under construction
Q: What is ECE 438 about?
A: Digital signals and systems.
Q: What is a digital signal?
A: A signal that can be represented by a sequence of 0's and 1's. The signal must be discrete time (D.T.): x[n], n e Z The signal values must come from a discrete and finite signal. e.g. x[n] e {0,1}
x[n] e {0,1,2,3,...,255} (grayscale values)
The Digital System
digital signal -> system -> digital signal
Three main types
- Software (MATLAB, C program)
- Firmware
- Hardware
Advantages of Digital Signals & Systems Digital Systems are:
- Precise
- Reproducible
- Easy to build
- Adaptable
- Easy to upgrade/fix
- Can be saved on a bistable storage device
x(t) CT World -------------------> x[n] DT World
The Continuous Time (C.T.) World
- Most natural signals live here
- Things are intuitive
- Easy Math
The Discrete Time (D.T.) World
- Digital lives here, along with computers, MATLAB, and digital circuits.