Digital Signal
A discrete-time signal that has had analog values transformed into corresponding digital values is called a digital signal. An analog-to-digital converter is used in this conversion process to transform the sampled values into a sequence of digital numbers.
There are just two possible values for a digital signal: 0 and 1. As a result, another name for them is binary signals. where a high voltage level is denoted by a value of 1 and a low voltage level by a value of 0.
Type of Digital Signal
The two main categories of digital signals are as follows:
- Digital Unipolar Signal
- Digital Bipolar Signals
1. Digital Unipolar Signal
A unipolar digital signal is a kind of digital signal that uses the binary values 0 and 1 to produce either a positive or negative voltage level.
How it operates
- Every non-zero signal element in a unipolar signal has the same polarity.
- A binary 1 is represented by a positive voltage, and a binary 0 by a zero voltage.
- Unipolar signals are comparable to on-off keying, in which a binary one is represented by a voltage pulse and a binary zero by the absence of a pulse.
A bipolar digital signal is one that represents both positive and negative voltage levels using the binary states 0 and 1.
How it operates
- The amplitude of bipolar signals is symmetrical around zero.
- When sending bits, the line is either positive or negative, and it is kept at zero when not in use.
- To signal laziness or to divide bits, the line goes back to zero.
Advantages of Digital Signal
- Data can be protected by compressing and encrypting digital signals.
- It is simple to store digital signals on optical or magnetic media.
- Error rates can be reduced by using error detection and correction codes.
- Digital signals can be effectively compressed without suffering a large amount of information loss.
- Digital signals have reduced error rates and are more accurate.
Disadvantages of Digital Signal
- Compared to analog signal processing, digital signal processing consumes greater power.
- Quantization error is the discrepancy between the analog signal and the nearest accessible digital value.
- Because digital control systems require sophisticated hardware, software, and knowledge, they can be more costly.
- Compared to analog systems, digital systems are more complicated and call for more advanced hardware and software.
- A continuous output from digital sensors is not possible for every variation in the parameter being measured.
