introduction to digital signal processing · digital or analog? digital signal processing is easier...
TRANSCRIPT
《数字信号处理》:导论 �Digital Signal Processing: Introduction
Introduction to Digital Signal Processing
DSP MOOC Course
What is Signal?
Signals: functions conveying information about the behavior or attributes of somephenomenon.
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Signal Processing
Introduction to DSP DSP MOOC Course DSP: Introduction 2 / 14
Analog and Digital Signal
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Digital Signal Processing
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Digital or Analog?
Digital signal processing is• easier for storage• more reliable and flexible• stronger immunity to noise• …
than directly processing Analog signals.
But Digital is less accurate, harder to implement ultra-high frequencies, more powerconsumption ...
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Evolution of Mobile Phone
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Evolution of Memory Storage
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Evolution of TV
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Some Applications of DSPSignal spectral analysis:
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Some Applications of DSP
Noise removal for speech:
Music in Time-domain Freq.-domain
Org.
Noisy
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Some Applications of DSP
Amp. Resp.
before filtering
after filtering
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Some Applications of DSP
Music synthesis by Karplus-Strong:
HL(z)+x[n] y[n]
z−L
produces harmonics with fundamental freq. ω0 = 2π/(L+0.5)
[1] http://legacy.spa.aalto.fi/demos/tunable-disp/[2] http://theneuralbit.com/comfortably-numb-synth.html[3] http://www.music.mcgill.ca/ gary/courses/papers/Jaffe-Extensions-CMJ-1983.pdf
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Some Applications of DSPImage Restoration:
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What will be learnt from DSP?
• Bridge from A to D:• Sampling• Quantification
• DSP in Time-Domain:• Convolution / Correlation• Filters / Filter Design
• DSP in Frequency-Domain:• DTFT / DFT / FFT• ZT• Filter Design
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