Outline

  1. Sample Theory
  2. Filter

Recap:

Given data (say a music file), how to send the data via wireless signal?

  • E.g., Carrie the data using amplitude of a series of signal with frequency fc, then this data is sent at frequency fc with AM mudolation.

The at receiver, how to recover received signal - sampling

Sample is not same as Quantization

Example of quantization

​ Analog: phonograph record

​ Digital: MP3

Material: Nyquist’s Sampling Theorem

Filter

Material

Why we need filter(s)?
  • Demodulation example

Practice

A quick tutorial for FFT HERE

  • Let’s walk through with an example of 10 data points to make sense the “x-axis” of time/frequency domain.
  • Understand the Real and Img part out of fft.

FFT Documentation