ ^ Formatting & Sampling^ ^ Quantization^ ^ Pulse Code Modulation
White Noise
Adding AWGN noise to a signal ^ The effect on the detection process of a channelwith additive white Gaussian noise (AWGN) isthat the noise affects each transmitted symbolindependently ^ The term “additive” means that the noise issimply superimposed to the signal
Signal Transmission through LTISystems
Center for Advanced Studies inEngineering
Reading Assignment ^ Various Bandwidth Definitions ^ Page 47 to 50 ^ Quiz will be taken from this topic in thenext lecture
- QUIZ #
Formatting &Sampling
Ideal Sampling ( or Impulse Sampling) ^ Therefore, wehave: ^ Take Fourier Transform (frequency convolution)
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Ideal Sampling ( or Impulse Sampling) This means that the output is simply the replication of the originalsignal at discrete intervals, e.g
Center for Advanced Studies inEngineering
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Practical Sampling ^ In practice we cannot perform ideal sampling^
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It is not practically possible to create a train ofimpulses ^ Thus a non-ideal approach to sampling must be used ^ We can approximate a train of impulses using a train of very thin rectangularpulses:^ Note:^ ^ Fourier Transform of impulse train is another impulse train^ ^ Convolution with an impulse train is a shifting operation
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