Line coding is the process of converting digital data to digital signals for transmission. There are several types of line coding including unipolar, polar, bipolar, and multilevel coding. Common line coding schemes include non-return-to-zero (NRZ), return-to-zero (RZ), Manchester, and alternate mark inversion (AMI), with each scheme varying in how bits are represented as signal levels and transitions.

1. Line Coding

2. Line coding:
 Line coding is the process of converting digital
data to digital signals.
 Line coding converts a sequence of bits to a digital
signal.

3. Types of line coding:
Unipolar
Polar
Bipolar
Multilevel
Multitransition
Line Coding

4. Unipolar NRZ scheme

5. Polar NRZ-L and NRZ-I schemes

6. Polar RZ scheme

7. Polar biphase:
Manchester and differential Manchester schemes

8. Bipolar schemes: AMI and pseudoternary

9. Multilevel: 2B1Q scheme
Next bits Next level Next level
00 +1 -1
01 +3 -3
10 -1 +1
11 -3 +3
Previous level: Previous level:
Positive Negative

10. Multitransition: MLT-3 scheme