09-04-2013, 03:43 PM
Data and Signals
Data and Signals.ppt (Size: 1.53 MB / Downloads: 56)
ANALOG AND DIGITAL
Data can be analog or digital. The term analog data refers to information that is continuous; digital data refers to information that has discrete states. Analog data take on continuous values. Digital data take on discrete values.
PERIODIC ANALOG SIGNALS
Periodic analog signals can be classified as simple or composite. A simple periodic analog signal, a sine wave, cannot be decomposed into simpler signals. A composite
periodic analog signal is composed of multiple sine waves.
DIGITAL SIGNALS
In addition to being represented by an analog signal, information can also be represented by a digital signal. For example, a 1 can be encoded as a positive voltage and a 0 as zero voltage. A digital signal can have more than two levels. In this case, we can send more than 1 bit for each level.